Editor’s note: Are you too high right now? Go here to calm yourself or a friend.
One of the eternal questions in cannabis culture has finally been answered by science: After consuming marijuana, how long will you stay high?
In a 2021 study published in Neuroscience & Biobehavioral Reviews, researchers led by Danielle McCartney of the University of Sydney identified a “window of impairment” that lasts anywhere from three to ten hours, depending on the THC dose, the mode of ingestion, and the consumer’s previous cannabis experience.
After taking 20mg of THC, most consumers shed the high within four to five hours.
Those are a lot of factors, but the TL;DR is: generally, four hours.
The intoxicating high from a lighter inhaled dose will generally last for three hours, while a deep dabbing session or heavy edible may keep on hitting for six to ten hours.
Gathering data from 80 studies
McCartney and her colleagues undertook a comprehensive analysis of 80 scientific studies on cannabis dosage and intoxication.
Because the focus of their study was on the effect of cannabis intoxication on driving skill and awareness, much of the work skewed toward answering those questions.
The researchers found that cannabis consumers recovered most of their driving-related skills within five hours of inhaling 20mg of THC. Consumers who consumed the same amount of THC via an edible took longer to recover their driving skills. Most cannabis edibles in legal markets are dosed at 10mg per serving, and 100mg total THC per package.
“Overall, our results confirm that Δ9-THC impairs aspects of driving performance,” the researchers wrote. “There appears to be no universal answer to the question of How long to wait before driving? following cannabis use: Consideration of multiple factors is therefore required to determine appropriate delays between Δ9-THC use and the performance of safety-sensitive tasks.”
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Edible highs hit later and last longer
The differences between inhaled THC and ingested THC (via edibles) were significant. It’s widely known that the effects of THC and other cannabinoids will be felt within minutes by consumers who smoke or vape cannabis products, while an edible or beverage can take up to an hour or more to hit.
In their review of the scientific literature, McCartney and colleagues found that the intoxicating effects of edibles and beverages usually last much longer than inhaled products.
Those researchers found that smoking or vaping 20mg of THC diminished a driver’s reaction time for roughly four hours. But ingesting 20mg of THC via an edible or beverage diminished reaction time for eight hours, twice as long. The study’s data indicated a THC-impaired driver’s reaction time was diminished at a significant but not dramatic level.
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Heavy edible? Could be a 10-hour ride
“Our analysis indicates that impairment may last up to 10 hours if high doses of THC are consumed orally,” said McCartney, who works with the Australian university’s Lambert Initiative for Cannabinoid Therapeutics. “A more typical duration of impairment, however, is four hours, when lower doses of THC are consumed via smoking or vaporization and simpler tasks are undertaken.”
That impairment—which cannabis consumers may experience as feeling high, or stoned, or deeply relaxed, or sleepy, or mirthful, or creative—“may extend up to six or seven hours if higher doses of THC are inhaled and complex tasks, such as driving, are assessed,” McCartney added.
For the purposes of this study, McCartney and associates considered 10mg of THC to be a moderate dose. But a moderate dose for a regular consumer, they added, could be a high dose for an occasional one.
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Regular consumers show less impairment
As many cannabis consumers know, regular use can result in the body and mind building up a tolerance for cannabinoids ingested from sources outside the body, such as weed. This was also confirmed by the University of Sydney researchers.
Co-author Dr. Thomas Arkell, also from the Lambert Initiative, said: “We found that impairment is much more predictable in occasional cannabis users than regular cannabis users. Heavy users show significant tolerance to the effects of cannabis on driving and cognitive function, while typically displaying some impairment.”
Delta-8 THC is one of the hottest topics in cannabis right now. It’s a minor cannabinoid that can get you high like traditional THC, but much less so. It’s found in small amounts in the cannabis plant and is often converted from other compounds like CBD. If you haven’t heard of it yet, you surely will soon enough.
Reason #1 that interest in delta-8 is surging is its existence in a legal grey area: Delta-8 can be made from hemp and thanks to the 2018 farm bill, cannabis with less than 0.3% THC is considered hemp, and anything that naturally derives from hemp is federally legal.
That means if you convert hemp CBD into delta-8, you end up with a federally legal cannabis product that gets people high, although less high than traditional THC. Some states have begun to regulate delta-8, some not. Read more on what delta-8 is and its legality in this article.
Reason #2 people are so curious about delta-8 is because it’s supposed to be a much less intense, much more approachable experience than the high you feel from consuming traditional cannabis with THC.
So does it get you high? We put delta-8 to the test, for the people.
What is delta-8?
Is delta-8 less intense than THC?
To test out delta-8 THC, I slid to a dispensary in Portland, Oregon to grab up the 250mg pack (ten 25mg servings) of Smokiez Sour Blue Raspberry Gummiez. I chose Smokiez because their traditional gummies are some of my favorites, giving me a great comparative reference. Plus, when trying new products, it’s important to find reputable brands that you can trust to put out the good on a consistent basis.
With delta-8 expected to have less intense effects than traditional THC, I decided to try them in separate doses of 50mg and 100mg, or two and four gummies, respectively. Activation time on the package said 45 minutes.
I took each dose on an empty stomach for the fastest onset time possible, and then allowed a period of four hours to pass, since edibles are expected to peak within 3-4 hours. I did not consume any other cannabis that day, so I started from a completely sober state.
Here’s my experience.
NOTE: The following experience is a single human trial, not a true scientific experiment. Experience with cannabis, frequency of use, and your body chemistry all come into play when deciding how high one will get. Consumption results may vary.
I ate the first dose at 10:30am, and after about 30 minutes, I started to feel the familiar head and body buzz that let me know there’s some weed in my system. Or excuse me, hemp.
The first thing to know before discussing the delta-8 experience is my tolerance. I chain smoke joints all day, every day, with dabs tossed in the mix here and there. It would take a lot of weed to floor me at this rate.
However, with traditional edibles, it tends to be the opposite. They always creep up on me because I forgot I ate them and then BAM—it’s Couchlock City, USA. That’s why I usually stay away from them.
That said, normally, a 50mg dose of edibles would absolutely rock me to sleep within a couple of hours, but the delta-8 gummies produced a stimulating, sort of energetic experience that comes from a good morning wake ‘n’ bake mixed with a nice cup of coffee.
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It was almost like smoking a joint of CBD-dominant flower, where you feel alert, clear-headed, and ready for any obstacles the day may throw your way. Within less than an hour of eating those gummies, I was locked into Google Docs knocking out days worth of writing work.
Truthfully, I expected to feel absolutely nothing when I ate those two gummies. I was ready to hate. But the Smokiez delta-8 gummies experience had me blasting music, dancing around my Airbnb, and punching out sentences that writer’s block had been stifling for over a month.
Sometimes, my head can get pretty foggy from the weight of the world’s news and personal anxieties around them. It leads me to a state where it’s hard to even approach daily life, let alone daily work. Cannabis is one of my remedies for this, and delta-8 proved to have the same benefits that I get by smoking a joint and telling myself that everything is going to be all right. All without the sleepy comedown.
It was a really pleasant surprise, honestly. Something tells me delta-8 might actually be as advertised. It might really be the weaker version of THC that makes cannabis more approachable for people with lower tolerances.
By 12pm, the delta-8 high had started to subside, and at 2pm the only lingering effects of the high were dry mouth and dehydration.
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All in all, if I were to describe the high in one word, I’d say: energizing.
Never once did I feel a groggy comedown. Never once did I feel my body succumb to the THC. Instead, I felt productive, motivated, and happy. It was the same type of high I get from consuming strains like Apple Fritter, Super Silver Haze, and Chocolope.
This is opposed to traditional edibles, where it’s only a matter of time before I’m horizontal on the couch with the Roku remote in-hand ready to waste hours of life watching Joe Budden Podcast episodes on YouTube. With delta-8, I popped a few of those bad boys and locked into Google Docs for four straight hours. Ernest Hemingway could never.
So yes, based on personal experience alone, I’d say that delta-8 gummies do get you high, and that the high is less intense than smoking joints of traditional flower or eating traditional edibles.
I ate the 100mg dose of delta-8 gummies at 4pm. If I’m keeping it real, the experience felt exactly the same as the 50mg dose. I wasn’t higher or anything, it was just right back to a quick head and body buzz that never once tailed off into a sleepy comedown, even as I moved well into the evening.
I was low-key disappointed with that—I thought boys were about to take off for the moon. In the end, it showed me that I could probably pop delta-8 gummies all day long without feeling like I need a 48-hour nap to clear out the oh-my-god-I’m-so-high cobwebs I sometimes get from traditional THC.
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Does delta-8 THC get you high?
Yes, delta-8 definitely gets you high, but it was a lighter high than I’m accustomed to from smoking joints, taking dabs, and eating regular edibles.
These gummies were definitely less intense than the normal Smokiez fruit chews, and in the end, this home-cooked experiment left me feeling like delta-8 could be great for people who want an energizing experience from cannabis but don’t want to smoke joints or take dabs for it.
Or if you simply get way too high from joints and dabs and you’ve been running from cannabis and its many benefits, delta-8 could be the training wheels you’ve needed all along.
Most of the time, people expect edibles to hit hard and have you stuck to the couch in slump mode. Perhaps delta-8 is the solution to avoid that.
Or perhaps it’ll be outlawed before we get the chance to see.
How one woman is adjusting, getting older, and getting wiser about weed
When I first started consuming cannabis, I was a 21-year-old college student. My cannabis routine consisted primarily of shared bowls, bongs, and blunts packed with THC-dominant cannabis flower, and I typically only consumed on nights and weekends.
Just as it does now, cannabis helped me relieve stress, anxiety, pain, and depressive symptoms back then. It helped me fall asleep faster and sleep better as well. But in the near-decade that’s passed since my first toke, aging has changed my cannabis routine in so many ways. Everything from my preferred method of cannabis consumption to my dosing preferences to my THC tolerance is completely different now.
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How aging has changed my preferred method of cannabis consumption
Until my late 20s, smoking and vaping were my favorite ways to consume cannabis. As someone who has always used the plant to relieve stress, pain, and anxiety — and later in my cannabis journey, PTSD symptoms as well — I appreciated the instant relief inhalation provides.
As I age, however, I prefer sticking with edibles and tinctures, partially due to health issues that weren’t present in my life until 2019, but also because I’m more health-conscious in general now and I want to protect my lungs.
When asked about it, Tishler said he doesn’t think preference is the right way to look at one’s consumption methods.
“As a cannabis specialist, I think preference isn’t really the right way to look at it. Different routes of administration cause different outcomes, so the approach is best tailored to the symptoms,” he explains.
Mechtler says something similar: “In general, the best method for cannabis consumption depends on what is the person using the cannabis product for. Are they simply using it to ‘catch a buzz,’ or are they trying to treat an underlying health condition?”
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Mechtler recommends tinctures and capsules because they typically yield six to eight hours of relief for patients while inhaled products only yield two to three hours of relief.
Additionally, both Tishler and Mechtler discourage smoking and vaporizing cannabis since those methods put our health at risk. “I would not recommend smoking because it’s not good for us, which is something that becomes of greater concern to people who are older,” Tishler says.
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As an oncologist, Mechtler says he has a very hard time recommending a smoked or vaporized cannabis product to his patients. “This is something that is even more important now with the ongoing COVID-19 pandemic. One should really be doing everything they can to protect their cardiopulmonary system,” he says.
How aging has changed my dosing preferences and my THC tolerance
I moved from California to Missouri in 2019. I still can’t afford my Missouri medical marijuana card — but that’s only partially why my cannabis routine consists primarily of full-spectrum, hemp-sourced CBD products and has for nearly two years. Simply put: when it comes to THC, I feel like less is more.
When I was younger, smoking an entire bowl, taking multiple bong hits, or eating a 20 milligram edible in one sitting felt great.
For years, high doses of THC-dominant cannabis products and strains effectively squashed my anxiety and PTSD symptoms with little or no negative side effects.
But shortly after I turned 29, large doses of THC started making me feel worse. I’m not alone in this experience, either. Anecdotal evidence suggests age can play a role in how a person experiences THC. Additionally, the results of a 2007 study support a connection between age and THC sensitivity.
Over the course of the study, two age groups of rats were given THC and then put through tasks designed to test their stress and anxiety levels. The study results led researchers to conclude that the older rats were more likely to suffer from higher levels of stress and anxiety after consuming THC than the younger ones.
Whereas I used to smoke and vape almost exclusively, often several times a day, these days I prefer taking 15 to 30 milligrams of high-quality CBD two or three times a day. I feel like my current routine works beautifully to ease anxiety and promote sleep. And I love that there’s little risk for impairment or paranoia with CBD. Even when I do manage to get my Missouri medical marijuana card, I’ll probably keep consuming hemp-sourced CBD oils daily and consume low-dose THC edibles only.
Aging won’t necessarily affect your ideal dose or your THC tolerance in the same way it’s been affecting mine, though. Tishler says dose doesn’t seem to correlate well with age. “Some of my highest dose patients are the older ones, even if they started from completely cannabis naive,” he says.
What is the best quantity for a dose of cannabis?
Regarding anxiety and PTSD, Tishler says THC dose can have a very fine line, and crossing it exacerbates those conditions. “I also suspect that the mindset of the patient is very important to where that line lies, and as you age concerns about both existential issues as well as your cannabis use may contribute to shifting that line lower,” Tishler says. Indeed, a number of factors can affect a person’s cannabis high.
Why consistency is crucial for any cannabis routine
Ultimately, aging looks different for everyone, and no two bodies are exactly the same. There are multiple ways to have a healthy cannabis routine, and it’s entirely possible mine will change — possibly many times — as I continue to age.
But one thing is for certain: consistency is essential for any cannabis consumer.
“Sticking to a routine is key,” Tishler says. “Working with your cannabis specialist to find the right route and dose and then taking it consistently (like a medicine) leads to best benefit.”
Whatever your preferences regarding consumption methods and THC content, you can’t go wrong with this standard cannabis advice: start low and go slow.
And with the COVID-19 pandemic still raging, cannabis consumers of all ages should be extra careful to protect themselves and their lungs.
We’re probably all familiar with the belief that cannabis flower burning to “white ash” indicates it was grown right or is otherwise good bud. Similarly, we likely all know the old-school belief that holding in a hit gets you higher (“if you cough you don’t get off”), which was disproved by research over 30 years ago.
So if the long-held belief that holding in hits gets you higher is not true, yet persists, what about white ash?
Is there something about bud that burns to white that makes it better than bud that burns to black?
Leafly reached out to a team of cannabis experts, researchers, growers, and patients to try and ascertain what truth is behind the beliefs around white ash.
Before turning to the experts, Leafly wanted to see what folks were saying on social media about the white vs. black ash debate.
We saw three main responses:
People who felt a growing step called “flushing” was the cause of white ash and a sign of good bud;
people who felt it was a measure of moisture in the bud (too moist bud = black ash);
and people critical of the entire premise.
“A properly grown bud flushed of nutrients with water for the last 10 days of growth will give you a white ash when the bowl is cashed,” said Jake Sassaman.
“I used to think that was the case, but I have come to learn that it may not be indicative, actually, of residual salts, completed cure, or otherwise,” said Demetrius Daniels.
“My layperson’s understanding is that this is a rough measure of remaining water content,” said Jay Reynolds.
“For us old hippies, white ash is not a factor. Smoke to the last hit—as long as we can get high it’s good,” said Janet Benaquisto.
The Dank Diplomat and the star of Netflix’s Cooking on High, Ngaio Bealum, said, “I have noticed that white ash tends to indicate a better bud.”
Tappié Dufresne, a longtime cannabis patient and consultant who formerly worked at the historic early collective C.H.A.M.P., added, “White burning ash (from anything burning) indicates a clean combustion. You can think of campfires you might have watched. If the wood is green, it leaves a chunky charcoal.”
The ‘flushing’ controversy swirls
While there is some divide over what white ash signifies, there is pretty wide consensus around the importance of a weed grower’s common practice called “flushing.”
Hydroponic indoor growers “flush” the plant for the last 10 days before harvest by only feeding it water, instead of a nutrient mix.
Dufresne compared flushing cannabis with water to fasting for people, “It forces any stored nutrients to be used up by the plant and triggers a push to ripen.”
While Dufresne supports flushing, she also noted, “Even well-flushed flowers that are rushed through the drying and curing process will not burn perfectly.”
But what does the research on flushing say?
Flushing science is thin
Dr. Robert Flannery (Dr. Robb), an expert in cannabis biology, said, “There isn’t much research that supports this concept,” and pointed to a Master’s Thesis which found flushing “to be ineffective in removing any significant amount of nutrient from the bud.”
Dr. Robb is co-authoring The Cannabis Grower’s Handbook with Ed Rosenthal and Angela Bacca, which will be released this September and delves deep into flushing, how it is done, and if it actually does anything.
It specifically points to a lack of “double-blind studies that have been performed to test the efficacy of flushing,” but notes that despite that absence of research, “the overwhelming majority of cannabis growers flush.”
Josh Wurzer, the president and co-founder of SC Labs in California, said he personally “can taste a poor flush when smoking flowers.”
Why wet weed won’t burn white
While the majority of cannabis growers flush and it is a concern for some consumers, others wonder if black ash may be the result of too much water, rather than not enough.
Despite being able to taste the difference in flushed vs. not flushed flowers, Wurzer at SC Labs was clear that “black ash is a sign of incomplete combustion,” adding, “I’m not aware of a plausible explanation that a cause of poor combustion would be a poor flush.”
Wurzer listed the potential reasons for incomplete combustion, such as:
too much moisture in the flower (as is the case with a poor dry and cure);
a poorly rolled joint;
or a really resinous flower.
Wurzer said taste, not ash color, is “probably a better indicator” of good bud.
Of bowls and black ash
White ash may not have as much to do with the bud itself, but how it is smoked, specifically, in a joint or a blunt.
SC Labs’ Wurzer explained the science behind joints burning more:
“Joints/blunts also heat the material that is about to be burned, vaporizing both the resin and moisture in that part of the bud, which means that two of the major contributors to an inefficient combustion—and therefore black ash—are removed from the equation, or at least reduced before that part of the joint even combusts.”
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Additionally, Wurzer noted that “the airflow is much more optimized for an efficient combustion in a joint vs. a bong or bowl.”
That is why pipes tend to burn black while joints burn white.
It really comes down to if you like the smell, taste, and the high—not the ash, it seems.
White ash on its own is an insufficient proxy for quality; there’s too many other factors at play. (I mean, cigarettes burn pure white, and no one’s Instagramming their Camel Lights.)
So if it burns white and you like it—great! If it doesn’t—that can be OK, too.
What are your thoughts on the white vs. black ash debate? Leave us a comment and join the conversation.
Gastrointestinal (GI) illnesses are a frequent reason for using medical cannabis. These conditions include gastroesophageal reflux disease (GERD), two inflammatory bowel diseases — Crohn’s disease and ulcerative colitis — and irritable bowel syndrome (IBS).
The gut has two main functions, namely digestion of food and host defense, protecting us from foreign invaders like bacteria and viruses. The endocannabinoid system, which is widely distributed throughout the gastrointestinal system, is a key player in keeping these two important functions regulated. It is found in the gut’s nerves and in the cells of the immune system, working to maintain homeostasis of gastric motility (the muscular contractions that work to move food through the bowel), intestinal pain signaling, intestinal inflammation, and maintenance of the barrier of the gut lining.
The nerves in the gut are called the enteric nervous system, sometimes called the “second brain.” Cannabinoid receptors (CB1 and CB2) are found throughout these nerves. All disorders of the gut are thought to involve the enteric nervous system, making these receptors an attractive target for treatment when illness is present. Scientists have found that the number of cannabinoid receptors can increase (upregulate) in certain intestinal illnesses, indicating that the endocannabinoid system is mounting a response to try to restore balance.
In addition to cannabinoid receptors, other receptors, such as PPARs, GPR55, and TRPV1, are found throughout the gut and are involved in intestinal inflammation and pain. Since cannabinoids, such as tetrahydrocannabinol (THC) and cannabidiol (CBD), interact with these receptors, CB1 and CB2 are also therapeutic targets for treatment by anyone using cannabis medicine for gastrointestinal disorders.
Almost 80 percent of your immune system resides in the gut. The endocannabinoid system, including the CB2 receptors, is also present in these immune cells, ready to go into action to decrease inflammation when needed. However, if your endocannabinoid system is not working properly, it may not be able to mount the appropriate response to these triggers, leading to chronic intestinal symptoms.
Interestingly, people who have a mutation in the gene coding for one of the endocannabinoid system components are more likely to have IBS and chronic abdominal pain – evidence that endocannabinoid dysfunction may be one of the root causes of gut disorders.
GERD is very common, affecting 20 percent of all adults. GERD occurs when the stomach contents flow backward into the esophagus, causing symptoms of heartburn, chest pain, difficulty swallowing, and/or a sensation of a lump in the throat. GERD is often treated with medications; however, there are reports of possible increased risk of dementia and cancer from these drugs. Other interventions include altering the diet, remaining upright after meals, losing weight, and stopping tobacco use.
Animal studies have shown that cannabinoid stimulation of the CB1 receptor inhibited acid secretion and decreased damage and inflammation in the lining of the stomach. Preclinical research also showed that cannabinoid activation of the CB1 receptor kept the lower esophageal sphincter (the “gate” between the esophagus and stomach that works to keep stomach contents from flowing back into the esophagus) from relaxing, thereby decreasing reflux. In one human study, synthetic THC given to healthy volunteers was shown to decrease the reflux rate (although there were issues in the study since the dose was very high and caused side effects). It is clear that more research is needed to understand the role of cannabis in the treatment of GERD.
Clinically, some medical cannabis patients with GERD report benefits, although some do not. (As with all conditions, it is unclear as to exactly why some patients respond to cannabis and others do not.) Anecdotal reports from positive responders state they have fewer episodes of heartburn, and if they have an episode, taking cannabis decreases their discomfort.
Most patients finding benefits are including some THC in their cannabis regimen, as this seems to be the cannabinoid most helpful for GERD, at least anecdotally. Some patients report a low-ratio CBD:THC product (such as 1:1, 2:1, or 4:1) helps decrease GERD symptoms with less intoxicating effects compared to THC-dominant products. Two aromatic cannabis terpenes, limonene and terpinolene, may also be beneficial for GERD symptoms.
Inflammatory Bowel Disease
IBD is a general term that refers to chronic inflammation of the bowel. The two main IBD conditions are Crohn’s disease and ulcerative colitis. The Centers for Disease Control reports approximately three million adults were diagnosed with IBD in 2015, up from two million diagnosed in 1999. The exact cause of IBD is unknown, but recent scientific investigation reports the changes in the gut are due to “uncontrolled activation of intestinal immune cells in a genetically susceptible host.” Remember that immune cells are regulated by the endocannabinoid system, suggesting that endocannabinoid dysfunction may be a root cause of IBD and may serve as a therapeutic target.
Crohn’s disease can affect any part of the gut but most commonly the small intestine, causing inflammation, ulcers, pain, bleeding, diarrhea, and weight loss. Ulcerative colitis is a chronic inflammatory condition affecting the large intestine, causing symptoms similar to Crohn’s. Both conditions are associated with an increased risk of colorectal cancer. According to a recent article, “current therapeutic options are insufficient for a successful treatment leading to a high rate of disability and intestinal surgery in IBD patients.”
Activation of the CB1 and CB2 receptors in animal models of colitis reduces inflammation. In a review of 51 scientific studies on cannabinoid treatment of colitis (only two were in humans), twenty-four different compounds, including synthetic cannabinoids as well as THC, CBD, and CBG, were found to be effective in reducing the severity of colitis.
Studies done in a number of different countries show about 10 to 12 percent of people with IBD are using cannabis to treat their symptoms. Studies in humans are limited but promising:
A 2012 study investigating 11 patients with long-standing Crohn’s disease and 2 patients with ulcerative colitis reported that after 3 months of treatment, patients reported improvement in general health perception, social functioning, ability to work, physical pain, and depression. There was a statistically significant weight gain and increase in body mass index.
A 2011 survey of 30 Crohn’s patients in Israel revealed 21 improved significantly with cannabis, finding less need for other medication and reduced need for surgery.
A 2013 survey of 292 patients receiving care for IBD revealed approximately half reported either past or current use of cannabis. Of those, 32 percent reported medical use for abdominal pain, poor appetite, nausea, and diarrhea. Most reported that cannabis either completely relieved or was very helpful for symptoms. In this study, current users noted significant improvement in abdominal pain, poor appetite, nausea, and diarrhea.
In a 2013 study of 21 patients with Crohn’s disease who did not respond to conventional treatments, inhaled THC or inhaled placebo was given over 8 weeks. Complete remission was achieved in 45 percent of the cannabis group and 10 percent of the placebo group; 90 percent of the cannabis group had lower severity scores versus 40 percent of the placebo group. Three patients using cannabis were able to wean off steroids. The cannabis patients reported better sleep and appetite with no significant side effects. Interestingly, all patients who achieved remission relapsed within two weeks of discontinuing the cannabis treatment.
In 2019, two reports were published that reviewed hospital records through the National Inpatient Sample database, allowing researchers access to thousands of medical records. The first report looked at 615 hospitalized Crohn’s disease patients who used cannabis (legally or not) and compared them to Crohn’s patients who did not use cannabis. Cannabis users were found to have:
– Less stricturing disease (scarring built up secondary to chronic intestinal inflammation)
– Fewer bowel obstructions
– Fewer fistulas and abscesses
– Shorter hospital stays
– Fewer blood transfusions
– Less colectomy surgery (removal of the colon)
– Reduced IV nutrition requirements
The second report, using the same database of medical records, included 6,002 patients with Crohn’s disease (2,999 cannabis users and 3,003 nonusers) and 1,481 patients with ulcerative colitis (742 cannabis users and 739 nonusers). This review found:
– Crohn’s patients using cannabis had statistically significant lower incidence of cancer, less need for IV nutrition, less anemia, and shorter hospital stays with lower hospitalization costs; however, this report found an increase in fistula/abscess, GI bleeding, and hypovolemia (a decrease in circulating blood in the vessels).
– Ulcerative colitis patients using cannabis have statistically significant lower frequency of postoperative infections and shorter hospital stays with lower hospitalization costs; however, fluid/electrolyte imbalance and hypovolemia were increased.
These reports stated that “recreational” cannabis was used. There was no mention of the type of cannabinoids used (THC, CBD, or other), nor was delivery method (smoking, edibles, etc.) or duration of use reported. Both significant benefits and risks were found, warranting further human clinical trials.
I have evaluated many patients with gastrointestinal disorders who have had successful results with cannabis treatment. Almost all patients with Crohn’s disease or ulcerative colitis who have been seen in my office have exhausted conventional options prior to seeking cannabis treatment, finding that they either were nonresponders or experienced intolerable side effects. Similar to the findings already mentioned, my patients report that their symptoms, including nausea, poor appetite, abdominal pain, diarrhea, and bloating, respond to cannabis treatment.
Many patients prefer to inhale THC since the onset of relief is immediate. Patients who are reluctant to use THC-rich cannabis can use lower CBD:THC ratios, such as 1:1 or 4:1, with similar benefits but less chance of intoxication. THCA (the unheated, nonintoxicating version of THC ) was found to be the main phytocannabinoid helping to regulate intestinal inflammation. With the increased availability of tinctures containing THCA, and CBDA as well, patients are finding that daily use of these raw cannabinoids, sometimes combined with CBD, is effective for anti-inflammatory effects, helping to prevent flare-ups.
Irritable Bowel Syndrome
As the most common diagnosis made by gastroenterologists, IBS affects thirty-five million people in the US alone. IBS is characterized by episodes of abdominal pain, bloating, excessive gas, and altered bowel habits (constipation, diarrhea, or mixed type). No clear cause of IBS has been identified, although endocannabinoid deficiency is suspected. There usually are no abnormalities on blood tests or an endoscopy, making IBS a diagnosis based solely on the patient’s history and symptoms, after ruling out other causes. IBS sufferers often struggle with other conditions, such as fibromyalgia, migraine headaches, temporomandibular joint disorders, chronic fatigue, gastroesophageal reflux, anxiety/depression, or chronic pelvic pain. Chronic stress has been linked to both the development and/or the exacerbation of IBS and should also be a focus of treatment.
There are three published human studies of cannabis use for IBS, all employing synthetic THC as the study drug. Not surprisingly, one study reported all participants to have had side effects and no benefits; the study dose of 10 milligrams THC was clearly too much for the non-cannabis users who participated. The second study used lower doses, 2.5 milligrams or 5 milligrams of synthetic THC compared to placebo, and found participants with IBS diarrhea or IBS mixed type had a reduction in colonic motility, meaning THC slowed down how fast food moved through the gut. And the third study involved giving low-dose dronabinol (pharmaceutical THC) for two days and had no effect on IBS diarrhea. As mentioned before, findings from studies using single synthetic cannabinoid compounds are difficult to translate to outcomes in patients using whole-plant preparations.
Dr Bonni Goldstein
Clinically, many medical cannabis patients with IBS report benefits, most stating simply that “it helps calm the gut.” Some patients report substantial efficacy from low doses of THC taken in the evenings or just as needed when their gut is acting up. Others report using CBD preparations on a daily basis to control their symptoms. Additionally, some patients have reported that either THCA or CBDA, or both in combination, has helped with IBS, often with the patient achieving improvements in symptoms with low doses. Proper diet, regular exercise, and stress management support the endocannabinoid system, and in cases of IBS, patients find these additional interventions to be quite effective when combined with cannabinoid therapy.
It is important for patients with gut disorders to understand that long-standing inflammation will take time to respond to cannabinoid treatment. It may take eight to twelve weeks to experience significant benefits, although many report symptom reduction in the first few weeks. Edibles may cause further GI upset, so you should always read product labels to be sure you are not eating an ingredient that is a trigger for your symptoms. Terpenoids that have been found to specifically help the gut include terpinolene, beta-caryophyllene, limonene, and pinene.
This excerpt continues with a personal story of a young Crohn’s patient who benefited from a doctor-supervised medical cannabis regimen. Read more.
A tall, thin teenager with a crewcut, Robert came to my office with his parents seeking help in treating ulcerative colitis. Diagnosed two years prior, he was struggling with chronic abdominal; pain, bloody diarrhea, poor appetite, and weight loss. It was no surprise he expressed feeling depressed and hopeless. He had been on numerous treatments that did not help, and according to his parents, the pharmaceuticals he tried seemed to be making him sicker, not better. He had received multiple blood transfusions due to the anemia caused by loss of blood through his gut. At the most recent visit with his GI specialist, surgery to remove part of his colon was discussed, causing Robert much distress.
Prior to meeting with me, Robert’s parents caught him smoking cannabis. They were not surprised, as lately they had noticed something was different about him — maybe a lighter attitude and fewer complaints of discomfort. As a family, they googled “cannabis for ulcerative colitis” and decided to pursue this treatment with medical supervision, as they all agreed surgery would be a last resort. When I asked Robert how cannabis helped him, he reported that all of his physical symptoms were reduced, and that he felt “normal” for a few hours. He and his parents had concerns that he was buying cannabis from unknown sources and that he was at risk for getting into legal trouble. He stated maturely, “I feel like this could be my medicine, but I don’t want to be a criminal for using it.
I educated Robert and his parents about the endocannabinoid system, about the different phytocannabinoids, and about the promising, yet limited, research on cannabis use for Inflammatory Bowel Disease. I started Robert on low doses of a CBD:THC tincture (25:1) twice daily with the plan to increase every one to two weeks, aiming for a dose of 300 milligrams twice daily. We discussed using vaporized THC as needed for acute symptoms. After four weeks, he reported less diarrhea, less abdominal pain, and better appetite. He was sleeping better too and said his mood was improving. He continued to have blood in his stools, so THCA twice daily was added to the regimen.
Robert’s red blood cell count stabilized over the next six weeks. He gained weight and happily reported he had started playing basketball again, something he had not been able to do since his initial diagnosis. His lab tests revealed a decrease in the inflammatory markers, and although they were still elevated, the decrease was evidence that the inflammation in his body was starting to respond to treatment. Robert’s GI specialist is cautiously supportive of this treatment, as he too has seen Robert’s condition stabilize. Most importantly, Robert has reported a significant improvement in his quality of life, and for the first time in years, he feels optimistic about his future.
They say the endocannabinoid system (ECS) is as unique as a fingerprint, and cannabis affects us all differently. Company EndoCanna Health is exploring this by offering a DNA test that will show your body’s genetics and suggest a cannabis profile accordingly, as well as products for that profile.
This tool wouldn’t be with us today without a real Bob Ross of a happy accident—the moment Len May, CEO of EndoCanna Health, accidentally found an effective way to manage his ADD. According to May:
“I was kind of hanging out with some older kids, and they asked me if I wanted to smoke a cigarette—and I was like, yeah, you know, I’m dabbling with cigarettes, I’m gonna be cool—and the cigarette was actually filled with weed instead. After I got done coughing, I went back to class, and the windows in my head [referring to what it’s like to think with ADD] they sort of slowed down, and I could focus. So I found my medicine, it was mine.”
After getting kicked out of the house for cannabis—ironically, his parents now use his cannabis formulations—he became a cannabis activist and started working in medicinal genomics, which eventually led to EndoCanna Health, and the ability to use cannabis on a truly personal level.
How does EndoCanna Health’s DNA test work?
While receiving the $199 test can take a month or two, taking the test is a matter of seconds: carefully swab the inside of your cheek, then pop the swab into a tube. After registering your test into their HIPAA-compliant, fully anonymous portal, seal the swab and tube in a plastic bag, pop it into the provided paid envelope, and send ‘er off to the lab. If you have DNA data already, it’s faster and only costs $49.95.
Once your results are ready, log into your profile, which will have an itemized breakdown of your report and suggestions for types of cannabis. The report is broken down into:
Cognitive function & behavior
Musculoskeletal & immune
Pain, nausea, & neurologic
THC side effects
Digging into my report
Clicking through the various reports shows how cannabinoids interact with your genetic profile in specific ways. For instance, clicking on “Anxiety” brings three more reports: “Fear Extinction,” “PTSD,” and “Stress Reactivity.”
Under “Fear Extinction,” for example, is this summary of my specific DNA marker findings, as well as suggestions for types of cannabis to use:
In this case, it suggests I start using high-CBD ratio products, as well as cannabis with terpene profiles that include linalool and beta-caryophyllene. These responses are called “formulations,” and my report suggests seven different ones for specific needs.
Also, the Personalized Wellness Plan links to relevant scientific studies and provides a link to products that match the formulation.
CEO May explained that although EndoCanna Health does sell terpene blends used in some recommended products, they don’t profit directly from sales of products recommended on the Wellness Plan: “We look at certificates of analysis from different product manufacturers and run them to a matching algorithm, and we look for several things: Number one, we look for the percentage of CBD, THC; Secondary, terpene profile; and then some others, like essential oils.”
How to use your cannabis DNA test results
“The best way to get the most out of your results is to understand what your genetic predispositions are to avoid an adverse effect and then to understand which products you can actually take,” said May.
With your test results, you’re equipped to treat symptomatic conditions based on specific genotypes in your body. “If you have a predisposition to anxiety or stress reactivity, you will know that there are certain cannabinoid and terpene profiles that can actually turn that genetic expression on,” said May.
For example, if you have a marker associated with not producing endocannabinoids when anxious—as the body ought to—you’ll be able to know what kind of cannabis can be substituted effectively.
And it’s a living document as well, meaning it will evolve as research does. “We have a HIPAA-compliant portal that is dynamically built with lifetime updates, meaning that if there is any research that is happening now that gets published, we provide that as an update to your report on a lifetime basis. And we’re fully secure and anonymized. All the data resides on Amazon’s AWS; it’s fully encrypted,” said May.
May continued to speak on what’s ahead: “The future is this whole feedback loop: It’s the ability to be able to get a response from people, how you know product ‘A’ is really working for you, learn from your experience, and then be able to produce better individualized products.”
EndoCanna Health is a research lab as well, working on studies all over the world. The company is also looking into expanding the use of epigenetic data and using biomarkers, like Fitbit info, to create a dashboard that will further personalize your experience.
Is the test worth it?
My take is probably obvious by now: I think this is a fantastic resource. I love that it breaks down which cannabinoids and terpenes will help various aspects of my body makeup. As a medical cannabis user, I find this especially relevant—it also confirmed I’m high-risk for flu severity—but these reports will also be helpful for anyone without any medical issues because we all have different bodies and cannabis will interact with each body differently.
EndoCanna Health is also looking to collaborate on research, even with competitors, because “the only way to remove this ridiculous stigma is through science,” said May.
I love it. Let’s science our way from being disregarded as just stoners to having data to improve specific conditions or for overall health, and knowing how best to use cannabis for those specifications.
And all this magic started with a teenager trying to smoke a cig, and failing. C’est la vie, eh?
But how does cannabis affect the immune system as a whole? If you’re a regular consumer, you may have pondered whether cannabis weakens or boosts your immune system. Can frequent cannabis use render you more prone to infections or contagious diseases?
As it turns out, research into cannabis and the immune system hasn’t historically piqued the interest of scientists. However, as our understanding of the effects of cannabis on the body becomes more sophisticated, we need to also broaden our knowledge of how cannabis influences the immune system.
Present evidence suggests that cannabis can suppress immune system function. While this can be helpful for individuals with autoimmune illnesses, it may not be so beneficial for those with functional immune systems.
Meet your immune system
The immune system is one of the body’s most sophisticated networks. A collection of specialized cells, endogenous chemicals, and organs work in concert to ward off pathogens and infections, protecting the health and homeostasis of the body.
The immune system is multifaceted, and its core components that actively combat infection include white blood cells, the complement system, antibodies, the lymphatic system, the spleen, the thymus, and bone marrow, but we’ll mainly talk about white blood cells.
Memories of every microbe previously defeated by the immune system are logged in white blood cells. These memories enable the fast tracking and elimination of infections that have already been experienced. The immune system is also responsible for detecting and eradicating malfunctioning cells.
The knowledge we have about the interaction of cannabis with specific immune elements is limited. While there is some research exploring the effects of cannabinoids on white blood cell count and the lymphatic system, we know less about how cannabis impacts the thymus or the complement system.
Cannabis, the endocannabinoid system, and the immune system
An elegant connection exists between the body’s endocannabinoid system (ECS) and its immune system. The ECS is generally considered to be one of the gate-keepers of the immune system, preventing the onset of overwhelming inflammatory responses that may result in disease. The ECS can also influence the function of immune cells.
CB1 and CB2 receptors in the endocannabinoid system mediate the effects of cannabis within the immune system. The two major cannabinoids, THC and CBD, appear to have distinctive effects on the immune system due to their unique interactions with cannabinoid receptors. Abundant literature suggests that cannabinoids affect the functions of most types of immune cells.
A 2020 review found robust evidence that CBD suppresses certain inflammatory responses in the immune system and may induce cellular death in immune cells. Immune cell death isn’t always a bad thing—it’s a normal part of the cellular life cycle, and helps to protect a person by alleviating inflammatory responses.
Like CBD, THC also suppresses immune activity, dialing down inflammatory responses. THC has also been shown to alter the function of immune cells responsible for antimicrobial activity.
How does cannabis affect the immune system?
When scientists discuss cannabis and the immune system, they often discuss its effects as immunomodulatory or immunosuppressive. Immunomodulation refers to any therapy that modifies the immune system response. When cannabis suppresses the expression of aspects of the immune system, this form of modulation is known as immunosuppression.
It’s vital to point out here that marijuana’s ability to subdue or suppress immune system cells can be useful if the immune system is dysregulated and in need of suppression. If not, immune suppression might not be helpful.
Research published in 2017 indicated that both CBD and THC have an immunomodulatory effect on the human intestinal lymphatic system, the major host of immune cells. The lymphatic system also contains more than half the body’s lymphocytes—white blood cells that play a critical role in finding and destroying foreign cells or substances that have infiltrated the body.
The study’s authors found that oral administration of CBD and THC with fats resulted in extremely high cannabinoid levels in the intestinal lymphatic system: CBD concentrations in lymph cells were 250 times higher than in plasma, while THC concentrations in lymph cells were 100 times higher than in plasma.
So, what’s the significance of this? For individuals with autoimmune diseases, cannabis can achieve higher concentrations in the lymphatic system and suppress unhealthy inflammatory immune responses more successfully.
The pros and cons of cannabis as an immunosuppressant
While the immunosuppressive properties of cannabis may be just what the doctor ordered for autoimmune patients, they can cause problems for other cannabis users.
Research carried out in 2003 on healthy volunteers suggests that regular cannabis may subdue immune function. Cannabis users were found to have fewer proinflammatory cells and more anti-inflammatory cells.
While less potential for inflammation may sound like a win, in this case, it was associated with a significant reduction in white cell functionality, and impaired white cells can mean a hindered ability to fight off infections. Regular cannabis users also had decreased amounts of natural killer cells, which limit the spread of tumors and microbial infections.
The study also indicated that there may be a dose-response relationship between cannabis use over an individual’s lifetime, and a decrease in certain immune system markers, meaning those who use cannabis regularly may be more susceptible to the progression of infectious disease.
What about the effects of cannabis on extremely immunocompromised individuals? Unfortunately, cannabis can substantially decrease infection-fighting cells in people undergoing chemotherapy. This suppressive response may further add to the detrimental effects of chemotherapy on immune systems of those with cancer.
Research on people with HIV+ and AIDS, who are particularly vulnerable to infections, however, indicates that there is no firm evidence that cannabis adversely affects immune function.
Instead, findings suggest cannabis use among HIV+ patients may enhance the immune system by producing a statistically significant decrease in viral load and an increase in CD4 cells. CD4 cells can be considered a marker that indicate the robustness of the immune system.
While existing research allows us to glean insights into cannabis and the immune system, we need more rigorous data to paint broad brushstrokes. According to the most recent 2017 report from the National Academies of Science, Engineering, and Medicine (NASEM), there’s insufficient research on the effects of cannabis or cannabinoid-based medicines on the human immune system to draw firm conclusions.
Cannabis in the time of coronavirus
Within the current global climate shaped by COVID-19, there’s an impulse among the research community to enhance our understanding of the impact of cannabis on the immune system. Some cannabis researchers are currently channeling their focus into investigating whether cannabis may be helpful or harmful in treating COVID-19.
More profound exploration into the effects of cannabinoids on the immune system is also being encouraged. Watch this space as new frontiers are forged.
In order for a prescription drug to reach the market, it must be extensively studied, first in animal and then in human clinical trials. Safety, efficacy, and risks must be determined. But as anyone who has seen a commercial for a prescription drug knows, there are still side effects. There are risks in stopping a prescription. And, of course, there are the risks of addiction.
Prescription opioid painkillers have increased drastically from common-use pill to massive public health crisis. At the same time, the perception of marijuana has shifted away from it as a gateway drug to using it as medicine.
Now, several recent studies show that public opinion is shifting to the point of substituting cannabis for opioids and other prescription drugs that have high risks or low efficacy. In addition to opioids, drug substitution is most common for benzodiazepines, like Valium or Klonopin, and antidepressants.
The benefits of substituting a substance for an addictive drug seem obvious, but there is a serious hidden risk in doing so without talking to a doctor. For example, with CBD, its interactions with prescription drugs have barely been studied. Complications can arise from drug interactions and withdrawal symptoms, resulting in incorrect dosages and potentially unknown side effects.
Patients are substituting prescriptions with cannabis
With unregulated whole-plant and hemp-derived CBD easily available online and in grocery stores across the United States, as well as recreational and medical cannabis in shops in the US and Canada, some people are doing just that.
One specific substitution holds promise, but also danger: benzodiazepines.
Benzos—such as Klonopin (clonazepam) and Valium (diazepam)—are commonly prescribed for anxiety, insomnia, seizures, alcohol withdrawal, and muscle spasms, all of which also have the potential to be treated with medical cannabis, especially CBD. But unlike CBD, benzodiazepines have been around the scientific block, completing the clinical trial process and landing on the market in the 1960s. Also unlike CBD, they are known to be addictive.
“There’s this great opportunity because of the opioid crisis to find alternatives,” said Dr. James Corroon, Medical Director at the Center for Medical Cannabis in California, who published a study on cannabis substitution for pharmaceutical prescriptions last year. Of 2,774 participants, 46% reported substituting cannabis for a pharmaceutical drug. “There’s reason to be hopeful,” he said, “but we need more data.”
There’s also reason to be concerned. Self-identified “medical” consumers were about five times as likely to substitute drugs with cannabis than recreational consumers, according to the study. And almost a quarter of recreational consumers also reported substitution.
Non-prescribed swapping of THC or CBD for a prescription drug often occurs accidentally at first: A chronic pain patient might smoke marijuana recreationally and notices it helps; an insomnia patient might eat a CBD chocolate for anxiety but then is able to sleep; a person might get a medical marijuana card for anxiety and discover it helps with pain and insomnia.
While this might seem like a serendipitous coincidence for patients, the pattern is a warning to doctors. “These people aren’t getting the right care,” said Dr. Corroon. The concern is with drug interactions.
If you add CBD to a drug regimen of an opioid or a benzo, it creates an amplification effect, Dr. Corroon explained. With CBD and Valium, for example, the liver metabolizes CBD first. The Valium is then sent back into the bloodstream, allowing the same dose to last longer. As a result, the patient may be unintentionally overmedicating. This also means a patient could be prescribed a lower dose of Valium to experience the same relief.
This can be great if a healthcare worker is supervising a patient and their drug substitutions, but doses of benzos need to be slowly decreased to be safely stopped, regardless of whether another drug is added.
Rapid decreases of any drug can be dangerous. Benzodiazepines depress the central nervous system and an abrupt change can leave the brain struggling for balance. Benzodiazepine withdrawal can cause a return of symptoms, additional anxiety, insomnia, and flu-like symptoms. More severe symptoms include panic attacks, hand tremors, depression, and seizures.
Without medical advice and supervision, a person could experience withdrawal, unnecessarily low or high doses, or vacillation between the two as anxiety decreases and returns, said Dr. Corroon.
Can cannabis help?
Cannabis treatment is being broadly studied as a partial or full substitution for opioids, but research is just beginning on its possible use in reducing benzodiazepine use.
“There is a role for benzodiazepines in clinical practice,” said Dr. Chad Purcell, a surgical resident at Dalhousie University. But there’s an issue with benzodiazepines that is similar to that of opioids, he said.
In a small study, Dr. Purcell and his associates analyzed information provided by patients new to cannabis treatment who were already taking benzodiazepines. Almost a third stopped their benzodiazepine treatment within two months. And almost 45% ended use by four months.
“There seems to be something at play here,” Dr. Purcell said. But he cautioned against drawing a direct line between the two. Just because two things happened—starting cannabis and stopping benzodiazepines—doesn’t mean one caused the other.
Another recent study, led by Dr. Phillipe Lucas, VP of Patient Research at cannabis producer Tilray, showed high trends of cannabis substitution across all types of prescription drugs.
Dr. Lucas and authors analyzed cannabis use patterns and substitutions of 2032 Canadian medical cannabis patients who responded to a survey.
Many participants reported more than one substitution. About 45% reported substituting cannabis for alcohol, 31% substituted it for tobacco, and 26% substituted it for illicit drugs. A whopping 69% reported substituting cannabis for prescription drugs.
Unsurprisingly, opioids were the most common among pharmaceutical substitutions, at 35%. Antidepressants and anti-anxiety prescriptions came in close behind at 21%.
Detailed questions revealed that chronic pain and mental health issues were the two most common reasons participants took cannabis, both at just under 30%.
Chronic pain is often accompanied by mental health conditions, especially anxiety and insomnia, said Dr. Lucas. It’s a common trifecta of diseases and a troubling one. The conditions can exacerbate each other and the knot of symptoms can be difficult to untangle. It’s not uncommon for endless pain to cause severe anxiety and prevent sleep, Dr. Lucas said. Roughly half of participants reported experiencing all three as primary symptoms, according to the study.
Patients experiencing this medical triad often take more than one daily prescription as treatment, so it’s not surprising that many study participants substituted for more than one drug, Dr. Lucas explained. And it’s possible that, if a cannabis substitution could more effectively treat a root cause of chronic pain, medications for anxiety, insomnia or depression could become unnecessary.
For those people who are making a conscious choice to substitute, and doing so with medical guidance, there seems to be only an upside. It’s the people who accidentally substitute or self-prescribe that worry Dr. Lucas. “It gives me great concern.”
Stay informed and healthy
Always talk to your doctor before starting or stopping a new medication. Ask about potential prescription interactions and options. If you already take a prescription medication, talk to your prescribing physician about your marijuana and/or CBD use.
Living inside and on each of us is a vast population of bacteria, fungi, protozoa, and viruses. Cumulatively, the microbiome includes as many cells as the human body and encodes 100 times more genetic material than the human genome. Up to 1,000 different species of bacteria live in the gut alone.
With this knowledge has come the realization that the microbiome is a key player in human health, affecting everything from mood to metabolism. Microbiota inside the gut – a hollow tube extending from the esophagus through the intestines to the anus – play a huge role in human disease. Disturbances to this system, also known as the gastrointestinal or digestive tract, have been associated with obesity, cancer, and neurodegenerative disorders such as Parkinson’s and Alzheimer’s disease.
How it all works is a subject of ongoing scientific inquiry, one whose central discoveries have been widely publicized in popular and mass media in recent years. Yet there’s an important aspect of the link between human health and the microbiome that has received almost no attention outside the often obscure world of scientific journals: the role of the endocannabinoid system (ECS).
Current thinking suggests that the ECS serves as a sort of bridge between bacteria and the body itself, including the brain, relaying signals back and forth in a symbiotic, mutually beneficial relationship. At least that’s how it should be – but chronic imbalance or impairment of the gut microbiome, also called dysbiosis, can harm physical and mental health.
In the most basic sense, humans and other animals influence the “bugs” in their gut primarily through their diet, including the intake of so-called probiotic foods that promote a healthy microbiome. These bugs in turn help break down food and make nutrients more available to the body. We provide them sustenance and an amenable place to live, and they help us extract as much nutrition as we can from food in the digestive tract.
This in itself is awe-inspiring. But it also turns out to be incomplete. Groundbreaking research has shown that we also impact our gut microbiome through not only exercise and certain pharmaceuticals but also the consumption of cannabis, all via the common path of the ECS.
Cannabis for Gut Health
Interactions between gut microbiota and the endocannabinoid system were first explored in 2010. A Belgian research team showed that altering the gut microbiome of obese mice through prebiotics, foods that promote the growth of beneficial bacteria, altered ECS expression in fat tissue with implications for lipid metabolism and fat cell formation.1
More evidence came in 2015, when researchers in Canada administered a daily regimen of THC to mice sustained on a high-fat diet. Gut microbiome health in these animals improved after 3 to 4 weeks to more closely resemble that of animals fed a healthy, balanced diet.2
Few studies have investigated the effects of cannabis use on the human gut microbiome, but in 2017, researchers found key differences among 19 lifetime users and 20 non-users. Cannabis users possessed bacteria populations associated with higher caloric intake but lower BMI, though diet was thought to also play a role.
In 2018, researchers used archived anal swabs to assess the microbiomes of HIV-positive individuals. They found that cannabis use was associated with decreased abundance of two strains of bacteria linked to obesity.
Scientists are still trying to understand the details. But evidence is accumulating that the endocannabinoid system interacts directly and bidirectionally with bacteria in the gut, influencing the activity and makeup of the microbiome while simultaneously helping to transmit its messages to the body and brain. What’s more, microbiome health may be modified and even improved through plant cannabinoids, including both THC and CBD, as well as through the body’s own endocannabinoids, anandamide and 2-AG, whose production is stimulated through exercise and the consumption of certain foods.34567.8
A Pioneering Study
Just as the makeup of our microbiome depends on more than diet, the bacteria living in our gut do more than simply break down food. They also help regulate the epithelial barrier, a critical protective layer lining the interior of the long, narrow “tube” we call the gut or gastrointestinal tract. How do they do it? At least in part through interactions with the ECS, especially CB1 receptors, according to a pioneering 2012 study whose implications are still being sorted out.9
The epithelial barrier plays a hugely important role in maintaining overall health and warding off disease, says University of Calgary professor and researcher Keith Sharkey, who has studied the gut for decades and, more recently, both the microbiome and the ECS. He also served as senior author of the aforementioned 2015 study in which THC was administered to mice.
“The epithelial barrier is very crucial to maintaining what we call homeostasis, or the normal body’s functions,” Sharkey says. “The control of that fine lining is extremely carefully managed by the body. We have developed as mammals this very intricate control system, which prevents damage or quickly repairs damage, to prevent further erosion of our bodies. The bacteria we have in our gut contributes to that system. And it seems that the ECS is a very important control element.”
Sharkey is currently leading research to confirm whether CB1 receptors play a role in the acute regulation of epithelial barrier function. Preliminary evidence supports this hypothesis, he says.
Though he isn’t investigating concurrent changes to the microbiome, a link would make sense given that gut bacteria interact extensively with the epithelial barrier. “We live in a mutualistic symbiotic relationship,” Sharkey says.
Targeting the Microbiome
This all points in a predictable direction. If the ECS communicates with both the gut barrier and the microbiome, whose health is essential to human well-being, and we know we can manipulate the ECS through diet, exercise, and cannabis-derived compounds, might there be other ways to target the microbiome through the ECS in order to achieve specific health outcomes?
It’s a question the pharmaceutical industry has been actively investigating, says Cris Silvestri, a professor at Laval University in Quebec and Canadian Excellence Research Chair on the Microbiome-Endocannabinoidome Axis in Metabolic Health. Though no drugs have yet been developed for this purpose, Silvestri says the fast-growing field could start producing answers within the next five years that will point directly to pro- or post-biotics that can be used to tweak the gut microbiome via the ECS.
In fact, Silvestri and colleague Vincenzo DiMarzo say they’re already working with a pharmaceutical company on related research – though they can’t provide any details. Silvestri was, however, able to discuss another research project under development with the Quebec government, which is hoping to learn more about interactions between cannabis and the gut microbiome following Canada’s legalization of cannabis edibles earlier this year, Silvestri says.
“We’re in discussions for a project with the government to understand how edibles are going to affect your gut microbiome, and how is that potentially going to affect your response to edibles,” he says. “Is the gut microbiome going to change those cannabinoids, make them more or less active?”
Silvestri is also involved in two additional studies that will shed more light on this complex relationship. One is investigating effects on the gut microbiome of genetic modulation of the ECS, which increases 2-AG levels and suppresses CB1 activity in treated mice. This builds on research published in January 2020 by the same team showing that experimentally controlled alteration of the gut microbiome resulted in significant changes to gene expression and signaling within the endocannabinoidome, a broader system of receptors, enzymes, and lipid mediators related to the ECS.10
The other current study looks at ECS levels in the brains of so-called germ-free mice, which have no microbiome, and associated impacts on behavior and anxiety. It also evaluates effects on both after the introduction of a microbiome through a fecal microbiota transplant.
“The hope is that there will be therapeutic applications in the end,” Silvestri says. “The drive comes from being able in the future to harvest the functionality of these bugs to improve human health.”
THC & COVID-19
A cannabinoid science lab led by Prakash Nagarkatti at the University of South Carolina is also pioneering investigations into the ECS, the gut microbiome, and disease. It may even have found a clue for treating one of the most harmful complications of COVID-19 in some patients.
In a June 2020 study published in Frontiers in Pharmacology, Nagarkatti and colleagues demonstrated that administering THC to mice affected with a form of acute respiratory distress syndrome (ARDS) could stop the condition in its tracks.11 A severe consequence of the runaway immune response known as a cytokine storm, ARDS occurs in a small percentage of COVID-19 patients but is often fatal.
“We have a mouse model of ARDS, where we inject Staphylococcal enterotoxin B [a bacterial toxin], and the mice die within four or five days because of cytokine storm and ARDS in the lungs,” Nagarkatti says. “And we found that if you give THC, it cures the mice. They are just running around healthy. That was amazing.”
Nagarkatti doesn’t know exactly how it happens, but he does know it involves the microbiome. “What we found was that THC was changing the gut microbiome, as well as the microbiome in the lungs, and there were similar changes in the gut as well as in the lungs, and then on top of that, when we transplanted the fecal material from the cannabinoid-injected mice into the normal mice, even they became resistant to the ARDS or cytokine storm.”
Though this was demonstrated in mice and is therefore not directly transferable to humans – or COVID-19, for that matter – this is perhaps the first evidence that cannabinoids’ alteration of the gut microbiome can play a role in suppressing the systemic inflammation seen in a cytokine storm, Nagarkatti says.
Interestingly, in one of its first papers on the ECS and the microbiome back in 2017, Nagarkatti’s lab also demonstrated that treatment with a combination of THC and CBD altered the gut microbiome in mice in a way that reduced inflammation, in this case with beneficial implications for autoimmune disease.12
“Suppressing inflammation in the colon as well as systemically is very critical for preventing any type of disease, because right now inflammation is considered to be the underlying cause of everything, not only autoimmune disease but cardiovascular and neurodegenerative diseases, PTSD, Alzheimer’s, obesity, cancers, COVID-19,” Nagarkatti says. “You name it and there is inflammation.”
While the molecular mechanisms still need to be worked out, the ECS plays an important role in modulating inflammation through gut microbiota.13 Nagarkatti reports: “THC alters the microbiome in the gut in a way that seems to be beneficial in suppressing inflammation because bacteria that are favored by THC or cannabinoids seem to produce short-chain fatty acids that suppress inflammation.”
Nagarkatti’s lab has also shown that THC treatment in mice leads to increased levels of bacteria in the beneficial genus Lactobacillus, often found in fermented foods and dietary supplements.14
Otherwise researchers know little about which specific “bugs” from among the roughly 1,000 species of bacteria in the gut are modulated by the ECS, or which species are themselves able to modulate the ECS, says Silvestri.
Indeed, there remains much more to learn about interactions between the ECS and the microbiome. Sharkey has his own list of unanswered questions that could become research priorities as the field progresses.
“We don’t quite know if it’s happening throughout the gut or if it’s restricted to certain regions of the gut,” he says. “We don’t know the interactions between various dietary constituents and the way that they change the microbial components of the gut as well as the ECS. We don’t know how many constituents of the cannabis plant are able to regulate the gut microbiome. We’ve yet to understand how the body’s own endocannabinoids really regulate epithelial barrier function.
“There are very, very many unanswered questions, but they are exciting because the consequences have the potential to be important for health,” he continues. “Almost daily when I look in the literature now, a new thing pops up that links the gut to bodily health: gut-heart connections, gut-lung connections, gut-kidney connections. So it would not surprise me to see a role for the ECS in many of those links. And we’re just scratching the surface of that right now.”
Nate Seltenrich, an independent science journalist based in the San Francisco Bay Area, covers a wide range of subjects including environmental health, neuroscience, and pharmacology.
Copyright, Project CBD. May not be reprinted without permission.
Among women who enjoy marijuana, there’s no shortage of anecdotal evidence that adding a bit of cannabis can bring a thrill to the bedroom, and in states where the drug is legal, marketers have capitalized on that claim. THC-infused lubricants promise increased arousal and better orgasms, and some sexual health advocates have built entire careers on cannabis-enhanced intimacy. But is there anything behind the hype?
While researchers are still trying to tease out the precise relationship between cannabis and sex, a growing body of evidence indicates the connection itself is very real. The latest study, which asked women who use marijuana about their sexual experiences, found that more frequent cannabis use was associated with heightened arousal, stronger orgasms and greater sexual satisfaction in general.
“Our results demonstrate that increasing frequency of cannabis use is associated with improved sexual function and is associated with increased satisfaction, orgasm, and sexual desire,” says the new study, published last week in the journal Sexual Medicine.
“Increased cannabis use was associated with improved sexual desire, arousal, orgasm, and overall satisfaction.”
To reach their conclusions, the team analyzed online survey results from 452 women who responded to an invitation distributed at a chain of cannabis retail stores. Researchers asked respondents about their cannabis use and had each fill out a Female Sexual Function Index (FSFI) survey, a questionnaire designed to assess sexual function over the past four weeks. The survey scores six specific domains, including desire, arousal, lubrication, orgasm, satisfaction and pain.
“To our knowledge,” the authors wrote, “this study is the first to use a validated questionnaire to assess the association between female sexual function and aspects of cannabis use including frequency, chemovar, and indication.”
Generally speaking, a higher FSFI score is understood to indicate better sexual function, while a lower score indicates sexual dysfunction. Comparing frequency of cannabis use to each participant’s FSFI score, the researchers determined that more frequent consumption was associated with lower rates of sexual dysfunction.
“For each additional step of cannabis use intensity (ie, times per week),” the report says, “the odds of reporting female sexual dysfunction declined by 21%.”
“We found a dose response relationship between increased frequency of cannabis use and reduced odds of female sexual dysfunction.”
Women who used cannabis more frequently had higher FSFI scores in general, indicating better sexual experiences overall. More frequent consumers also had higher specific FSFI subdomain scores—indicating things like greater arousal and better orgasms—although not all of those differences reached the threshold of statistical significance.
Another weak relationship showed that women who used cannabis frequently reported lower levels of pain related to sex.
“When stratified by frequency of use (?3 times per week vs <3 times per week), those who used more frequently had overall higher FSFI scores and had higher FSFI subdomain scores except for pain,” the study says.
The research doesn’t shed much light on what marijuana products might work best for sexual stimulation, however.
“Our study did not find an association between cannabis chemovar (eg, THC vs CBD dominant), reason for cannabis use, and female sexual function,” the researchers, who included members of the Stanford Medical Center’s urology department and the medical director of the Victory Rejuvenation Center, wrote. “Neither, the method of consumption nor the type of cannabis consumed impacted sexual function.”
Researchers said a number of mechanisms could explain the overall results, noting that prior studies have postulated that the body’s endocannabinoid system is directly involved in female sexual function. It’s also possible, authors wrote, that cannabis could be improving sex by reducing anxiety.
“As many patients use cannabis to reduce anxiety,” the report says, “it is possible that a reduction in anxiety associated with a sexual encounter could improve experiences and lead to improved satisfaction, orgasm, and desire. Similarly, THC can alter the perception of time which may prolong the feelings of sexual pleasure. Finally, CB1, a cannabinoid receptor, has been found in serotonergic neurons that secretes the neurotransmitter serotonin, which plays a role in female sexual function thus activation of CB1 may lead to increased sexual function.”
As the study notes, cannabis’s potentially positive effect on women’s sexual function was first noted in research from the 1970s and ’80s, when women in research interviews who used cannabis reported better sexual experiences, including more intimacy and better orgasms. But subsequent research has yielded mixed results. Some studies have found that women’s orgasms were actually inhibited by cannabis use. Authors of the new report said that past studies used interviews rather than a validated questionnaire to conduct research.
“The mechanism underlying these findings requires clarification,” the authors said of their report, “as does whether acute or chronic use of cannabis has an impact on sexual function. Whether the endocannabinoid system represents a viable target of therapy through cannabis for female sexual dysfunction requires future prospective studies though any therapy has to be balanced with the potential negative consequences of cannabis use.”
Yet another study, however, cautions that more marijuana doesn’t necessarily mean better sex. A literature review published last year found that cannabis’s impact on libido may depend on dosage, with lower amounts of THC correlating with the highest levels of arousal and satisfaction. Most studies showed that marijuana has a positive effect on women’s sexual function, the study found, but too much THC can actually backfire.
“Several studies have evaluated the effects of marijuana on libido, and it seems that changes in desire may be dose dependent,” the review’s authors wrote. “Studies support that lower doses improve desire but higher doses either lower desire or do not affect desire at all.”