Can cannabis help with weight loss?

Whisper the word cannabis and there is a good chance you’ll think of the munchies. Late-night fridge raids are synonymous with bleary-eyed stoners, so much so, that savvy sellers on Etsy are doing a roaring trade in magnets designed to keep the munchies at bay.

Logic would have it that weed is a nightmare for the waistline, but the relationship between cannabis and weight isn’t as simple as it seems. While cannabis might make us eat more, it could help us weigh less.

The science behind the munchies

When high, many people experience an enhanced appetite, often in the form of intense cravings for sweet, salty, or carb-rich food. Getting the munchies is one of the most common side effects of smoking or consuming cannabis, documented as early as 300 AD. 

In terms of what causes the munchies, we know that cannabis is the culprit, but what’s going on inside the brain to cause this insatiable urge to eat?  

There are several theories for this, but it is likely a combination of different mechanisms – all of which are initiated in response to THC, or tetrahydrocannabinol, the mind-altering molecule in the cannabis plant. 

The prevailing idea is that THC, by activating type 1 cannabinoid receptors (CB1) in the brain, stimulates several brain pathways that cause the release of ghrelin, famously termed our ‘hunger hormone’. This, in turn, increases our desire to seek out food.  

Other animal model evidence suggests that THC activates receptors in the olfactory bulb – the brain’s smell centre. This enhances the smell and taste of food which, naturally, increases how much we want to eat.

It is also believed that cannabis interacts with dopamine, the neurotransmitter involved in signalling pleasure. By increasing the release of dopamine, THC increases the sensation of pleasure when eating sugary foods which, you guessed it, makes us want more. 

Busting the ‘lazy stoner’ stereotype

The term ‘stoner’ – someone who is habitually high on cannabis – often conjures up a very specific stereotypical image: an unproductive, couch-bound, zombie-like individual with a bong in their hand who spends their day devouring food in a haze of smoke. Because of this, there is often an expectation that those who frequently indulge in cannabis will put on more weight. 

The ‘lazy stoner’ stereotype is outdated. It was formulated on misinformation, stigma, and is rooted in fatphobia. As modern attitudes towards cannabis use are changing, it is becoming increasingly clear that cannabis does not make you lazy.  

In fact, studies show that cannabis users actually engage in more physical activity than non-users. Why is this the case? It could be because cannabis relieves pain, making exercise easier for those who may previously not have been able to. Alternatively, cannabis may induce a behavioural change that makes it more enjoyable to work out. Researchers don’t know the answer, but even world-famous athletes claim cannabis to be their key to sporting success.

The relationship between cannabis and metabolism is far more complex than previously credited. Research indicates that frequent cannabis use isn’t actually associated with weight gain at all – has the munchies myth been debunked?

The link between cannabis and body weight

Scientists investigating the link between cannabis and obesity have found no evidence to support the claim that consuming weed will cause weight gain. Research actually shows that cannabis consumers are less likely to be overweight. 

One study, published in the American Journal of Epidemiology in 2011, found that cannabis users had lower obesity rates than non-users. Amongst 50,736 survey respondents, 16% of cannabis users were classified as obese on the BMI scale, compared to 22% of non-users.

A 2019 study published in the International Journal of Epidemiology showed that only 15% of cannabis users were considered to be obese, compared to 20% of non-users. Over the 3-year time period that the study took place, cannabis users actually put on less weight than non-users. Granted, the differences were subtle – only 2 pounds, on average – but these findings were surprising because of the well-known munchies effect.

A 2024 study, published in the journal Cannabis and Cannabinoid Research, analysed US cannabis consumers over six years and showed that cannabis users had a lower prevalence of obesity and generally lower body mass index (BMI) than non-users.

The data suggests that there is a correlation between cannabis use and lower weight, but that doesn’t mean that weed is the next wonder weight loss drug. While science doesn’t have a definitive answer as to why cannabis consumers are less likely to be overweight, there are some exciting theories.

Why cannabis consumers might weigh less

Research suggests cannabis consumption may increase metabolism, meaning your body uses energy faster. One theory is that THC, over time, can downregulate CB1 receptors, which “reduces energy storage and increases metabolic rates”, according to the authors of a study published in Cannabis and Cannabinoid Research in 2018. This may reverse the effect of increased omega-6/omega-3 ratios, which are known to contribute to obesity through endocannabinoid activity. In simple terms, the study proposes that frequent cannabis users, despite having a greater caloric intake, have ‘faster’ metabolisms and, thus, lower BMI.

Another theory is that cannabidiol (CBD), the major non-psychoactive cannabinoid in cannabis, may aid in weight loss. Several experimental studies have shown that CBD can suppress appetite and promote the ‘browning’ of fat cells – turning white, stored fat into brown, energy-burning fat.

Other theories suggest that it is the knock-on effects of cannabis that lead to consumers being less likely to be overweight. We know that cannabis consumers are more likely to be active, not lazy. Research shows that cannabis can also reduce anxiety and improve sleep, thus lowering the likelihood of overeating to combat stress or fatigue. 

Terpenes and cannabinoids that aid weight loss

Cannabis is more than just THC and CBD – the average plant contains hundreds of other cannabinoids and terpenes that have significant therapeutic properties.

Terpenes are the compounds that give cannabis and other plants their unique smell and flavour, and many of them have been proven to influence weight, appetite and metabolism.

Limonene

Limonene, a terpene found in citrus fruits and cannabis strains with a ‘lemony’ smell has been shown to boost metabolism and may support fat oxidation. Studies also show that limonene can improve mood and reduce stress, leading to less ‘emotional eating’.

Humulene

Humulene is a terpene found in hops, sage and cannabis. While researchers are still trying to understand exactly how this terpene interacts with the body, humulene may help with weight management by suppressing appetite.

β-caryophyllene

β-caryophyllene is a terpene that produces a spicy smell. It is found in pepper, cloves, and many strains of cannabis. In one study, β-caryophyllene was shown to improve several indicators of metabolic health in obese mice.

THCV

Several studies have shown that the cannabinoid tetrahydrocannabivarin (THCV) suppresses appetite. Sometimes called ‘diet weed,’ THCV has fewer psychoactive effects than THC. Research has shown that it can reduce appetite, increase satiety, and increase energy metabolism. More studies are needed in humans to establish exactly how THCV could be useful for weight loss and managing obesity, yet evidence suggests that strains rich in THCV, such as Durban Poison, may help consumers regulate weight more effectively.

Is cannabis a weight loss drug?

While there is a compelling amount of evidence that cannabis can have a positive impact on controlling weight gain, it’s clear that cannabis is not a weight loss drug. Association is not causation; meaning, these findings don’t address the question of whether cannabis directly causes our weight to change. 

Studies that show cannabis is related to differences in weight could be due to behavioural changes. For example, cannabis users may consciously adjust their diet to offset the caloric intake from the munchies or may feel more compelled to increase their physical activity. 

Still, the anecdotal and scientific evidence connecting cannabis and weight loss is exciting – conscious cannabis consumption can play an important role in maintaining a healthy waistline. There is no magic bullet to weight loss. Healthy eating, regular exercise, and quality of sleep remain the key to keeping weight under control. While cannabis alone isn’t a weight loss drug, it can play an important role in living a healthy life.