Decoding Cannabis: Is “skinny weed” real? The science behind THCV and weight loss explained

This week, we are actually looking at two adjacent papers, both from 2025, focusing on the cannabinoid THCV, and the online buzz around it being “skinny weed”. THCV has picked up the nickname because, unlike THC, which is famous for triggering the munchies, it appears to actually push appetite in the opposite direction.

The first piece of research is a small (but still very useful) human trial testing THCV strips for weight loss over 90 days. The second is a review that pulls together how THCV works across the body. Read together, they tell quite a promising story, though one with a few caveats worth explaining.

What is THCV, and why is it called "skinny weed"?

THCV, short for tetrahydrocannabivarin, is a cannabinoid found in some (but not all) cannabis strains, though usually only in trace amounts. It is closely related to THC but behaves very differently in the body, and at the doses you will find in most cultivars, it does not get you high.

The key difference comes down to how it interacts with one of the two endocannabinoid receptors.

While THC switches on the CB1 receptor, which results in increased feelings of hunger, THCV seems to do the exact opposite - at least at low doses (more on this a bit further down). Rather than activating CB1, it blocks it, which is why researchers have repeatedly linked THCV to reduced appetite. It also partially activates the second receptor, CB2, which helps regulate inflammation and blood sugar.

If you want a refresher on how these two receptors actually work, our guide to the endocannabinoid system breaks it all down

That combo, dialling CB1 down while nudging up CB2, is what makes THCV’s metabolic profile so interesting, and why it keeps turning up in obesity and diabetes research.

But what does the evidence actually say?

The first piece of research we are going to unpack today is a review published in AIMS Neuroscience, which gathers up the preclinical and early human research on how THCV affects appetite, weight, and blood sugar control in conditions like obesity and type 2 diabetes. The second is a placebo-controlled trial in the journal Cannabis, which tested THCV and CBD oral strips for weight loss in 44 adults over 90 days.

All bases covered, preclinical and human trials.

Does the data actually show THCV helps with weight loss?

While there were only 44 participants and the trial ran for only three months, the data gathered, and the outcomes are really quite encouraging. 

Researchers gave the participants one of three options each day for the duration of the trial:

• A lower-dose strip: 8mg of THCV combined with 10mg of CBD 

• A higher-dose strip: 16mg of THCV combined with 20mg of CBD

• A placebo strip: no active cannabinoids

These are the type of strips that dissolve away on the tongue almost as soon as they touch it, releasing the cannabinoids straight into the mouth’s lining rather than sending them through the gut. Participants took theirs once a day on an empty stomach, with no other changes to their diet or exercise routines.

And the results?

As we said, the results were really promising, and lined up neatly with what the mechanism behind THCV predicts: 

• The higher dose group (16mg THCV / 20mg CBD) lost an average of 4.1 kg

• The lower-dose group (8mg THCV / 10mg CBD) lost an average of 2.6 kg

• The placebo group stayed at almost the exact same weight, losing just 0.1 kg

Weight was not the only thing that moved. 

Compared with placebo, the people using the strips also recorded significant reductions in waist size, blood pressure and both total and LDL cholesterol, the “bad” cholesterol linked to heart disease. For a single 90-day intervention, that is a clean sweep across the metabolic markers that tend to travel together, and it fits the wider picture of THCV steering the body away from fat storage.

How does THCV actually work on appetite and blood sugar?

The strip trial shows that THCV may be a genuine option for those looking to lose weight, but it's the review where the data broadens out from weight loss into metabolism more generally.

The appetite and fat-burning side

By blocking that CB1 receptor rather than switching it on, THCV appears to turn down the hunger signal that THC can send into overdrive.

In animal studies pulled together by the review, this translated into real effects: rodents given THCV ate less, and some showed a marked jump in energy expenditure, meaning they burned more of what they took in. THCV also reduced fat building up in the liver, a problem closely tied to obesity and metabolic disease.

It’s not just animals that the review looked at, though. In a human brain-imaging study, a single dose of THCV changed how volunteers’ brains responded to images of food, dialling up the response to unappetising food and shifting activity in the brain’s reward circuitry. In other words, THCV may not just reduce your appetite, it may also alter how rewarding food feels in the first place.

The blood sugar side

This is where THCV’s metabolic case gets stronger because the best human evidence so far is not about weight at all, but also how it affects blood sugar levels. 

In a 2016 randomised controlled trial of THCV in people with type 2 diabetes included in the review, 62 patients took either THCV, a comparison treatment, or placebo over 13 weeks. The THCV group showed significantly lower fasting blood glucose levels and improved pancreatic cell functioning (the cells that produce insulin), with zero side effects. 

One caveat to point out: the diabetes trial found no meaningful weight loss, even though it improved blood sugar. The strips trial found clear weight loss. Rather than cancelling out, the two point to something useful: THCV seems to act across several metabolic levers at once, and which effects show up most strongly may depend on the dose, the formulation, and who is taking it.

Are medical cannabis cultivars with decent levels of THCV available to UK patients?

Not yet, but they (potentially) soon will be. 

Glass Pharms, the first company licensed to grow commercial medical cannabis in the UK, has been working on breeding a medical cannabis strain with high levels of THCV, which will hopefully come to market sometime in the next few months. It is a promising sign of where domestic cultivation is heading.

For now, the options remain limited, and anything sold online as “skinny weed” sits outside the regulated legal system entirely. 

When a THCV-rich medical cannabis product does become available, we expect Releaf patients to be among the first in the UK to have access to it, thanks to our ongoing partnership with Glass Pharms.

Want to learn more? Head to our fast (and totally cost-free) medical cannabis eligibility checker. It takes all of 30 seconds to complete, and could be your first step towards better health.

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