Smoking marijuana is perhaps not a lifestyle habit that many would classify as ‘healthy’. However, a study published this week in the American Journal of Medicine discovered that pot-smoking is associated with improvement in a range of health markers including lowered waist circumference, body mass index and fasting insulin levels, as well as improved blood sugar control and insulin sensitivity [1]. After taking into account a range of potential ‘confounding factors’ such as age, physical activity and smoking, marijuana use was still found to be associated with improvement in measures of fasting insulin, insulin sensitivity, ‘healthy’ HDL-cholesterol and waist circumference.
This sort of ‘epidemiological’ study cannot, however, prove that cannabis use brings these benefits for health, and only tell us that it’s associated with these benefits. At first sight, the findings actually appear to fly in the face of common sense. As the authors point out, marijuana users tend to consume more calories than non-users. The authors also refer to an increase in ‘acute intake’ with marijuana use (meaning that using marijuana can cause people to eat or drink more shortly after). Back in the day, we referred to this ‘increase in acute intake’ as ‘the munchies’.
I can certainly bear personal testament to this phenomenon. I still have vivid recollections of smoking pot in a former life (well, I was at medical school for 6 years) and the effect this had on me. After initially feeling ‘bombed out’, I would find something hilariously funny (that, in the cold light of day could only really be viewed as mildly amusing). Shortly after, I’d be driven to consume industrial quantities of, say, chocolate Hob Nobs (a type of biscuit/cookie) and tinned custard. How, on heaven’s earth could carb- and calorie-fest which invariably came as part and parcel of dope-smoking possibly lead to lower weight, reduced waist circumference and improved markers for diabetes, one might ask?
The authors of this research suggest some mechanisms that have to do with substances (such as cannabidiol) which bind to ‘cannabinoid’ receptors in the brain and may influence physiological factors. It’s been found, for instance, that mice genetically bred to lack one of the two main cannabinoid receptors (receptor number 1) are resistant to weight gain, suggesting a role for this receptor in obesity. Cannabidiol partially blocks cannabinoid receptors which might have some role in any weight reducing effect marijuana has. Adding strength to this idea is the findings of research which finds that giving cannabidiol to mice induces weight loss [2]. Also, giving cannabis to obese rats has been shown to have the same effect [3].
Unless these studies are replicated in humans, then we’re still in the dark about the effect cannabis has on weight and associated aspects of health. And, of course, there’s always the possibility that even if beneficial from these perspectives, cannabis may have the potential for harm too. Notably, there is some thought that cannabis has some ability to trigger psychotic illness.
However, there exists evidence that cannabis (and in particular cannabinoid substances found in it) offers the potential of doing more good than harm. Here’s an extract from a summary of an article about the impact of cannabinoids on health [4]:
Despite the mild addiction to cannabis and the possible enhancement of addiction to other substances of abuse, when combined with cannabis, the therapeutic value of cannabinoids is too high to be put aside. Numerous diseases, such as anorexia, emesis, pain, inflammation, multiple sclerosis, neurodegenerative disorders (Parkinson’s disease, Huntington’s disease, Tourette’s syndrome, Alzheimer’s disease), epilepsy, glaucoma, osteoporosis, schizophrenia, cardiovascular disorders, cancer, obesity, and metabolic syndrome-related disorders, to name just a few, are being treated or have the potential to be treated by cannabinoid agonists/antagonists/cannabinoid-related compounds. In view of the very low toxicity and the generally benign side effects of this group of compounds, neglecting or denying their clinical potential is unacceptable…
In a way, one might possibly think of cannabis or cannabinoids in a way similar to our general attitude to licenced ‘drugs’ or other conventional therapies (such as surgery): these invariably pose risks, but have considerable benefits to offer too.
References:
1. Penner EA, et al. The Impact of Marijuana Use on Glucose, Insulin, and Insulin Resistance among US Adults. Am J Med [epub 16 May 2013]
2. Weiss L, et al. Cannabidiol lowers incidence of diabetes in non-obese diabetic mice. Autoimmunity. 2006;39:143–151
3. Levendal R, et al. Cannabis exposure associated with weight reduction and β-cell protection in an obese rat model. Phytomedicine. 2012;19:575–582
4. Kogan NM, et al. Cannabinoids in health and disease. Dialogues Clin Neurosci. 2007;9(4):413-30