According to a study, smoking weed everyday leads to lower body fat percentage

A new study proposes that people who smoke marijuana daily have a lower percentage of body fat. The study observed a sample of adults 18-26 years old and observed them again six years later. In these observations, the researchers measured BMIs and amount of marijuana used. The study concludes women who smoked marijuana everyday had a 3.1% lower BMI and men who smoked everyday had a 2.7% lower BMI in contrast to those who did not smoke everyday.

Does daily marijuana use help weight loss?

Does daily marijuana use help weight loss?

In class we learned that correlation is not causation. Just because the study shows a correlation between smoking marijuana everyday and a lower body fat percentage- does not mean that they are related. The study does not cite any mechanism that result in marijuana causing a lower body fat percentage. However, the study does control for confounding/third variables that would effect the correlation. According to the study, they controlled for diet, exercise, and alcohol drinking habits.

The study took place over a period of time, six years. As we learned in class this helps reduce the factor of random chance in the study. However, since the study was observational random chance cannot be entirely ruled out. Also, the study shows correlation between daily marijuana smoking and lower BMI’s but this can be explained different ways. Direct causality, a person smokes marijuana everyday this then causes them to have a lower BMI. Reverse causality, there is something about have a lower BMI that causes a person to smoke marijuana everyday. Confounding or third variables, smoking marijuana daily and lower BMI are not causally related but effected by something else. For example income: a person smokes a lot of marijuana this then causes them to have little extra money which in turns causes them to eat less and have a lower BMI. Another scenario is socioeconomic factor:  people from lower income areas have lower BMIs as they have less food because lower income areas are more at risk for gang activity they have a larger likeliness of being exposed to marijuana and smoking everyday. Another third/confounding variable is culture: people who grow up in a hippie lifestyle home are more likely to smoke as it is apart of the culture, they are also more likely to have lower BMI’s because they are more likely to be vegetarians as both are norms of the culture. Since there is no mechanism found in the study- any of these correlations could be feasible to explain the relationship between lower BMIs and smoking marijuana daily.

Does smoking marijuana daily lead to weight loss?

Does smoking marijuana daily lead to weight loss?

This study involved a lot of the concepts that we have spoken about in class. It was a longitudinal study. We talked about how this reduces random chance- but does not rule it out. The study’s outcome shows a link between marijuana and BMI but there is not evidence for a mechanism that would explain how marijuana effects BMI therefor we cannot be sure it is marijuana causing the lower BMI, the lower BMI causing daily marijuana smoking, or another confounding variable causing both. The study controlled for factors that may effect the outcome- this increases validity of the results. However, because this is a correlation (as we learned in class) there are still options for reverse causality and random chance to explain why there is a link. Overall, I would not recommend smoking marijuana everyday as a weight loss tactic as there is not found mechanism.

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9 thoughts on “According to a study, smoking weed everyday leads to lower body fat percentage

  1. Matthew Jacobs-Womer

    Well I have heard of athletes using marijuana to put on weight, but never as it being a way to cut weight. Since this relates to BMI, I would be interested to actual see the final physique of the participants: lower BMI does not necessarily mean better shape. I appreciate the approach you took at the article you found, you were very skeptical and took a logical approach. There may be some legitimacy to frequent marijuana use lowering one’s BMI rate, but without an actual mechanism it seems to be a stretch. Not only is it a stretch but it is also only by a difference of 2%. In my opinion, there seems to be no logical reason for someone to actually smoke marijuana everyday to loose weight. Doing that will have consequences on you lungs and you could much more easily do some exercise. The combination of marijuana and physical activity has seemed to be frequently coming up, I found this article about how a gym is going to allow members to consume and smoke marijuana products while lifting.

  2. Daniele Patrice Loney

    I really enjoyed how you related this blog post so much to everything we have talked about in class. Very well written! As i read the first paragraph i kept thinking to myself that i was going to comment on the fact that correlation does not equal causation and that they didn’t provide a mechanism to explain the relationship they were studying– but you took the words right out of my mouth!! very well said 🙂
    If i were to make a hypothesis, I would bet on the fact that the lower BMI is not directly related to daily marijuana use, but rather that they are both causes by a third variable, which in my opinion would most likely have to do with lifestyle choices. An interesting way to expand on the study you mentioned would be to NOT measure any confounding variables, and then compare those results to the results of the initial study. Who knows! Maybe that would help point us in the right direction of finding a mechanism to explain this correlation 🙂
    Thanks,
    Daniele

  3. Lucas Thomas Hansen

    The title of this blog really caught my attention, since many people I know of that smoke pot religiously are skinny. Honestly though i had no idea that there was an actual science behind this idea and that it actually would decreases BMI. Another article i food stated that research found that people who smoke pot tend to have better cholesterol than non users. http://jezebel.com/smoke-weed-and-be-skinny-the-stoner-diet-plan-506922139

  4. Joe Garrett

    The title of this post grabbed my attention because I would think that people who smoke weed everyday would eat more food due to having the munchies everyday, like Christopher stated in the first comment. I thought this post was well written and applies Andrew’s methodology very well. I think another possible variable for causing this would be that people who smoke cannabis everyday are less likely to drink alcohol which would cause them to gain less weight than those who choose alcohol over cannabis.

  5. sbh5327

    I too have heard the hypothesis that smoking marijuana leads to weight loss. I also have learned that it greatly depends on the strain of cannabis that is smoked. Some strains do cause the “munchies” and can lead to weight gain while others are in fact predicted to result in weight loss. I also thought your provided a very strong z variable. The idea that marijuana and weight loss can both be due to income was a good suggestion.

  6. Erin Nicole Kemp

    This post is very well thought out and applies what Andrew taught us. My only question is what do you or the study mean by a hippie lifestyle? Also, it is interesting to me that marijuana use is higher in lower socioeconomic areas. I would assume middle and high class neighborhoods have just as much or more marijuana use than poor neighborhoods so that statistic is surprising and makes me question some of the data gathering of the study.

  7. Nathan O'brien

    I’m not entirely sure why, but I am not too surprised to hear that people who smoke weed every day have a lower BMI. I see that you mentioned a socioeconomic factor that poorer people tend to be less overweight. I actually feel as though, the less money people have the more likely they will be obese. This might sound weird at first, but just think about it. If you have very little money, you are not going to buy an expensive salad, you might instead go to McDonald’s because it is much cheaper, more filling, and probably closer to you. http://www.livescience.com/28644-obesity-rates-cities-income.html
    I feel like the marijuana itself is not causing a lower BMI, but maybe the actions that you take or the decisions that you make will cause a lower BMI. I also read this study that says that people who smoke weed have better insulin levels, which in turn might be a cuase for having a lower BMI. http://www.care2.com/greenliving/does-marijuana-make-you-thin.html

  8. Natalie Elizabeth Burns

    I think post was very well written and interesting. I liked how you brought what we learned in class and applied it in this situation. I agree with another one of the comments that talks about the idea of the munchies when smoking. Although, this is a very proven point, I think that there could be a correlation between the lower BMI and smoking weed. Because, after all it is “grass” and we were always taught that green things are healthy for you. Good post!

  9. Christopher Ronkainen

    I found this post very intriguing. Who would have known that people who smoke marijuana have a lower BMI on average? I think i found this post so interesting because when I first saw the title I thought it was ridiculous. I mean everyone that smokes weed gets the munchies and has food cravings for extremely unhealthy food, right? I found an interesting Smithsonian article that talks about talks about how THC increases our appetite by increasing our sense of smell when it comes to food. I think you would be interested in checking it out!

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