Study: Pot Use Linked With Lower Risk of Liver Disease

Consuming alcohol is a well-known cause of liver damage, but the opposite may hold true for smoking pot.

That is the takeaway of new research published late last month in PLOS One. 

After examining a “nationally representative” sample of Americans, the researchers said that they found that “current marijuana use is inversely associated with steatosis,” or a condition that arises from too much fat in the liver. 

“The pathophysiology is unclear and needs further study. No significant association was established between marijuana use and liver fibrosis, irrespective of past or current use,” they wrote.

The study, conducted by a group of Chinese researchers, “aimed to assess the association between marijuana use and liver steatosis and fibrosis in the general United States population utilizing data from the National Health and Nutrition Examination Survey (NHANES).” 

“This cross-sectional study was performed with data from the 2017–2018 cycle of NHANES. The target population comprised adults in the NHANES database with reliable vibration controlled transient elastography (VCTE) results,” the authors of the study wrote in their explanation of the methods. “The median values of the controlled attenuation parameter (CAP) and liver stiffness measurement (LSM) were used to evaluate liver steatosis and fibrosis, respectively. After adjusting for relevant confounders, a logistic regression analysis was used to assess the association between marijuana use and liver steatosis and fibrosis.”

The researchers analyzed a pool of 2,622 participants.

“The proportions of never marijuana users, past users, and current users were 45.9%, 35.0%, and 19.1%, respectively. Compared to never marijuana users, past and current users had a lower prevalence of liver steatosis (P = 0.184 and P = 0.048, respectively),” they wrote. “In the alcohol intake-adjusted model, current marijuana use was an independent predictor of a low prevalence of liver steatosis in people with non-heavy alcohol intake. The association between marijuana use and liver fibrosis was not significant in univariate and multivariate regression.”

Also known as “fatty liver disease,” steatosis “affects one in three adults and one in 10 children in the United States,” according to the Cleveland Clinic. 

“There’s no medication specifically for fatty liver disease. Instead, doctors focus on helping you manage factors that contribute to the condition. They also recommend making lifestyle changes that can significantly improve your health,” the Cleveland Clinic says.

Despite the intriguing findings of the study, the Chinese researchers urged caution.

“Nevertheless, the present study has several limitations. First, this was an observational study; no causal inference can be made, and correlations should be interpreted as associations. Second, marijuana use was based on self-reporting, and the skewness of the distribution of the number of marijuana use may be subject to misclassification, limiting the power of our secondary analysis with the days of cannabis usage,” they wrote. 

“Such inaccurate reports may introduce a bias towards the null hypothesis for the result. Third, physical activity and diet were not included in the analyses. Furthermore, due to the limitation of the NHANES database, we could not rule out biliary cirrhosis and primary liver diseases such as Wilson’s disease and the use of steatogenic medication. Also, we could not evaluate the type of marijuana and the dose-response correlation between marijuana use vs. the prevalence of liver steatosis and fibrosis.”

They added: “In conclusion, we found that current marijuana use is inversely associated with liver steatosis. Further studies are required to confirm these results longitudinally, and investigations into marijuana compounds and their biological effects are promising for treating and preventing fatty liver disease.”