It seems to lessen side effects from treating hepatitis C and increase treatment effectiveness.
Treatment for hepatitis C infection is harsh: negative side effects include fatigue, nausea, muscle aches, loss of appetite, and depression. Those side effects can last for months, and lead many people to stop their treatment course early.
But a 2006 study in the European Journal of Gastroenterology and Hepatology found that 86% of patients using marijuana successfully completed their Hep C therapy. Only 29% of non-smokers completed their treatment, possibly because the marijuana helps lessen the treatment's side effects.
Marijuana also seems to improve the treatment's effectiveness: 54% of hep C patients smoking marijuana got their viral levels low and kept them low, in comparison to only 8% of nonsmokers.
Marijuana may help with inflammatory bowel diseases.
Patients with inflammatory bowel diseases like Crohn's disease and ulcerative colitis could benefit from marijuana use, studies suggest.
University of Nottingham researchers found in 2010 that chemicals in marijuana, including THC and cannabidiol, interact with cells in the body that play an important role in gut function and immune responses. The study was published in the Journal of Pharmacology and Experimental Therapeutics.
The body makes THC-like compounds that increase the permeability of the intestines, allowing bacteria in. But the cannabinoids in marijuana block these compounds, making the intestinal cells bond together tighter and become less permeable.
But the National Academies report said there isn't enough evidence to be sure whether marijuana really helps with these conditions, so more research is needed.
It relieves arthritis discomfort.
Marijuana alleviates pain, reduces inflammation, and promotes sleep, which may help relieve pain and discomfort for people with rheumatoid arthritis, researchers announced in 2011.
Researchers from rheumatology units at several hospitals gave their patients Sativex, a cannabinoid-based pain-relieving medicine. After a two-week period, people on Sativex had a significant reduction in pain and improved sleep quality compared to placebo users.
Other studies have found that plant-derived cannabinoids and inhaled marijuana can decrease arthritis pain, according to the National Academies report.
Marijuana users tend to be less obese and have a better response to eating sugar.
A study published in the American Journal Of Medicine suggested that pot smokers are skinnier than the average person and have healthier metabolism and reaction to sugars, even though they do end up eating more calories.
The study analyzed data from more than 4,500 adult Americans — 579 of whom were current marijuana smokers, meaning they had smoked in the last month. About 2,000 people had used marijuana in the past, while another 2,000 had never used the drug.
The researchers studied how the participants' bodies responded to eating sugars. They measured blood-sugar levels and the hormone insulin after participants hadn't eaten in nine hours, and after they'd eaten sugar.
Not only were pot users thinner, their bodies also had a healthier response to sugar. Of course, the study couldn't determine whether the marijuana users were like this to begin with or if these characteristics were somehow related to their smoking.
While not really a health or medical benefit, marijuana could spur creativity.
Contrary to stoner stereotypes, marijuana usage has actually been shown to have some positive mental effects, particularly in terms of increasing creativity, at least in some contexts. Even though people's short-term memories tend to function worse when they're high, they actually get better at tests requiring them to come up with new ideas.
Researchers have also found that some study participants improve their "verbal fluency," their ability to come up with different words, while using marijuana.
Part of this increased creative ability may come from the release of dopamine in the brain, which lowers inhibitions and allows people to feel more relaxed, giving the brain the ability to perceive things differently.