Researchers from Michigan State University found that marijuana users with HIV have fewer inflammatory white blood cells. As the immune system continuously tries to fight the virus, inflammation in the brain occurs in many HIV patients. However, the study's authors report that those who use marijuana note levels of inflammatory cells that are more in keeping with those of healthy individuals who do not have the infection. This means that marijuana could help HIV patients to hold on to their cognitive function for a longer time.

It is estimated that one out of every seven of the 1.1 million people infected with HIV in America is not aware that they are carrying the virus. In Europe, meanwhile, experts report infections with the virus are growing at an "alarming" rate, with 160,000 people contracting HIV across 53 European countries in 2016 alone, according to the World Health Organization. This is a 52 percent rise from 2007's figures.