People who adhere closely to a Mediterranean diet—comprised of olive oil, grains, fruits, nuts, vegetables and fish, and low in meats and dairy—may have a much lower risk of developing diabetes, according to the authors of a study published online in the British Medical Journal and reported by the New York Times. The study focused exclusively on HIV-negative patients but could have implications for people with HIV.

Some studies have found an increased risk for insulin resistance in people living with HIV who take certain antiretroviral (ARV) drugs. This condition, where the hormone insulin is less effective at controlling blood sugar, can be a precursor to the development of diabetes. Simple and cost effective methods to reduce a person’s risk for developing diabetes, such as the so-called Mediterranean diet, could be beneficial for people with HIV who have insulin resistance.

Migel Martínez-González, MD, from the University of Navarra in Pamplona, Spain, and his colleagues enrolled 13,380 Spanish university graduates who did not have diabetes and followed them for an average of four and a half years. The study participants filled out regular surveys about their diet and lifestyle, and were scored based on how closely their diets matched a classic Mediterranean diet. Those with a score of 7 or more ate food that most resembled a Mediterranean diet, while those with a score of 3 or less ate food that was the most different from a Mediterranean diet—typically high in meat and dairy and low in fruits, vegetables and healthy fats like olive oil.

Martínez-González’s group found that those with a high score were 83 percent less likely to develop diabetes than those with a low score. While the authors acknowledge that self-reported surveys are not the most rigorous measure of a person’s actual diet, they say that the size of the study does lend strength to its finding.