Contrary to popular belief, HIV-positive people gain excess body fat because of the virus itself rather than antiretroviral (ARV) treatment, according to a recent study. Researchers looked at 328 people first starting ARVs and found that limb, trunk and visceral abdominal fat jumped a respective 15 percent, 22 percent and 31 percent after just two years of treatment. Lean muscle mass rose only about 1 or 2 percent.

The investigators found a strong connection between participants’ viral loads at the beginning of the study and how much fat they put on. Those with a viral load greater than 100,000 at the outset had average increases of 25 to 35 percent in subcutaneous and visceral abdominal fat. Those starting with a viral load below that point typically saw average fat gains of 10 percent or less.

Grace A. McComsey, MD, a professor of medicine and pediatrics at Case Western Reserve University in Cleveland, Ohio, who was the study’s lead author, says that while she’s very confident in her “alarming” findings, more research is certainly needed.

She believes that the medical field has let its guard down with regard to body fat issues, now that the age of facial wasting and other major lipodystrophy side effects has faded thanks to improvements in ARVs.

Cautioning that such fat gains may raise the risk of diabetes and heart disease, McComsey strongly advocates that HIV-positive people eat a healthy diet and get plenty of exercise to combat such outcomes.