The randomized, placebo-controlled, double-blind trial was performed by scientists from Miami University in Florida, and led by Dr Barry E. Hurwitz.
The results of the trial were published in yesterday's edition of the Archives of Internal Medicine.
In the trial 262 male and female patients with HIV were randomly assigned to take a prescription of either 200 micrograms of selenium supplements (as a high-yield yeast formulation) or a placebo every day. Their blood serum was then monitored for 9 months for level of selenium, HIV viral load (the extent to which the virus had replicated), and their CD4 T-cell count (an indication of how healthy their immune system was).
174 patients completed the 9 month programme. Of these, the ones who took the selenium supplements every day, compared to the placebo group, experienced a reduced HIV viral load, and an increase in their CD4 T-Cell count. The placebo group experienced an increase in their HIV viral load and a decrease in their CD4 T-cell count.
The findings were still significant after taking into account other demographic, ethnic, socio-economic, and health factors such as past drug use, time since HIV diagnosis, adherence to antiretroviral medication and infection with hepatitis C.
The scientists also found that patients who did not stick to the daily regime of selenium supplements had a lower level of selenium in their blood, and when this fell below 26.1 micrograms per litre this correlated with increased HIV viral load and decreased CD4 T-cell count.
The scientists concluded that a daily supplement of selenium can "suppress the progression of HIV-1 viral burden and provide indirect improvement of CD4 count." They suggest that these results "support the use of Selenium as a simple, inexpensive, and safe adjunct therapy in HIV spectrum disease."
Previous research has suggested that selenium plays a role in keeping the immune system healthy, and that HIV patients tend to show a depletion in the trace element. However, the impact of selenium supplements on HIV patients had not yet been studied in a controlled trial.
Selenium is a non metal similar to sulphur in its chemical properties. In large amounts it is toxic, but in trace amounts it enables organisms to produce enzymes that help cells to function.
Selenosis is a serious disease caused by taking too much selenium. The upper tolerance level in humans is about 400 micrograms a day. Selenosis causes stomach problems, loss of hair and nails, liver and brain damage. It can be fatal.
"Suppression of Human Immunodeficiency Virus Type 1 Viral Load With Selenium Supplementation."
Barry E. Hurwitz; Johanna R. Klaus; Maria M. Llabre; Alex Gonzalez; Peter J. Lawrence; Kevin J. Maher; Jeffrey M. Greeson; Marianna K. Baum; Gail Shor- Posner; Jay S. Skyler; Neil Schneiderman.
Arch Intern Med. 2007;167:148-154.