Herbs, supplements and HIV

January 2005     View PDF     En español

Selenium and HIV

Controversy remains over using selenium in people with HIV. Selenium is a toxic substance that gets spread into the environment through the burning of fossil fuel and other industrial processes. Trace amounts of it is often found in drinking water. Symptoms from consuming too much selenium include brittleness and loss of hair and nails, skin redness, blisters, vomiting, fatigue, neurological defects and damage to the liver and spleen.

Trace amounts of selenium are in the foods we eat. At these low levels, selenium is essential for proper immune function. The U.S. Recommended Daily Allowance of selenium (all ages and genders) is 55 micrograms (µg). Levels are slightly higher for pregnant (60µg) and lactating (70µg) women. The Institute of Medicine has proposed that the maximum daily intake before causing toxic effects is roughly 400µg for adults.

Selenium deficiencies are rarely seen in the U.S., though they have been seen among people on Total Parental Nutrition (TPN), or intravenous nutrition. TPN is sometimes used to treat wasting syndrome in people with HIV. It is standard practice for doctors to check selenium levels in people on TPN and supplement as necessary.

Selenium toxicity has been seen in people using selenium supplements. In one case, high levels led to selenium poisoning in a man using supplements as a way to manage his fatigue. Investigators analyzed the over-the-counter product and found selenium levels of 500 to 1,000 times the amount labeled for each pill. This led to warnings noting that unusual diets and vitamin supplements are the most common causes of selenium toxicity in the U.S.

Several studies suggest that low levels of selenium are related to HIV disease progression. One study of 24 children and another of 125 adults has shown that those with these deficiencies were at a greater risk for disease progression and death. However, it’s unknown whether or not selenium supplements would make a difference.

Other studies suggest that HIV needs selenium in order to reproduce. Some have proposed that when HIV uses all the selenium in a given cell, it may leave that cell to find more selenium by infecting other cells. Interestingly, HIV-positive women with low selenium levels have higher rates of HIV in vaginal secretions. Again, it remains unclear if selenium deficiency is a cause or an effect of HIV disease progression and if supplements will help or hurt.

A study conducted at the University of Miami compared selenium supplements (200µg/day) to placebo in 259 people living with HIV (147 men, 112 women). Information about CD4+ cell count, viral load and other parameters were collected at the first study visit and then every six months thereafter for two years.

One component of the study was to evaluate the frequency of hospitalizations among those receiving selenium compared to placebo. Unfortunately, sloppy data reporting leaves results of this aspect of the study completely not interpretable currently.

Additionally, researchers examined blood levels of selenium in 112 HIV-positive women on anti-HIV therapy. They looked for links between selenium levels and the risk for pre-cancerous cervical cells (cervical dysplasia). While selenium levels were lower in women who developed dysplasia, using supplements made no difference in the risk of developing dysplasia. Five women who used selenium supplements and seven on placebo developed dysplasia.

In short, the most that can be concluded from these reports is that it remains entirely unknown if selenium supplements offer any benefit or harm, whatsoever. Risks for cervical dysplasia appear slightly higher when selenium levels are lower, but selenium supplements do not appear to eliminate this risk. This sloppy data reporting is a tragedy. Well-designed research is critical to evaluating the possible benefits (and risks) of selenium supplements.