A study of HIV-infected African women found that daily doses of multivitamins appear to slow down the disease and cut the risk of developing AIDS in half.

The researchers who conducted the study in Tanzania (search) suggested that vitamin supplements could be used in developing countries to delay the need for AIDS drugs, saving them for use at more advanced stages and avoiding their side effects.

"It's a low-cost intervention that could result in major savings and be helpful to many individuals in terms of better quality of life," said Dr. Wafaie Fawzi of Harvard School of Public Health (search), who led the study reported in Thursday's New England Journal of Medicine.

The results in Africa probably cannot be duplicated in the United States, where people already take vitamins and nutritional deficiencies are less common, he said.

Fawzi stressed that the vitamins are not a substitute for powerful AIDS drugs, which are used once an HIV infection reaches later stages. Until recently, AIDS drugs were not available to most people in Tanzania, and they were not available when the study was done, he said.

So the researchers at Harvard and in Tanzania set out in 1995 to determine whether vitamins would benefit a group of HIV-infected pregnant women. The 1,078 women received either a multivitamin, a multivitamin with vitamin A, vitamin A alone or a dummy pill.

The women were followed for about six years. Eighteen of the 271 women who took multivitamins, or 7 percent, developed AIDS, compared with 31 of the 267 women, or 12 percent, who took a dummy pill. Nineteen percent in the multivitamin group and 25 percent in the comparison group died, but the difference was not statistically significant.

The women on multivitamins (search) also had fewer late-stage complications such as fatigue, diarrhea and mouth ulcers and lower levels of the virus in their blood.

Besides boosting the immune system, multivitamins may also hinder the virus' ability to make copies of itself, the researchers said.

They found no significant benefit to vitamin A alone, and adding vitamin A to multivitamins somewhat reduced their benefits.

Although men were not studied, multivitamins are likely to benefit them as well, Fawzi said.

According to Fawzi, the high-dose multivitamins with vitamins B, C, and E used for the study cost about $15 for a year's supply; AIDS drugs in Tanzania cost about $300 a year.

Still to be answered, Fawzi said, is whether lower-dose vitamins would work and whether vitamins would help those already taking AIDS drugs.

In an accompanying editorial, Drs. Barbara Marston and Kevin M. De Cock of the U.S. Centers for Disease Control and Prevention in Kenya said more study is needed to confirm the findings.

But in the meantime, doctors "would be justified in routinely prescribing this nutritional support, since it may provide a benefit and does no harm," they wrote.