Six-Year Diet Study: Nutrients May Reduce AIDS Risk

A major epidemiological study published this month suggests
that a number of nutrients, whether obtained from food or
nutritional supplements, might reduce progression to AIDS in
persons with HIV. The study is difficult to interpret, and it
does not prove that any nutrient is helpful in preventing
progression; to do that would require assigning people
randomly to take different amounts of nutrients for a long
time -- a very difficult and expensive study to do. Since we
will probably never have definitive proof, people need to
make decisions on information already available. The new
information suggests that nutrition should be taken more
seriously than in the past. But it would be a mistake to base
recommendations too quickly on a preliminary study.

The recent paper(1), published in the August 1993 Journal of
Acquired Immune Deficiency Syndromes, is based on data from
the San Francisco Men's Health Study. In 1984 this study
enrolled single men, ages 25 to 50, both HIV positive and HIV
negative, from the 19 census tracks in San Francisco with a
high incidence of AIDS; then the men were seen every six
months. They filled out a standard nutritional questionnaire,
and returned it to the study before they received their first
HIV test result. Therefore, the study has the advantage of
representing the entire population in the AIDS-impacted
areas, not just those who were ill and sought treatment. And
the questionnaires were returned before participants knew
their HIV status, avoiding possible bias in how they were
filled out. A total of 296 men, all healthy and HIV positive,
met all necessary criteria and were included in the nutrition
study. Thirty six percent of them progressed to AIDS during
the six years.

Special computer software analyzed the nutrition
questionnaires, with peoples' reports of their dietary
habits, to estimate how much of various nutrients they
received from food. Those who also took nutritional
supplements were asked to provide the relevant information,
often directly from the labels on the bottles. After six
years, the data were analyzed to see if total intake of
particular nutrients was associated with a difference in the
rate of progression to AIDS.

Results

The results can be confusing and hard to interpret, because
often they depend on which statistical corrections were used;
the researchers tried different ways. But the data seems to
show that:

* With certain statistical adjustments, "The hazard of AIDS
decreased as consumption increased for all 11 micronutrients
[vitamin A, carotene, retinol, vitamin C, vitamin E, folic
acid, riboflavin, thiamine, niacin, iron, and zinc]; this
relationship was statistically significant for iron, vitamin
E, and riboflavin, and approached significance for vitamin C,
thiamine, and niacin." But with other ways of looking at the
data, there was no statistically significant association of
any of the micronutrients with AIDS.

* "Higher intake of all 11 micronutrients was associated with
higher CD4 counts at baseline, and was significantly so for
six of them."

* With certain statistical adjustments, those who took daily
multivitamin supplements were only 70 percent as likely to
progress to AIDS as those who did not.

* On the other hand, those who smoked cigarettes were
significantly more likely to develop AIDS than those who did
not.

However, because this study was not a randomized trial, and
because of difficulties in interpreting the data, the
researchers could only conclude that "the possibility that
higher nutrient intakes may delay the development of AIDS
cannot be ruled out."

A different limitation of the study is that it could not
measure certain other potentially important nutrients,
including vitamin B12, vitamin B6, and copper, because the
computer software used to analyze dietary habits did not
assign values for them.

Comment

During the AIDS epidemic, some physicians and nutritionists
have developed nutritional-supplement recommendations for
persons with AIDS or HIV. (For example, see Immune Power: A
Comprehensive Healing Program for HIV, by Jon Kaiser, M.D.,
who has an AIDS practice in San Francisco; this book was
published last month by St. Martin's Press in New York.)
Since some vitamins and minerals can be dangerous in
overdose, especially for persons in poor health, it is
important to find out what has already been done in HIV care,
before starting any high-dose regimens. It is also important
to check with one's physician, because there may be
particular reasons that one should not take certain
nutritional supplements.

Incidentally, the median intake of the nutrients measured in
the study was not especially high. A graph in the published
paper showed intake levels for nine of the 11 micronutrients.
Vitamin C was highest, with a median intake between eight and
nine times the RDA (Recommended Daily Allowance of the U.S.
Food and Drug Administration, for healthy men between ages 25
and 50 -- many suspect that the RDAs are too low for persons
with HIV, because of malabsorption or for other reasons).
None of the other eight nutrients even reached four times the
RDA.

References

1. Abrams B., Duncan D., and Hertz-Picciotto I. A
prospective study of dietary intake and acquired immune
deficiency syndrome in HIV-seropositive homosexual men.
JOURNAL OF ACQUIRED IMMUNE DEFICIENCY SYNDROMES. August 1993;
volume 6, number 8, pages 949-958.