Update on Micronutrient
Needs in HIV
by Alan Lee, RD, CDN, CFT
Micronutrient deficiencies
appear to be common in person(s) living with HIV/AIDS (PLWHA)
as a result of HIV infection itself, malabsorption, and/or
eating less due to being HIV positive. Even PLWHA who are
asymptomatic or appear to eat a well-balanced diet may be
deficient or in the low normal range for certain nutrients.
Whole foods, fruits and vegetables,
and lean protein are a paramount part of a PWLHA’s diet. There
are many vitamins, minerals, and antioxidants, like vitamin
A and C, available in fruits and vegetables for optimal health.
There are many other antioxidants, such as polyphenols, flavonoids,
allium compounds, and glucosinolates in fruits/vegetables
as well. Research on these nutrients is continuing and new
findings are emerging. By consuming whole foods, such as whole-grains,
fruits and vegetables, a PLWHA is including these and other
antioxidants as well that may turn out to be very beneficial.
In a perfect world, eating
a variety of healthy foods is all a PLWHA would need to do
in order to meet all their nutritional needs. But we do not
live in a perfect world and a prudent amount of “insurance”
in the form of a supplement makes sense, especially if a PLWHA
has a poor appetite or is experiencing nausea. There are certain
micronutrients like vitamin E that cannot be eaten in high
enough quantities in foods for an antioxidant level dosage.
Remember, however, that taking supplements is no excuse for
poor dietary habits. PLWHA should discuss their eating habits
with a Registered Dietitian (RD) and have the RD compare their
eating habits and intake to their estimated needs.
Much of the published research
conducted on micronutrient intake in PLWHA to predict morbidity
and mortality studied individuals before the advent of highly
active anti-retroviral therapy (HAART). It is still too soon
to tell what effects HAART may have on micronutrient needs.
One recent study by Rosseau et al. evaluated 44 patients while
on HAART in 1998 and found HAART contributed to selenium and
zinc deficiencies. This is consistent with published data
that shows people with AIDS tend to have more severe selenium
deficiencies than those who have a healthier immune system.
It is outside the scope of
this article to review every micronutrient in depth, but rather
to highlight certain micronutrients (selenium, vitamin B12,
vitamin A, C, and E) that have considerable amounts of research
in relation to HIV in the medical literature.
Selenium
Selenium is part of the body’s
antioxidant defense system. It is a component of the enzyme
gluthathione peroxidase. Selenium is the most studied micronutrient
to date, with profound nutritional implications for PLWHA.
Low selenium levels are associated with low gluthathione activity.
A landmark study by Baum et al. in 1997 looked at 125 HIV
positive intravenous drug users in Miami. This cohort was
followed in 6-month intervals for 3.5 years. Only a selenium
deficiency and CD4 count were shown to be significantly associated
with mortality. The relative risk of mortality with selenium
deficiency was almost 11 times greater, and was statistically
significant. These results indicate that selenium deficiency
is an independent predictor of survival.
A recommended daily selenium
intake can range from the Daily Value (DV) of 70 mcg to 200
mcg. Keep in mind however that the DV is established by the
FDA (Food and Drug Administration) to represent the minimum
amount required to prevent a clear deficiency in a healthy
sedentary adult population without chronic diseases. I hazard
to state that the DV’s do not apply to the majority of PLWHA.
The Upper Tolerable Limit (UTL) set by the National Academy
of Sciences for selenium is 400 mcg. The best sources of selenium
from food are Brazil nuts, seafood, liver, meat and grains.
Vitamin B12
B12 is a water-soluble vitamin
and important in the formation of proteins, messengers in
the nervous system, red blood cells, proper functioning of
a large number of enzymes and in maintaining a good immune
system. B12 absorption requires intrinsic factor, a glycoprotein
made in the gastrointestinal tract that allows it to be absorbed
in the small intestine. B12 deficiencies may occur in malabsorption
and in PLWHA. The symptoms of a B12 deficiency include anemia
and changes in mental function that can lead to dementia.
Tang et al. studied 310 HIV positive participants for nine
years from 1984–1993 and found that people with low serum
B12 levels (<120pmol/L) had significantly shorter AIDS-free
time than those with normal B12 levels (>120pmol/L). The
average AIDS-free time was 4 years vs. 8 years respectively.
The risk of progression to AIDS for those with low B12 levels
was significant with a relative hazard of 2.21 (the risk was
more than doubled), which shows that low B12 levels precede
disease progression.
A recommended daily B12 intake
can range from the DV of 6 mcg to 1000 mcg. The Physician’s
Desk Reference (PDR) for Nutritional Supplements states that
oral vitamin B12 is well tolerated even at high doses. There
is no established UTL for B12 and there is no documentation
in the literature of overdosages. The best sources of B12
from food are meat, fish, poultry, milk and eggs. A PLWHA
who is also a vegan (eats no animal products) vegetarian clearly
needs a B12 supplement.
Vitamin A and Beta-Carotene
Vitamin A is a fat-soluble
vitamin and beta-carotene (water-soluble) is the preferred
source that can be converted into vitamin A in the body. Some
studies show that a vitamin A deficiency appears to be an
independent predictor of survival and levels may be low in
PLWHA. In one study by Tang et al. in 1993 there seems to
be a U-shape relationship between progression of HIV and vitamin
A intake. This means that the highest and lowest quartiles
of intake did the poorest, while the middle two quartiles
were associated with slower progression to AIDS. Several clinical
trials since have shown no benefit beyond correcting a vitamin
A deficiency for sustained or significant improvements in
the immune system. An excess of vitamin A is toxic, may promote
free radicals, and therefore should be avoided.
A recommended daily vitamin
A and beta-carotene intake can range from the DV of 5000 IU
to 10,000 IU, which is the UTL. The best sources of vitamin
A and beta-carotene from food are green leafy vegetables,
carrots, cantaloupe, peppers, oranges, meat, milk, and other
red, green, orange or yellow colored fruits/vegetables.
Vitamin C
Vitamin C is a water-soluble
vitamin that is an important antioxidant. It also has the
ability to regenerate the antioxidant form of vitamin E. Vitamin
C has been shown in studies to reduce the symptoms and severities
in acute viral infections, such as the cold and flu. The need
for vitamin C increases with infection or injury. It is essential
for the maintenance of bones, teeth, blood vessels and connective
tissue.
A recommended daily vitamin
C can range from the DV of 60 mg to 1,000 mg. 2000 mg of vitamin
C is the UTL. The best sources of vitamin C from food are
oranges and other red, green, orange or yellow colored fruits
and vegetables.
Vitamin E
Vitamin E is a fat-soluble
antioxidant that plays an important role in protecting the
cell membrane, bone marrow toxicity (possible side-effect
of AZT), fats, the immune system and vitamin A from oxidative
stress. Low levels of vitamin E in the body have been associated
with an increase in oxidative stress in PLWHA. In vitro (in
the test tube), vitamin E appears to have an anti-viral effect.
One study by Abrams et al., with 296 HIV positive men followed
over six years, showed a decreased risk of progression to
AIDS with a doubling of vitamin E intake.
A recommended daily vitamin
E intake can range from the DV of 30 IU to 800 IU. The UTL
for vitamin E is 1000 IU. Be sure to avoid extra vitamin E
if a PLWHA is on the protease inhibitor Agenerase (amprenavir),
as it already has 1744 IU in the standard dose. The best sources
of vitamin E from food are vegetable oils, eggs, and whole-grain
cereals.
The body of research shows
micronutrient needs are typically higher for PLWHA than for
the general population. As a result, in some instances a supplement
may be warranted, in addition to a healthy well-balanced eating
plan to ensure optimal health and longevity. A basic multivitamin
with minerals once or twice a day with meals is a good foundation.
Beyond that make sure you discuss any plans on taking supplemental
forms of micronutrients with your doctor and nutritionist.
Alan Lee, RD, CDN, CFT,
is a nutrition and fitness expert and currently works as a
consultant for various AIDS Service Organizations and Astor
Medical Group, LLP (www.astormedical.com)
in New York City. He is currently the chair of Nutritionists
In AIDS Care (NIAC), which is a special interest group of
the Greater New York Dietetic Association (GNYDA). He coordinates
the group’s annual conference, as well as the NIAC lecture
series for nutritionists on continuing education topics. He
is a national speaker on nutrition and fitness and can be
reached at AlanLeeRD@yahoo.com
and (212) 229-2298. References are available from author upon
request.
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