The consumption of adequate levels and proper balance of essential nutrients
is critical for maintaining health. The identification, isolation, and purification
of nutrients in the early 20th century raised the possibility that optimal
health outcomes could be realized through nutrient supplementation. Recent
attempts using this approach for cardiovascular disease and lung cancer have
been disappointing, as demonstrated with vitamin E and beta carotene. Moreover,
previously unrecognized risks caused by nutrient toxicity and nutrient interactions
have surfaced during intervention studies. The most promising data in the
area of nutrition and positive health outcomes relate to dietary patterns,
not nutrient supplements. These data suggest that other factors in food or
the relative presence of some foods and the absence of other foods are more
important than the level of individual nutrients consumed. Finally, unknown
are the implications on public health behavior of shifting the emphasis away
from food toward nutrient supplements. Notwithstanding the justification for
targeting recommendations for nutrient supplements to certain segments of
the population (eg, the elderly), there are insufficient data to justify an
alteration in public health policy from one that emphasizes food and diet
to one that emphasizes nutrient supplements.