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According to the American Academy of Pediatrics, the goal of
pediatrics is “to attain optimal physical, mental, and
social health and well-being for all infants, children, adolescents,
and young adults.” It is self-evident that maintaining
good nutrition is a prerequisite to attaining this goal. Appropriate
nutrition supplies the “building blocks” for healthy
physical growth. Optimal mental health and mental capacity rely
on adequate nutrition, from conception to old age. D.J.P. Barker theorized
that fetal nutrition is associated with a number of chronic conditions
of later life. The Barker hypothesis, in its expanded form, proposes
that infant nutrition, as well as fetal nutrition, has long-term
health effects reaching into adulthood and old age. Some of the
parameters that may be affected by nutrition in infancy include
cardiovascular health, blood pressure, bone mineralization, low-density
lipoprotein cholesterol, split proinsulin, and cognitive development.
While these observations are tantalizing, they are observational.
A causal relationship has not been established. The Barker hypothesis
continues to be debated, but to the extent that it proves true, early
nutrition gains tremendous importance.
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Much of the early work on establishing nutritional requirements
focused on preventing diseases and deficiencies. It was assumed
that if a child were given adequate amounts and varieties of foods,
good nutrition would automatically follow. The present obesity epidemic
that has affected all age groups in our society has proven this
assumption incorrect. It has become clear that we need to monitor
the nutritional health of our youth and encourage good nutrition
for all. In order to accomplish this, we must know the nutritional
requirements for optimal growth and to avoid future nutrition-related
complications, not merely to avoid deficiency states.
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Recommended Dietary Allowances (RDAs)
were first established in 1941 and first published in 1943. The
RDAs were based on scientific evidence and intended to serve as
goals for good nutrition. Over the years the RDAs have changed according
to the needs of the country. When first devised, the country was
struggling with war-time shortages and the RDAs were used to guide
priorities and to avoid widespread deficiencies in groups of people. Over time, the emphasis
changed to goals for individuals. The eighth edition of the RDAs
published in 1974 included the following definition of RDA: “the
levels of essential nutrients that, on the basis of scientific knowledge,
are judged by the Food and Nutrition Board to be adequate to meet
the known nutrient needs of practically
all healthy persons.” The
exception to the “practically all healthy persons” rule
is the RDA for energy. Since it would not be reasonable to recommend
the high end of the distribution curve for energy, in this case
the RDA was set at approximately the average. Planning for the present Dietary Reference Intakes (DRIs), that
have superseded the RDAs, began in 1993 with the realization that
RDAs need to be “continuously” updated rather
than periodically reviewed and updated and that values beyond RDAs
were necessary. Among other things, Upper Limits ...