The British researcher David J. Barker first proposed the
developmental origins theory in the 1980s to explain a puzzling paradox:
as British prosperity increased, so did heart disease; yet
geographically, the most heart disease was found in the poorest places
in Britain. Barker found geographical associations of heart disease with
infant mortality, but not with smoking or dietary fat. Yet even infant
mortality had declined over the course of the century, just as
prosperity had gone up. When he accounted for a time lag between cause
and effect of more than 50 years, however, the paradox was
resolved—something was determining the risk of disease at or near birth,
not late in life when the disease develops.58
Barker and his team of researchers then studied the birth weight of
individuals born between 1911 and 1930 in Hertfordshire, UK. This
allowed them to study the association at the level of individuals rather
than local districts. Infants carried to term with birth weights
between 8.5 and 9.5 pounds had a 45 percent lower risk of heart disease
than infants carried to term weighing less than 5.5 pounds; they had a
similarly lower risk of stroke, a nearly 70 percent lower risk of
insulin resistance, and a slightly lower blood pressure in the seventh
decade of life. The risk declined steadily and evenly between 5.5 and
9.5 pounds and began increasing thereafter. Later, other researchers
found similar trends in the United States and southern India.59
Data from the three-month Dutch famine that occurred during World War
II suggests that specific types of diseases are associated with
specific windows of development during pregnancy. Women who were exposed
to this famine during their first trimester gave birth to offspring
with an increased risk of cardiovascular disease; women exposed during
their second trimester gave birth to offspring with an increased risk of
kidney disease; women exposed during their third trimester gave birth
to offspring with an increased risk of insulin disorders.60
Developmental origins theorists have offered several explanations for
these associations: poor nutrition could alter the development of the
pancreas, which secretes insulin, and the liver, which secretes
cholesterol and blood clotting proteins; muscle tissue could program
itself for insulin resistance in order to spare glucose and amino acids
for the brain when the supply of these materials is limited; overgrowth
of the left ventricle of the heart—which itself is independently
associated with cardiovascular disease—could be a response to the need
to supply a greater volume of blood to the brain at the expense of the
other tissues.59
Just as Weston Price had associated the skeletal defects that occur
because of poor prenatal nutrition with the risk of disease in childhood
and adolescence, researchers are now associating the defects of the
internal organs that occur due to poor nourishment with the risk of
disease in adulthood and old age.
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