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Clemens RA, Hernell O, Michaelsen KF (eds): Milk and Milk Products in Human Nutrition.
Nestlé Nutr Inst Workshop Ser Pediatr Program, vol 67, pp 79–97,
Nestec Ltd., Vevey/S. Karger AG, Basel, © 2011.
Milk and Linear Growth: Programming of
the IGF-I Axis and Implication for
Health in Adulthood
Richard M. Martin
a,b
, Jeff M.P. Holly
c
, David Gunnell
a
a
Department of Social Medicine,
b
MRC Centre for Causal Analysis in Translational
Epidemiology, Department of Social Medicine, and
c
Clinical Sciences North Bristol,
University of Bristol, Bristol, UK
Abstract
There is increasing awareness that childhood circumstances influence disease risk
in adulthood. As well as being strongly influenced by genes/genetic factors, stature
acts as a marker for early-life exposures, such as diet, and is associated with risk of
several chronic diseases in adulthood. Stature is also a marker for levels of insulin-like
growth factor (IGF)-I in childhood. Levels of IGF-I are nutritionally regulated and are
therefore modifiable. Milk intake in childhood and in adulthood is positively associ-
ated with higher levels of circulating IGF-I and, in children, higher circulating IGF-I
promotes linear growth. Studies conducted by our team and others, however, indicate
that the effect of milk is complicated because consumption in childhood appears to
have long-term, programming effects which are opposite to the immediate effects of
consuming milk. Specifically, studies suggest that the long-term effect of higher levels
of milk intake in early childhood is opposite to the expected short-term effect, because
milk intake in early-life is inversely associated with IGF-I levels throughout adult life.
We hypothesize that this long-term programming effect is via a resetting of pituitary
control in response to raised levels of IGF-I in childhood. Such a programming effect
of milk intake in early life could potentially have implications for cancer and ischemic
heart disease risk many years later.
Copyright © 2011 Nestec Ltd., Vevey/S. Karger AG, Basel
Introduction
The opportunities to directly examine the relationship between early nutri-
tion and diseases in adulthood are limited because few cohort studies have
information from birth until old age. To date, therefore, most epidemiological