who diet excessively in the years before they become pregnant may be condemning their children to poor health in later life.
British scientists have discovered that even if such women change their eating habits once they are pregnant, their children are more likely than average to suffer heart disease, hypertension, diabetes and strokes.
Babies born to poorly-nourished mothers tend to be small and thin; they undergo irreversible changes to their metabolism and to their hormonal and circulatory systems that predispose them to disease. Improvements in diet during pregnancy are not enough to compensate for the mother�s physical condition when she conceives.
The dangers are magnified if a small baby grows slowly during the first year of life, then becomes overweight in later childhood, researchers at Southampton University found. The result is a high proportion of body fat in relation to muscle, a known risk factor for heart disease and high blood pressure that can be hard to alter in adulthood.
David Barker, Professor of Epidemiology at Southampton, said that the conditions a foetus experiences in the womb are more important risk factors for heart disease and diabetes than lifestyle and genetics. These conditions are determined largely by a mother�s body composition going into pregnancy, as her unborn child relies on protein derived from her muscles. A woman who has been seriously under-eating cannot supply her baby with enough important nutrients to sustain normal growth.
�It is the mother�s whole-life experience that counts, not just what she eats while she is pregnant,� Professor Barker told the European Society of Human Reproduction and Embryology�s annual conference in Lausanne.
Epidemiological evidence suggested a strong link between low birth weight and growth patterns in the first years of life and coronary heart disease and other health conditions. �Until recently, the general view of coronary heart disease and stroke was that they are the product of the way we live � smoking, becoming obese, diet and so on,� Professor Barker said. �These ideas are fading, they have not held up. One other set of ideas is that it is genetically determined why one person gets coronary heart disease and one does not. The trouble is we have not found the genes.
�There is a third possibility: that the diseases originate during the period in life when the body is very plastic, as the foetus is moulded by the environment it is provided with by its mother, before and immediately after birth. What you are by one to two years of age is what you will always be.�
Lifestyle becomes particularly important if a child was born small. �It is quite clear that becoming obese at any point is much more dangerous for people who were small as babies,� he said.
Maternal nutrition prior to pregnancy was the crucial factor in preventing the birth of thin babies, and the children of women who are malnourished after dieting may be at particular risk. �It is almost too late if you are not fighting fit before you conceive. I know farmers who laugh at the idea of special diets in pregnancy. They know with sheep that you move them to the best fields before they are to mate. Sadly, we know more about this for pigs, cows and sheep than for human beings.�
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