We often consider people lucky who remain thin even after eating so much, and when we put a morsel in our mouth, they weighing scale shoots up. New Zealand scientists have discovered new clues that help to explain why some people appear more likely than others to put on weight. They raise the novel and exciting possibility that humans may have alternate forms, designed to be fat or thin, depending on nutritional signals received during fetal life. Their study explains that the fetus takes cues from its life in the womb, such as the availability of nutrients, to expect what its future environment will be and chart a course of development that will fit it for that life. Thus, if a mother has a poor diet during pregnancy, her fetus might predict that future food supplies will be scarce and set its metabolism to store and conserve fat.

However, if this early prediction proves false and food - particularly food high in fat - is readily available, the infant may find its metabolism programmed for adult obesity and conditions such as heart disease and diabetes.
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