This refers to a scientific hypothesis which states that obesity in some human beings can be explained by the existence of a ‘thrifty gene’ that aided the storage of excess energy as fat. According to the hypothesis, certain genes, by helping in the storage of energy as fat, might have enabled human ancestors live through periods of famine, thus enhancing their chances of survival. The same genes, however, turned into a biological liability that led to obesity in some people. The hypothesis was proposed as an explanation for the increased prevalence of type-2 diabetes in certain populations by American geneticist James V. Neel.
