According to many health experts, obesity has reached epidemic proportions. This is primarily due to our environment. In the United States, we have access to lots of high-calorie foods and we don’t get enough activity to offset the calories. But our genes and their relationship to our environment may also be a contributing factor.

It’s thought that some of our genes regulate how our body uses the energy we get from food. Scientists have been studying these genes to determine if they might determine who becomes obese and who does not. One thing that they have discovered is that there may be dozens or even hundreds of genes that in some way contribute to obesity.

One theory about how genes may contribute is referred to as the “thrifty genotype” hypothesis. The basis of this hypothesis lies in the fact that although genetics can change, that change happens over very long periods of time. In the distant past, where food was not as readily available as it is today, our gene makeup may have adapted so that we could survive famines. In essence, the body learned to fatten itself up more quickly during times of abundance and hold on to fat stores to get through lean times. According to this hypothesis, these “thrifty” genes may not have adapted to today’s abundant food supply.