Obesity has always existed in human populations, but until very recently was comparatively rare. The availability of abundant, energy-rich processed foods in the last few decades has, however, resulted in a sharp rise in the prevalence of obesity in westernized countries. Although it is the obesity environment that has resulted in this major healthcare problem, it is acting by revealing a sub-population with a pre-existing genetic predisposition to excess adiposity. Genetics is the study of heredity. Heredity is a biological process where a parent passes certain genes onto their children or offspring. Every child inherits genes from both of their biological parents and these genes in turn express specific traits. Some of these traits may be physical for example hair and eye color and skin color etc. On the other hand some genes may also carry the risk of certain diseases and disorders that may pass on from parents to their offspring. Some children are at greater risk of obesity because of genetic factors. They have inherited genes from their parents that make their bodies gain weight easily. This would have been a very good trait hundreds of years ago, when food was hard to find and people were very active. Today, though, this can work against people who have these genes. When children eat more than they need, their bodies store the extra calories in fat cells to use for energy later. If their bodies do not need this stored energy, they develop more fat cells and may become obese. Although genetic factors can contribute to childhood obesity, these factors are rarely the sole contributor. Scientists note that genetic characteristics haven't changed since 1980, yet childhood obesity rates have tripled, according to the Centers for Disease Control and Prevention. Although your child may be genetically predisposed to obesity, a commitment to a healthy lifestyle through physical activity and diet can help minimize genetic factors.