The average body weight loss was five kilograms and it was entirely accounted for by the loss of fat. Similarities were observed for the changes in body weight and body fat within pairs of twins, with about seven times more variance between pairs than within pairs in the response pattern. Even though there were large individual differences in response to the exercise, twins with the same set of genes were more alike in responses than subjects with different genes particularly for body fat loss and energy use. These results are remarkably similar to those of the overfeeding tests. The complexity of human obesity.
Obesity is complex and is influenced by a variety of social, behavioral andphysical elements.
Separation of the genes is not easy and whatever the influence of the gene pool on the development of obesity, it is generally by nongenetic factors. From the research currently available, a good number of genes seem to have the capacity to cause obesity or increase the likelihood of becoming obese. This may be a reflection of how most human obesity comes about. With the advent of a comprehensive human genetic linkage map, linkage studies with a large number of markers covering the complete set of genes in the human body, are likely to be helpful in the identification of obesity genes. The stage is now set for major advances in the understanding of the genetic and molecular basis of complex diseases such as human obesity.