Body Weight and Genetics

Do Our Genes Make us Fat – WHO Obesity Report

The World Health Organisation’s report on Obesity (2000) concluded that: “while it is possible that single or multiple gene effects may cause overweight and obesity directly, and indeed do so in some individuals, this does not appear to be the case in the majority of people.”

Links Between Body Weight and Genetics

Several associations between weight and hereditary genetic factors have been identified. These include:

• Intra-abdominal fat (fat around abdomen) appears to have a genetic link in the majority of cases.
• Genetics may affect the type of Basal Metabolic Rate we have. A lower-than-average BMR will lead to a tendency to gain weight.
• Appetite can be affected by hereditary factors.
• Genetics can affect the amount of fat and muscle in our body. This fat-muscle ratio has a direct effect on our BMR and thus on our weight.
• Our Thermogenesis – the amount of energy we need to metabolise food – may be affected by genetics. This, too, is likely to affect our weight.

Weight and Genetics – Conclusion

Although genetic influences do have a significant influence on body weight, human genes do not change in the space of a few decades! Therefore the huge rise in obesity among all population groups, especially in America, cannot be accounted for by genetic influence or interference.