Weight Loss Possible for People with Two High-Risk Genes


People who have two copies of the obesity gene FTO have a 2.5 greater risk of becoming overweight or obese. However, these same people can be successful at weight loss if they follow a low-fat diet, which stops the harmful effects of the gene.

In 2007, British researchers discovered the commonly occurring gene variant known as FTO that appears to explain why some people become overweight or obese while others do not. With this discovery, some people became concerned that having the obesity gene meant their weight loss efforts would be in vain. The investigators noted that the strength of the gene’s influence depends on whether a person inherits one or two copies of the FTO variant.


Specifically, they reported that people who have two copies of the FTO variant are likely to weigh 6.6 pounds more than a person who does not have the FTO variant at all. People who have just one copy are likely to weigh 2.6 pounds more than individuals who do not have the gene. Having one or two copies of the gene variant, however, does not mean people should be discouraged about weight loss.

In fact, according to the new study published in the American Journal of Clinical Nutrition, people who have two copies of the FTO variant can significantly reduce the gene’s impact through two behaviors: exercise and eating a low-fat diet, both of which can result in weight loss or help with weight maintenance. This is good news for the estimated 17 percent of the population that has two copies of the FTO gene. Another 40 percent have one copy.

In the current study, the researchers evaluated the food diaries and questionnaire and interview results from the approximately 53,000 participants of the large Malmo Diet and Cancer study, which kept comprehensive documentation on eating habits. Analysis of the data showed a clear relationship between a dramatic increase in the risk of obesity and high fat consumption in people who had two copies of the gene. It also showed, however, that people who followed a lower fat diet did not have the same risk. Therefore, the obesity effect of the gene can be canceled and weight loss is possible for people who have two copies of the FTO gene if they follow sensible lifestyle guidelines such as eating a low-fat diet and exercising.

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