Genetic influences on the susceptibility to overeating

A recent study, published in the International Journal of Obesity [1], found that the obesity-associated gene FTO might influence children’s responses to satiety signals.

The researchers looked at the effect of the FTO genotype status (the distribution of the A and T alleles) on the responsiveness of satiety to internal signals in a sample of 131 children, aged four to five years, whose DNA was available for genotyping.

They then looked at the children’s consumption of palatable food offered after they had eaten a meal (under conditions of satiety) and controlled for body fatness and physical activity levels.

The results confirmed the study hypothesis that the higher-risk FTO alleles (AA) were associated with significantly higher consumption of the foods. The T allele was protective against overeating by increasing satiety sensitivity.

The FTO gene is mostly expressed in the areas of the hypothalamus associated with feeding and common variants of the FTO gene have previously been associated with higher body weight [2].

The way in which the obesogenic environment contributes to the increasing rates of overweight and obesity is a popular debate. There is research to suggest that inherited individual differences in eating behaviours make some individuals more susceptible than others [3].

The study suggests that FTO may influence how responsive someone is to their internal signals of satiety, and therefore the extent to which the obesogenic environment puts them at risk for weight gain.

See WCRF UK Recommendations to find out more about the links between weight and cancer.

1. J Wardle et al. The FTO gene and measured food intake in children. International Journal of Obesity 2009; 33: 42-45
2. Stratigopoulos G et al. Regulation of the Fto/Ftm gene expression in mice and humans. Am J Physiol Regul Integr Comp Physiol 2008; 294: R1185-R1196
3. Association for the Study of Obesity (ASO): Development of the Food Preferences and Early Feeding Behaviour Conference. Genetic influence on eating behaviours in children. Clare H Llewellyn.