760. Physical activity attenuates the effect of the FTO genotype on obesity traits in European adults: The Food4Me study
Commentary by Rona Macniven, GlobalPANet Executive, The University of Sydney
Studies have demonstrated that the development of obesity is due to a complex number of genetic and lifestyle factors, including a genotype called FTO, and of course physical activity. While the evidence of the existence of FTO and its link with obesity is established, it may only account for a small effect on the population variance of body mass index (BMI). This multi-country study examined whether the effect of FTO loci on obesity-related traits could be modified by physical activity.
Over one thousand adults from Ireland, the Netherlands, Spain, Greece, UK, Poland and Germany (average age 40 years) had their cell DNA extracted and genotyped for FTO (rs9939609). Their physical activity was measured objectively using accelerometers and classified according to World Health Organization recommendations and their body mass index (BMI) and waist circumference self-reported. Linear regression models assessed associations among variables.
The presence of the FTO genotype was associated with all three weight measures; higher overall body weight [b: 1.09 kg per risk allele, (95% CI: 0.14-2.04), P50.024], BMI [b: 0.54 kg m22, (0.23-0.83), P<0.0001], and WC [b: 1.07 cm, (0.24-1.90), P50.011]. Physical activity had a strong interaction effects on this association where moderate-equivalent activity attenuated the effect of FTO on BMI (P[interaction] 50.020). FTO increased BMI by 1.06 kg m-2 per allele (P50.024) in inactive individuals, but the increase in BMI was substantially attenuated in active individuals (0.16 kg m22, P50.388). Being physically active also influenced waist circumference where the FTO risk allele increased WC by 2.72 cm per allele among inactive individuals but by only 0.49 cm in active individuals.
These findings clearly demonstrate the positive effects of physical activity in moderating weight gain and can be used to advocate for physical activity promotion among those who are more genetically susceptible to obesity. As more is discovered around the effects of genes on obesity, we can be confident that physical activity remains a crucial health enhancing behaviour for all; and may be particularly useful in preventing obesity in at-risk individuals.
Source: Obesity Early View. Access to this article will depend on your institutional rights. Click here for the full article.