Dietary fat intake modifies the influence of the FTO rs9939609 polymorphism on adiposity in adolescents: The HELENA cross-sectional study

Nutr Metab Cardiovasc Dis. 2016 Oct;26(10):937-43. doi: 10.1016/j.numecd.2016.07.010. Epub 2016 Jul 21.


Background and aims: The fat mass and obesity associated gene (FTO) has been associated with obesity and dietary intake. The aims were: (i) To assess whether energy and macronutrient intakes were different across the FTOrs9939609 genotypes in adolescents, and (ii) to explore whether dietary fat intake modified the association of the rs9939609 polymorphism with adiposity.

Methods and results: The FTOrs9939609 polymorphism was genotyped in 652 adolescents (53% females, 14.8 ± 1.2 years, TT = 246, TA = 296, AA = 110). Energy and macronutrient intake were assessed by two non-consecutive 24 h-recalls. Weight, height, waist circumference and skinfold thicknesses were measured and body fat percent was calculated. Energy and macronutrient intake were similar across the FTOrs9939609 genotypes (P > 0.2). There were significant interactions between the FTO polymorphism and fat intake on adiposity estimates (P < 0.05). In adolescents whose fat intake was below 30% (N = 203), the A allele of rs9939609 was not associated with adiposity indices. In contrast, in adolescents whose fat intake was between 30% and 35% of energy (N = 190), the rs9939609 polymorphism was associated with a 1.9% higher body fat per risk allele (95%CI: 0.39, 3.33; P < 0.05), and in those whose fat intake was higher than 35% (N = 259), it was associated with a 2.8% higher body fat per risk allele (95%CI: 1.27, 4.43; P < 0.001).

Conclusions: These findings support the concept that the deleterious effect of the FTOrs9939609 polymorphism on adiposity is exacerbated in adolescents consuming high fat diets. In contrast, the consumption of low fat diets (<30% of energy) may attenuate the genetic predisposition to obesity in risk allele carriers.

Keywords: Adolescents; Diet composition; FTO gene; Fat intake; Obesity.

Publication types

  • Multicenter Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adiposity / genetics*
  • Adolescent
  • Alpha-Ketoglutarate-Dependent Dioxygenase FTO / genetics*
  • Cross-Sectional Studies
  • Dietary Fats / adverse effects*
  • Energy Intake
  • Europe / epidemiology
  • Female
  • Gene Frequency
  • Gene-Environment Interaction*
  • Genetic Association Studies
  • Genetic Predisposition to Disease
  • Humans
  • Male
  • Pediatric Obesity / diagnosis
  • Pediatric Obesity / enzymology
  • Pediatric Obesity / epidemiology
  • Pediatric Obesity / genetics*
  • Phenotype
  • Polymorphism, Genetic*
  • Risk Factors


  • Dietary Fats
  • Alpha-Ketoglutarate-Dependent Dioxygenase FTO
  • FTO protein, human