Eating behaviours and food cravings; influence of age, sex, BMI and FTO genotype

Previous studies indicate that eating behaviours and food cravings are associated with increased BMI and obesity. However, the interaction between these behaviours and other variables such as age, sex, BMI and genetics is complex. This study aimed to investigate the relationships between eating behaviours and food cravings, and to examine the influence of age, sex, body mass index (BMI) and fat mass and obesity-associated (FTO) genotype on these relationships. A total of 475 participants (252 female, 223 male, BMI: 25.82 ± 6.14 kg/m², age: 30.65 ± 14.20 years) completed the revised 18-question version of the Three Factor Eating Questionnaire (TFEQ-R18) to assess cognitive restraint, uncontrolled eating and emotional eating, and the Food Cravings Inventory (FCI) to assess cravings for fatty food, sweet food, carbohydrates and fast food. DNA samples were genotyped for the rs9939609 polymorphism in the obesity-linked gene FTO. Questionnaire data was analysed for associations between the TFEQ-R18 and FCI subscales for the whole study group, and the group divided by sex, genotype and age (≤25 years versus >25 years). Finally, mediation analysis was used to explore the relationships between BMI, cognitive restraint and food cravings. FTO AA + AT genotype was associated with increased BMI, but not with differences in eating behavior scores or food craving scores; age was associated with increased BMI and decreases in food craving scores in which this effect was stronger in women compared to men. Increased cognitive restraint was associated with decreased food craving scores in the ≤25 years group. Mediation analysis demonstrated that in this group the association between BMI and reduced food cravings was mediated by cognitive restraint indicating that in this age group individuals use cognitive restraint to control their food cravings. The positive correlation between age and BMI confirms previous results but the findings of this study show that age, sex, FTO genotype and BMI have an influence on the relationships between eating behaviours and food cravings and that these variables interact.