Serotonin-transporter promoter polymorphism modulates the ability to control food intake: Effect on total weight loss

Abstract

SCOPE:The biggest challenge for losing weight is the ability to control the amount of food eaten; the tendency to overeat is called disinhibition. Our aims were to determine whether a) the SLC6A4-promoter variant (5-HTTLPR) relates to disinhibition; b) this association could affect total weight-loss during a behavioral/dietary treatment for obesity.METHODS AND RESULTS:2961 subjects attended voluntarily five weight-loss clinics; a subsample (n = 624) was recruited for SLC6A4 genotyping. Total weight-loss, Emotional-Eating-Score and Disinhibition-Score were examined. We observed that: a) the reduced ability to control food intake (disinhibition) is implicated in the impairment to lose weight; b) SLC6A4-promoter variant is implicated in disinhibition. S carriers (low-expressing) of the SLC6A4-promoter variant had a lower inhibition capacity and showed more failure (1.6 times) to control the amount of food eaten than LL (P<0.05); other factors such as eating while bored, overeating after work at night, or craving for specific foods were associated to the SLC6A4 genotype (P<0.05); c) The combination of disinhibition (high disinhibition) and genetics (S carrier) had a higher impact on total weight loss than each factor separately.CONCLUSIONS:SLC6A4-promoter variant is associated with the ability to control food intake and interacts with emotional eating to modulate total weight loss