The involvement of brain serotonin in excessive carbohydrate snacking by obese carbohydrate cravers.
A specific hunger for carbohydrate-rich foods has been observed in animals and human beings and appears to be regulated by the brain neurotransmitter serotonin. Consumption of a carbohydrate-rich meal increases the synthesis and release of brain serotonin (by enhancing the brain uptake of its precursor, tryptophan). As a consequence of this increased release of serotonin, carbohydrate intake is decreased at the next meal. Consumption of protein does not increase brain serotonin levels or decrease carbohydrate intake. A subgroup of obese individuals who consume carbohydrate-rich snack foods at specific times of day or evening has been identified. Such individuals do not routinely snack on protein-rich foods, and their consumption of calories and nutrients at meals is not excessive. Evidence is presented that carbohydrate snacking seems to be related to a "need" to increase the level of brain serotonin; treatment with a drug, d-1 fenfluramine, that increases serotoninergic neurotransmission significantly decreases carbohydrate snack consumption. Weight loss among the population of carbohydrate cravers might be most successful if treatment includes either a diet or drugs that increase brain serotonin activity when the need to snack on carbohydrate is most likely to occur.
D000328:Adult; D000818:Animals; D001921:Brain / Q000187:drug effects* / Q000378:metabolism; D004040:Dietary Carbohydrates / Q000494:pharmacology*; D004044:Dietary Proteins; D005277:Fenfluramine / Q000494:pharmacology* / Q000627:therapeutic use; D005518:Food Preferences / Q000187:drug effects; D006801:Humans; D009765:Obesity / Q000178:diet therapy / Q000188:drug therapy; D012701:Serotonin / Q000502:physiology*
D004040:Dietary Carbohydrates; D004044:Dietary Proteins; D005277:Fenfluramine; D012701:Serotonin