Tryptophan and high-carbohydrate diets as adjuncts to smoking cessation therapy

Treatments that reduce the immediate effects of smoking withdrawal have potential for helping smokers quit. Serotonin-enhancing substances, such as tryptophan and high-carbohydrate diets, have been used in clinical disorders to relieve negative affect, a classic symptom of cigarette withdrawal. This research project investigated the use of tryptophan (50 mg/kg/day) and high-carbohydrate diets, together with more traditional smoking cessation treatment techniques, to ameliorate the smoking withdrawal syndrome and to improve abstinence rates. Subjects were randomly assigned to receive either tryptophan (n=16) or placebo (n=15). Standard smoking cessation treatment was identical for the experimental and control groups and consisted of four 2-hr weekly sessions of multicomponent group therapy. Smoking behavior, symptoms of nicotine withdrawal, and negative affect were assessed during a 2-week withdrawal period. Tryptophan-treated subjects who could not fully abstain were able to smoke fewer daily cigarettes. Reported anxiety and other withdrawal symptoms were lower in the tryptophan group compared with control subjects. These data suggest that serotonin-enhancing substances show promise for use as an adjunct to existing smoking cessation programs.