Theaim "to boost the serotonin levels in the brain", via tryptophan supplementation, probably should be a shortterm approach because both of these substances are linked to brain dysfunction, inflammation, blood vessel constriction, free radical generation, cancer, and so forth (review Tryptophan Side Effects: L-Tryptophan Is Far From Harmless). The need to smoke seems to be caused primarily by early childhood/prenatal trauma.Addressing those with a deep psycho-physiological therapy is likely going to proffer more profound and long-lasting benefits for the "habit".