Psychological and metabolic responses of carbohydrate craving obese patients to carbohydrate, fat and protein-rich meals.

RATIONALE: A defective central serotonergic neurotransmission has been suggested to result in the concomitant occurrence of an appetite disorder and a disturbed mood. This syndrome was termed carbohydrate carving (CC) obesity. Excessive consumption of carbohydrate-rich snacks would, through a plasma amino acid mediated mechanism, restore serotonergic neurotransmission and thereby relieve the symptoms of atypical depression. OBJECTIVES: To test whether CC obese patients indeed exhibit symptoms of atypical depression, whether these symptoms can be alleviated by carbohydrate-rich snacks and whether they respond differently to the snacks than non-carbohydrate craving (NC) control subjects. Furthermore, we investigated whether differences between CC and NC patients could be related to peripheral metabolic differences. DESIGN: Double blinded, randomized with cross-over. Patients received three types of snacks (100/0/0, 70/29/1 and 35/3/62 energy percent carbohydrate/fat/protein respectively) on three consecutive test days. Before and after snack administration mood and performance were tested and blood samples were obtained. SUBJECTS: 9 CC and 17 NC obese patients, matched for sex, age and body mass index. MEASUREMENTS: Mood states (Profile of Mood States and Visual Analogue Scales) and performance (Bourdon-Wiersma cancellation test), serum glucose and insulin and plasma amino acid concentrations. RESULTS: Before snack consumption, CC patients had slightly higher anger and fatigue scores and tended to have lower mood scores than NC patients. The efficiency of performance increased in both groups after all snacks. No other psychological effects of the snacks were registered. Psychological and metabolic responses of CC and NC patients to the snacks were similar. CONCLUSION: Although they may have a somewhat disturbed mood, CC obese patients do not improve their mood states through ingestion of a carbohydrate-rich snack. It seems, from a therapeutic point of view, useless to maintain the concept of carbohydrate craving.

Serotoninergic drug-induced weight loss in carbohydrate craving obese patients.

RATIONALE: Serotoninergic neurotransmission, mainly in specific hypothalamic nuclei, plays an important role in the regulation of appetite. Dysfunction of this system has been postulated to result in the clinical picture of carbohydrate craving obesity. This subgroup of obese patients is characterized by a specific preference for high-carbohydrate and low-protein snacks. Centrally acting serotoninergic drugs, such as the serotonin re-uptake inhibitor d-fenfluramine, have been hypothesized to restore serotonin mediated control of food intake. OBJECTIVE: To test the hypothesis that serotoninergic drugs would induce a greater weight loss in carbohydrate craving (CC) than in non-carbohydrate craving (NC) obese patients. DESIGN: A three months open intervention study with d-fenfluramine 15 mg twice daily. In order to be able to study the effect of the drug alone, no dietary restrictions were imposed. Both the medical doctor and the patient were unaware of who was a carbohydrate craving obese patient and who was not. SUBJECTS: 10 CC and 10 NC patients, matched for sex, age, body mass index and family history of obesity. MEASUREMENTS: Height, body weight, food intake (energy intake and macronutrient selection) and patient compliance. RESULTS: CC patients lost 4.8 +/- 3.9 kg body weight or 15.9 +/- 13.5% of their pretreatment overweight, whereas NC patients lost 4.5 +/- 2.9 kg or 16.4 +/- 11.6% of their overweight (t-test for paired samples, P = 0.82 and P = 0.93 respectively). CONCLUSION: We conclude that CC patients do not constitute a subgroup of obese patients that should be treated with a serotoninergic drug preferentially.