Thylakoid membranes from green plants affect appetite and promote body weight loss

Abstract: The incidence of overweight and obesity has reached alarming proportions. Today, overweight, obesity and the metabolic diseases cause more death than starvation. To counteract an increasing body weight gain, regulation of appetite and a controlled food intake is of greatest importance. Simply put, body weight is regulated by the amount of energy ingested, and the amount of energy expended. In todays sedentary lifestyle, we tend to have a much higher food intake than the amount of energy used by the body, resulting in body weight gain. Thylakoids are membranes extracted from chloroplasts of green leaves. They have previously been found to prolong the lipolysis and affect food intake and body weight gain in rodents, as well as affect appetite-regulating hormones in healthy volunteers. This thesis aims to explain mechanisms underlying the effects of thylakoids on food intake and body weight gain, as well as present longer time effects in humans. Results show that thylakoids promote body weight loss in humans after three months of daily supplementation. Several factors important for body weight regulation are affected by thylakoids. The digestion of dietary nutrients is prolonged after thylakoid supplementation, resulting in prolonged glucose and insulin responses. In the long run, fasting blood-glucose concentrations are also decreased. Thylakoids stimulate the release of the satiety promoting hormones cholecystokinin (CCK) and glucagon-like peptide-1 (GLP-1), while decreasing levels of the hunger promoting hormone ghrelin. Moreover, circulating levels of leptin and blood lipids are decreased after thylakoid supplementation for two and three months. Finally, thylakoids affect the subjective ratings of appetite and urge for specific food. The urge for energy dense, so called palatable food rich in fat and sugar, is specifically decreased after thylakoid intake. In conclusion, the results presented in this thesis show that thylakoids exert positive effects for body weight and appetite regulation and may thus be used as an effective tool for novel treatment of overweight, obesity and the metabolic diseases.