Lifestyle factors and ghrelin: critical review and implications for weight loss maintenance

Ghrelin, the only known appetite-stimulating hormone in humans, may be one factor involved in increased appetite, cravings and food intake following weight loss. Innovative strategies for suppressing ghrelin and decreasing appetite during weight loss maintenance are needed. Recent research has highlighted relationships between ghrelin, stress and lifestyle factors. The purposes of the current review are to (i) describe the current status of knowledge about ghrelin and lifestyle factors; (ii) critically examine research in this area, highlighting inconsistencies and methodological issues and (iii) discuss future directions and implications for obesity treatment. Based on Literature search using PsycINFO and Medline databases, we reviewed experimental studies on relationships between ghrelin, stress, exercise and sleep. Ghrelin levels are positively related to stress hormones, and stress management interventions including exercise and sleep may help to reduce acylated ghrelin and corresponding appetite. Behavioural interventions may offer a practical, cost-effective alternative for reducing or stabilizing ghrelin levels after initial weight loss. Adding behavioural techniques designed to reduce ghrelin to traditional weight loss maintenance protocols may help individuals to maintain weight loss. Future directions for investigating relationships between ghrelin and behavioural factors, examining the efficacy of behavioural programmes in reducing ghrelin and improving weight loss maintenance are discussed.