Variability of macronutrient composition intake between participants may influence the measured RQ and influence the results associated with fat vs carbohydrate oxidation.41 Several studies have suggested macronutrient alterations could also influence appetite regulation.42 43 Further, individual differences in circulating insulin levels or sensitivity may confound the reported associations between RQ, REE and fat mass.14 44 45 We have taken this into account and have therefore excluded patients with diabetes mellitus or metabolic disorders. The gene discussed is INS; the disease is metabolic disease.