Obesity triggers high blood pressure, high blood sugar, and lipid abnormalities, leading on to such serious diseases as arteriosclerosis, heart attack, stroke, dementia, and diabetes. It would thus be fair to say that obesity truly is the prime culprit in lifestyle diseases. Remedying obesity is also a pressing issue in order to extend healthy life expectancy and curb medical expenses, but there was hitherto no effective means of combatting it. However, scientists have now shed light for the first time on the mechanism via which the numerous mitochondria in brown adipocytes mediate the activation of this type of adipose tissue and thereby encourage fat burning. Hopes are growing that this will be the trump card in tackling obesity.