The search terms included variations of the following keywords with the use of different Boolean operators: obese, obesity, morbid obesity, leptin, alpha-ketoglutarate-dependent dioxygenase FTO, adiposity, hyperphagia, high body-mass index, high BMI, weight gain, weight loss, weight control, overweight, body weight, waist-hip ratio, skinfold thickness, body adiposity index, weight cycling, overeat*, adipos*, depression, depressive disorder, major depressive disorder, adjustment disorders, depress*, psychological distress, low mood, unhappiness, melancholy, adult, and young adult. This evidence concerns the gene FTO and morbid obesity.