BMI was higher among: younger adults (aged 18–29 years: 35.2 kg/m2 [IQR 29.7–41.1]); females (31.1 kg/m2 [IQR 26.9–36.2]); those in the most deprived IMD quintile (31.0 kg/m2 [IQR 27.1–35.8]); those with mental health conditions including depression (31.6 kg/m2 [IQR 27.6–36.5]); and those taking insulin (31.3 kg/m2 [IQR 27.4–36.0]). The gene discussed is INS; the disease is major depressive disorder.