CRP and major depressive disorder: Impaired physical functioning, but not impaired cognitive functioning, was predicted by fruit and vegetable consumption, current smoking, sleep duration, depression, obesity/higher BMI, total:high-density lipoprotein cholesterol ratio, fasting glucose, and serum CRP at age 50 years, with heterogeneity of risk factor effects being evident for depression, obesity/higher BMI, fasting glucose, and serum CRP.