Inactivity can contribute to a range of health related problems including: obesity, heart disease, metabolic syndrome, and other disorders. Researches have shown, "49 percent of heart disease in sedentary patients is due to lack of exercise" (Perkins, Whitehead, Steptoe 725) and the relative risk of metabolic syndrome was, "1.7 (95% CI 0.9–2.8) for lack of exercise, 1.5 (95% CI 1.1–2.1) for a positive family history and 2.0 (95% CI 1.2–3.4) in individuals with none or only an elementary school education versus university graduation" (Lee et al. 48).