Chronic disease is estimated to account for 35 million deaths worldwide. Cardiovascular disease and cancer comprise a major proportion of chronic diseases in both developed and developing countries. Other than cardiovascular disease and cancer, obesity-related diseases such as type 2 diabetes, end-stage renal disease, and osteoarthritis are also becoming significant public health problems. Many of these chronic diseases share common risk factors and underlying pathologic mechanisms that may be modified by nutrients. Examples include reduction of oxidative damage by antioxidants, DNA methylation regulated by folate and B vitamins, bone metabolism regulated by vitamin D and calcium, and cell differentiation, proliferation, and growth regulated by retinol, calcium, and vitamin D.