Dairy Products, Vitamin D, and Bone Health

Abstract

Osteoporosis is a major public health problem affecting over 200 million people worldwide. Dairy foods such as milk, cheese, and yogurt provide a unique set of nutrients, such as calcium, protein, vitamin D (in fortified dairy), magnesium, and potassium, which are thought to be beneficial for bone health. There is strong evidence for a positive association between milk and areal bone mineral density (aBMD), and limited evidence for yogurt intake with BMD looks promising. However, data on cheese and cream is very limited. Vitamin D is involved in calcium homeostasis, suggesting that both adequate levels of calcium and vitamin D are needed to ensure optimal calcium absorption. Results from the Framingham Study demonstrated that a higher intake of dairy foods (milk, milk + yogurt, and milk + yogurt + cheese) was protective against bone loss among vitamin D supplement users but not among nonusers. This suggests that adequate vitamin D levels may provide bone-protective benefits with higher dairy intakes. Only few studies have examined the association of dairy food intake with novel measures of bone, derived using quantitative computed tomography (QCT) and high-resolution peripheral QCT (HR-pQCT). These studies show positive associations at the radius, tibia, and spine with high dairy intakes. Future studies of dairy products should focus on (1) novel measures of bone beyond aBMD and (2) specific dairy foods (3) and should consider vitamin D status.