Calcium and vitamin D

Recommended calcium intake is:

• Children 1-5: 800 mg
• Children 6-10: 1200 mg
• Children 11-24: 1200-1500 mg

Recommended vitamin D intake is:

• Infants: 200 IU
• Children: 200 IU
• Adolescents and adults: 400 IU

These recommendations assume there is no dietary intake of calcium and vitamin D, and that there is no exposure to sunlight (vitamin D only), and are meant as guidelines only. An excellent review of current knowledge regarding vitamin D deficiency can be found in [Misra: 2008].

Calcium: Children eating a regular diet tend to get about 200 mg of calcium at baseline, and about 300 mg for each serving of dairy products, such as milk, yogurt, and cheese. Calcium-fortified orange juice contains about the same amount of calcium as an equivalent amount of milk. A few vegetables, including broccoli, rhubarb, soybeans, arugula, kale and collard greens contain smaller amounts of calcium. Calcium from food is probably more bioavailable than calcium from vitamins. High calcium intake may contribute to renal stones although in children with normal digestion, calcium absorption from the intestines is closely regulated by hormones.

Vitamin D: Sunlight, fortification of milk and cereals, and some fish contain Vitamin D. There are also numerous preparations containing calcium and vitamin D. Excess vitamin D can cause hypercalcemia and taking amounts of vitamin D over the recommended amounts should be avoided.
Also see Vitamin D information from the NIH and Calcium information from the NIH.