You probably already understand that calcium is good for your bones and helps ward off osteoporosis. The nutrient is essentially a building block of bone, and it helps maintain bone strength throughout your lifetime. But calcium can only reach its full bone-building potential if your body has enough vitamin D.

Calcium and vitamin D work together to protect your bones—calcium helps build and maintain bones, while vitamin D helps your body effectively absorb calcium. So even if you’re taking in enough calcium, it could be going to waste if you’re deficient in vitamin D.

Calcium
Your bones contain 99.5% of the total calcium in your body. Many people take in enough calcium from the foods they eat.
Good sources of calcium include:
  • Reduced-fat or skim milk
  • Low-fat plain or fruit yogurt
  • Swiss cheese
  • Calcium-fortified juice
  • Calcium-fortified cereal
  • Tofu
The daily recommended dietary calcium intake varies by age, sex, and hormone status. Recent studies have shown that many American girls do not get enough calcium in their diet after the age of 11. Many blame this on the substitution of soda for milk, yet the problem does not seem to be the same for males (1).
It is important to note that many women of all ages in the US do not get enough calcium in their diet. The vast majority of endocrinologists encourage their female patients to take supplemental calcium daily.