Calcium is the most abundant mineral in the body with more than 99% occurring in bones and teeth, where it is the central “support structure.” Therefore, it’s critically important that children of all ages optimize their calcium intake every day to ensure proper development of bones and teeth.

  • Calcium is found in many foods, but the most common source is milk and other dairy products. One 8-ounce glass of milk provides 300 mg of calcium, which is 33% of the recommended daily intake for younger children and about 25% of the recommended intake for teens.
  • Based on the USDA Food Guide Pyramid, individuals two years and older should consume two to three servings of dairy products per day, with a serving size being equivalent to 1 cup (8 ounces) of milk, 8 ounces of yogurt, or 1.5 ounces of natural cheese.
  • Calcium also can be found in fortified foods such as tofu, soy milk, and some juices—as well as in dark, leafy green vegetables such as kale, broccoli, and spinach. However, to get the same amount of calcium in one 8-ounce glass of milk, a child would have to consume 21/4 cups of cooked broccoli or 8 cups of spinach.

The recommended daily intake of calcium for infants and children ranges between 210 mg and 1,300 mg a day, depending on the age of the infant or child. However, national nutrition surveys have shown downward trends in the consumption of milk, and increased consumption of sugar-rich juices and sodas[i] among adolescents and teens.

Other studies confirm that many children aren’t getting enough calcium from diet alone. In one such study, 44% of boys and 58% of girls ages 6–11, and 64% of boys and 87% of girls ages 12–19, did not meet their recommended intake for calcium.[ii]

Inadequate calcium intake, during such a critical time, can prevent children from achieving optimal peak bone mass, ultimately increasing their risk for osteoporosis and bone fractures later in life. So the take-home message is to assess your child’s dietary intake of calcium and vitamin D and be sure to provide a supplement that delivers adequate amounts of both calcium and vitamin D to fill any gaps that may exist in their diets.

[i] U.S. Department of Agriculture. Results from the United States Department of Agriculture’s 1994-96 Continuing Survey of Food Intakes by Individuals/Diet and Health Knowledge Survey. 1994-96.
[ii] Borrud C et al. What We Eat in America: USDA Surveys Food Consumption Changes. Food Rev. 1996;14-19.

Factors Affecting Peak Bone Mass

  • Gender: Bone mass or density generally is higher in men than in women. Before puberty, boys and girls develop bone mass at similar rates, but after puberty, boys tend to acquire greater bone mass than girls.
  • Race: For reasons not well understood, African-American girls tend to achieve higher peak bone mass than Caucasian girls. And girls of Asian descent tend to have the lowest bone mass. However, because all women—regardless of race—are at significantly higher risk for osteoporosis, girls of all races need to build as much bone mass as possible to help protect against this disease.
  • Hormones: Sex hormones, including estrogen and testosterone, are essential for the development of bone mass. Girls who start to menstruate at an earlier age typically have greater bone density. Girls who have been diagnosed with anorexia as well as female athletes who have very low body-fat levels and abnormal menses are at greater risk of not achieving optimal bone density.
  • Nutrition: Calcium in particular is essential for bone health. In fact, calcium deficiencies in young people can account for 5%–10% lower peak bone mass and may increase the risk of bone fractures later in life. A well-balanced diet that includes adequate amounts of vitamins D and K, as well as the minerals calcium, magnesium, zinc, copper, and manganese, also is essential to bone health.
  • Physical Activity: Important for building healthy bones, weight-bearing activities that stimulate bone growth—such as running and jumping rope—are especially important.