Celeste-Teen+health-nutritionkidshealth.org

Calcium Why do we need calcium? We need calcium because it helps us to prevent bone loss. It is important that we get the amount of calcium everyday. The bone calcium begins to decrease in young adulthood and people gradually lose bone density a we get older, especially woman. Calcium also in in muscle contraction, transmitting messages through the nerves, and the release of hormones. If we don't get enough calcium, it started to take calcium away from our bones to ensure normal cell function which leads to weak bones. We need 1.300 mg (milligrams) of calcium each day. You can get calcium from these food dairy products, veggies, soy foods, beans, canned fish, calcium-fortified foods.

http://kidshealth.org/teen/food_fitness/nutrition/calcium.html