What is calcium, and what is its role in the body?
Calcium is one of the elements out of which the universe is made. It's very important for all of life. It's abundant in both fresh and marine waters. In humans, calcium is used by all cells for a variety of purposes, but perhaps most obviously calcium is the stuff that our bones are made of.
How much calcium do people need?
The Food and Nutrition Board publishes estimates of calcium requirements and the most recent ones were published in 1997. They recommend 800 mg per day up to age 8, and then 1300 mg per day through the growth years up to age 18, then 1000 mg per day out to age 50 and then 1200 mg per day thereafter.
That's the least you can get by on without some sort of a bone penalty. But the vast majority of Americans are not getting the recommended intake. Probably more than 80 percent of women, for example, are not getting the currently recommended intakes.
What are some of the primary foods sources for calcium?
The principal food sources in a modern diet, in the industrialized nations, would be dairy products, which are very calcium-rich. With dairy products, particularly milk and yogurt, the low-fat varieties provide all the nutrition of the full-fat varieties, but not the calories.
