Are you getting enough calcium.

Calcium is essential for healthy bones, but we may not be getting as much as we need. Without healthy bones, running is risky business. The repetitive pounding can result in stress fractures of vulnerable bones. The National Institutes of Health recently increased their recommended daily allowances for calcium that most of us should consume to maximize peak adult bone mass and maintain it.

Adults, ages 25 to 50, need a hefty calcium intake of 1,000 mg per day. According to the USDA, 90% of women and 60% of men fail to consume adequate calcium for optimum bone health. Calcium requirements are even higher during childhood, adolescence, and for senior citizens. A daily intake of 1,500 mg is recommended for men and women over 65. Women have increased needs for calcium during pregnancy, breast feeding, and menopause.

The best source of calcium in the diet is non-fat or low-fat dairy products. An eight-ounce glass of skim milk provides about 300 mg of calcium and no fat. Vitamin D improves the absorption of calcium, and is usually included in most dairy products for just that reason. Some vegetables are good sources of calcium: collard greens (1 cup, 289 mg), turnip greens (1 cup, 252 mg), dandelion greens (1 cup, 252 mg), mustard greens (1 cup, 193 mg), bokchoy/kale (1 cup, 147 mg), Brussels sprouts (1 cup, 144 mg),and broccoli (1 cup, 138 mg).

Additional dietary sources are tofu, canned salmon, legumes, seeds, and nuts. Given daily requirements of 1,000 to 1,500 mg, it may be harder than you think to get what you need.

Not everyone is drinking several glasses of non-fat milk everyday, and although whole milk, yogurt, hard cheeses, and cottage cheese are excellent sources of calcium, care needs to be taken not to consume too much fat in your search for calcium. Also, some of our favorite dairy products like butter, sour cream, ice cream, and cream cheese contain minimal amounts of calcium and loads of fat.

If non-fat dairy products and calcium-containing vegetables aren't abundant enough in your diet, there are alternatives. Calcium-enriched orange juice can give you as much calcium as a glass of milk. Calcium supplements can provide the levels you need, but continue to strive to get as many nutrients as you can from food sources. (Diets rich in fruits, vegetables and non-fat dairy help you keep your blood pressure healthy, as well as provide phytochemicals, known to have many health benefits including cancer prevention.)

Calcium supplements are absorbed most efficiently when taken in individual doses of 500 mg or less, which means you need to take supplements more than once a day. (James Romeo is a freelance health and science writer living in Chesapeake, VA)

RELATED ARTICLE: Aside from building and maintaining bones and teeth, did you know that calcium also...

* helps regulate the heartbeat,

* helps the blood clot and maintain a balance of acid and alkali,

* helps muscles grow and contract,

* helps nerves transmit,

* helps the body use iron,

* helps activate enzymes so other nutrients can function,

* helps regulate the passage of nutrients in and out of the cell walls, and

* helps to prevent osteoporosis.