Discover K-Power

The likes of lettuce, kale, spinach, avocados, and broccoli supply vitamin K, which might fight off hip fracture when consumed in adequate amounts.

A study of 72,327 female nurses over a 10-year period A\found that women who ate lettuce at least once a day were less than half as likely to break a hip than those who ate lettuce no more than once a week. Researchers credited vitamin K for these promising results.

According to bone researcher Diane Feskanich, Sc.D., little-known vitamin K promotes the chemical conversion of a specific bone protein known as osteocalcin. Once this transaction has occurred, osteocalcin can do its job of strengthening bone tissue. In other research, people who took vitamin K supplements lost less calcium in their urine and showed better one mineral density than people who didn't take vitamin K. Still other research links low concentrations of vitamin K to low bone mineral density and bone fractures.

No one knows exactly how much vitamin K it takes to keep bones healthy and strong, but it could be much more than the Recommended Dietary Allowance of 65 micro-grams for women and 80 micro-grams for men (which are set to stave off blood clotting, not to strengthen bone). Dr. Feskanich's own study suggests that women may need 109 micro-grams a day or more to fend off fractures.

The good news is that it's not too hard to get your K if you eat salad, because it's plentiful in leaf lettuce, endive, watercress, and spinach. If you don't like greens alone, add cooked dark greens such as kale or spinach to soups, stews, omelettes, and frittatas. A mere half-cup of cooked cabbage, spinach, kale, or collard greens is more than enough to meet the 109 micro-gram level. Brussels sprouts, broccoli, soybean oil, and whole eggs also supply you with vitamin K.

One caveat: If you take the prescription medication warfarin (Coumadin), ask your doctor before increasing vitamin K. The two work against each other.

—Diane Feskanich, Sc.D., is a researcher and instructor at Harvard Medical School in Boston.

Pineapple-Rice Medley

2xh cups cooked medium-grain brown rice
1 cup chopped pineapple V2 cup raisins
V3 cup chopped toasted almonds V4 cup chopped green onions XA teaspoon ground allspice
2 tablespoons olive oil
2 tablespoons lime juice

Combine the rice, pineapple, raisins, almonds, onions, allspice, oil, and lime juice in a large bowl and chill before enjoying.

Makes about 4% cups.

—Forrest H. Nielsen, Ph.D., is the center director and research nutritionist at the United States Department of Agriculture Grand Forks Human Nutrition Research Center in Grand Forks, North Dakota.

Don't Forget Manganese

Talk about obscure. Manganese is a mineral truly living in the shadows, but it has an important role in heading off osteoporosis.

Pity poor manganese. Few people know it even exists, and when they hear about it, it's often confused with another mineral, magnesium. That's probably all right. Both contribute to bone health throughout your lifetime, says Forrest H. Nielsen, Ph.D.

Studies suggest that manganese is needed to form the proper matrix on which calcium is deposited to form bone. There are suspicions that manganese helps prevent calcium losses for women who are past menopause, says Dr. Nielsen.

On the other hand, manganese deficiency could lead to bone abnormalities, he warns. Be sure to get an adequate intake of 2 to 5 milligrams a day.

It makes sense to eat foods rich in manganese, including whole grains, nuts, leafy vegetables, and tea—as well as pineapple, which contains 2.6 grams of manganese per cup of the diced fruit.
This salad stars three manganese-rich foods—pineapples, rice, and almonds—and has more than 8 grams of manganese.