Preventing Osteoporosis: New Dietary Recommendations

by Cora Rivard, ND

Most women, particularly after menopause, are advised by their doctors to take calcium supplements in order to help prevent development of osteopenia (reduction in bone density and strength) and osteoporosis. Osteoporosis is a condition in which osteopenia develops into severe reduction in bone mass, leading to larger spaces, or pores, within the matrix of the bone. This greatly increases the risk of fractures, and overall weakening of the skeleton.

But how is it that osteoporosis has become such a great concern in western societies, especially in the U.S., where we have access to an abundance of foods rich in calcium- such as dairy products, as well as vegetables and grains? In countries such as India, Japan, and Peru, intakes of calcium average about 300mg a day per adult, and yet the risk of osteoporosis is quite low. The nutrition part of the problem is two-fold. First, we often replace sources of whole food nutrition in our diet with foods that are calorically dense but offer little in the way of a good source of minerals and other essential nutrients. Second, some of the nutrients we ingest actually cause the body to excrete more calcium in the urine, notably the excessive consumption of sodium and protein. According to the Linus Pauling Institute in Oregon, “In adult women, each extra gram of sodium consumed per day is projected to produce an additional rate of bone loss of 1% per year…” ¹ A small study with postmenopausal women found that adherence to a low sodium diet for 6 months showed a significant reduction in urinary calcium loss, as well as reduction in the appearance of other factors noted in the breakdown of the bone matrix.

Americans, on average, consume almost twice as much protein as suggested by the RDA. Because excess protein consumption causes more calcium to be excreted by the kidneys, the recommended calcium intakes of Americans is higher than that in less industrialized countries. It is, however, important to keep an adequate intake of protein, as a diet too low in protein can also cause a greater risk of fractures. (For women, the RDA for protein is 46 grams/day for women and 56 grams/day for men.) And all proteins are not equal; proteins from animal sources leach more calcium from the bones than vegetable sources.

Though still inconclusive, there are concerns about the effects of excess caffeine over a long period of time, as well as phosphorous. Both of these ingredients are commonly found in sodas. Another concern about soda is the sugar content; a recent study shows adverse effects on bone mass when rats are given sweetened drinks over a period of time.3

Osteoporosis is a multi-factorial disease, meaning that there are other factors besides nutrition which can cause a greater risk of its development, including: smoking, long term medication use such as corticosteroids and anticonvulsants, and certain metabolic diseases.

What can you do to help prevent osteoporosis?

1. Increase consumption of foods high in calcium, and supplement if necessary. Total intake (diet + supplementation)  for women over 51 years of age should be approximately 1200mg per day. Most adults should aim for consuming a total of 1000mg of calcium per day.
2. Intake of at least 400IU of Vitamin D per day. It is also important to get outside and get minimal exposure to sunlight each day to stimulate vitamin D production in the skin.
3. Eat a well balanced diet of fresh vegetables, whole grains, and proteins. When consuming dairy products, make sure they are from high quality sources- preferably hormone and antibiotic-free sources. And try to limit your intake of all animal-sourced foods, focus instead on adding more vegetable and whole grain sources of protein and calcium.
4. Be sure to include dark leafy greens such as cooked spinach, collard greens, and kale, they are high in calcium and offer a rich source of vitamin K, important for bone health..
5. Weight-bearing exercises and resistance training are the most helpful types of exercises for maintaining healthy bone density. Always check with your doctor before beginning an exercise program.
6. Avoid consumption of excess sodium (check labels, be especially wary of canned goods, microwave-able meals, fast foods and junk foods.) Focus on whole foods instead, so you know what goes into their preparation!.
7. Avoid sodas and excess consumption of caffeine. Instead, try herbal teas, sparkling water with a twist of lemon or lime, or just plain water.

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1. Quote and referenced information included from the website of the Linus Pauling Institute, Micronutrient Research at Oregon State University

http://lpi.oregonstate.edu/infocenter/minerals/calcium/

2. Tsanzi, E., Light, H., Tou J., “The effect of feeding different sugar-sweetened beverages to growing female Sprague-Dawley rats on bone mass and strength.” Bone. 2008 Feb 15 [Epub ahead of print]