The fourth edition of my book Women's Bodies, Women's Wisdom has just been released and my seventh show for Public Television, also called Women's Bodies, Women's Wisdom, is now airing across the United States. (Go to www.pbs.org for more information.) I'm thrilled to be able to bring cutting edge health information to women--and the people who love them--for so many years. In my newest version of Women's Bodies, Women's Wisdom you'll find my advice and insights in all areas of health that are important to women--including a new pelvic health plan, new breast cancer screening advice, and ways to ramp up your sex life--based on the most up-to-date research. There's also brand new material about caring for your bones. That's what I want to discuss with you now.
While for years doctors have been recommending dietary calcium as the best way to ward off osteoporosis, many studies cast doubt on this idea. For example, a 2003 Harvard study looked at diet and hip fractures among 72,337 older women for 18 years and concluded that "Neither milk nor a high-calcium diet appears to reduce (fracture) risk."  A more recent Harvard study, this one from 2007, analyzed seven trials that followed a total of 170,991 women for several years and found no association between total calcium intake and hip fracture risk. 
The truth is that calcium isn't all it's cracked up to be when it comes to bone health. After all, in Africa and Asia, where people generally don't take calcium supplements and they consume little or no dairy (except for breastfed infants), fracture rates are 50 to 70 percent lower than they are in the US. Statistics show that most industrially advanced countries have the highest fracture rates, although they consume more dairy products than other countries.
Amy Lanou, Ph.D., an assistant professor of health and wellness at the University of North Carolina Asheville, and medical writer Michael Castleman came to a remarkable conclusion after reviewing 1,200 studies on the dietary risk factors for osteoporosis in researching their book, Building Bone Vitality: a Revolutionary Diet Plan to Prevent Bone Loss and Reverse Osteoporosis (McGraw-Hill, 2009). Of the 136 trials they found that examined the effects of dietary calcium on osteoporotic fracture risk, two-thirds of them showed that a high calcium intake does not reduce the number of fractures--even in those who took calcium (with vitamin D) during childhood. They also found that eating fruits and vegetables improved bone density in a whopping 85 percent of studies that looked at the effects of such foods.
It's not that calcium isn't valuable, it's just that it's not the Holy Grail it's been made out to be. "Think of calcium as the bricks in a brick wall of bones," Castleman writes in an article in Natural Solutions. "Bricks are essential, for sure, but without enough mortar--which comes in the form of about 16 other nutrients--the wall can't hold itself up." 
The key to preventing osteoporosis, they determined, is eating a low-acid diet. The basic idea is that a diet high in animal protein (including meat, poultry, fish, milk and dairy), grain, and high-glycemic foods (refined carbs) makes blood slightly more acidic (in part because protein is composed of amino acids). When blood is more acidic, the body tries to balance or neutralize it by adding alkaline material the only way it can--leeching some of the calcium compounds stored in bone. Eventually, osteoporosis results. It takes three servings of fruits and vegetables (which are alkaline) to neutralize the acid in just one serving of animal food (which is only the size of deck of cards), and two servings of fruits and veggies to neutralize the acid in one serving of grain. Consuming dairy foods does add back calcium, but calcium from animal sources like dairy is highly acidic, so it's like taking one step forward and two steps back.
The bottom line: For healthy bones, your blood needs to maintain a slightly alkaline pH level (a measure of relative acidity or alkalinity), which you can achieve by eating at least five servings of fruits and vegetables for every one serving of red meat, chicken or fish. Another good idea is to eat vegan--no meat or dairy--one day a week, which is very easy given the wide availability of beans, tofu and other protein these days.
Bone Health Plan
Here are some essential and specific ways to protect your bones:
Diet. Bones are dynamic organs that thrive in a mineral-rich environment. If you eat a lot of refined foods, you are likely to have weak bones and poor teeth. Follow the dietary programs outlined in Women's Bodies, Women's Wisdom, which are low-acid diets that support the health of your entire body.
Exercise. Two 40-minute sessions per week of weight training have been shown to increase bone density as much as estrogen, according to research by Miriam Nelson, Ph.D., Director of the Center for Physical Activity and Nutrition at Tufts University and author of Strong Women, Strong Bones (Perigee Trade, updated edition 2006). Dr. Nelson further reports that higher-impact activities (including vertical jumping and stair climbing), when done safely, can also help build bone. She recommends a comprehensive exercise program that includes weight-bearing aerobic exercise, strength training, vertical jumping (when appropriate and for women under 50), balance exercises and stretching. Walking, bicycling and climbing all keep bones well mineralized by placing vertical vectors of force on them.
Proper alignment of the skeleton is also crucial for maintaining healthy bones and hips throughout life. Pilates and yoga are excellent for alignment.
Reduce phosphate consumption. Phosphate consumption directly interferes with calcium absorption. Eliminate cola and root beer drinks, which have a high phosphate content.
Quit smoking and cut back on alcohol. Since smokers, along with women who consume two or more alcoholic drinks daily, are at the highest risk for osteoporosis, women should refrain from smoking and limit alcohol intake.
Limit caffeine. Caffeine increases the rate at which calcium is lost in the urine. Daily intake should be limited to no more than the equivalent of the amount of caffeine found in one to two cups of coffee. 
Decrease stress hormones. If you are depressed or under chronic stress, get help. Depression increases the risk for osteoporosis. The stress hormone known as cortisol is higher in depressed or chronically stressed individuals, and over time, this hormone results in bone (and skin) breakdown.
Vitamin D. According to Michael Holick, M.D., Ph.D., Chief of Endocrinology, Metabolism and Nutrition at Boston University School of Medicine, blood levels less than 20 ng/ml can greatly increase your risk of osteoporosis , while the lowest average blood concentration for vitamin D that demonstrates fracture reductions is equivalent to 30 ng/ml.  Consuming adequate levels of vitamin D is associated with lower risk of hip fractures in postmenopausal women, according to research from Brigham and Women's Hospital and Harvard Medical School.  Take at least 2,000 IU of vitamin D per day , aiming for an optimal level of 40-100 ng/ml.
Beta-carotene. Take 25,000 units per day (15 mg). Beta-carotene is converted into vitamin A in the body. Vitamin A promotes a healthy intestinal epithelium, which is important for optimal absorption of nutrients, and it also promotes strong joints. It is found in abundance in yellow and orange vegetables such as acorn squash and carrots and also in dark green leafy vegetables.
Natural progesterone. Progesterone's role in bone metabolism is well documented but frequently overlooked. I recommend one-quarter to one-half teaspoon of two percent cream daily on the skin.
Vitamin C. This nutrient assists in collagen synthesis and repair (in bones and skin). The recommended dose is 2,000 mg per day.  The work of Dr. Linus Pauling suggests that optimal vitamin C intake should be much higher than we've been taught. An orange provides only 60 mg per day, but Dr. Pauling's evidence is quite convincing that vitamin C is beneficial and has no side effects at levels around 2,000 mg per day or even more.
Magnesium. Though calcium gets all the credit when it comes to bone health, magnesium is equally important. Magnesium is a constituent of bone and is essential for several biochemical reactions involved in bone building. A diet low in magnesium, the norm for the standard American diet, and relatively high in calcium actually contributes to osteoporosis. Though blood levels of magnesium are often normal, this is misleading. A more accurate test is red blood cell magnesium, which is often low in cases of depression and fatigue. Overconsumption of processed food is usually the culprit in magnesium deficiency. This nutrient is found in organically grown vegetables, whole grains, sea vegetables and meats such as turkey. I recommend a magnesium supplement daily at a dose of 400 to 800 mg per day, depending upon the quality of your diet. 
Manganese. This nutrient should be supplemented in the form of manganese picolinate. The recommended dose is 15 mg per day.
Calcium. Taking calcium without vitamin D is almost useless. That said, calcium supplementation is valuable. Take 1,000 to 1,500 mg per day in the form of aspartate, citrate, or lactate. You can take less if you obtain significant amounts from your food. Despite widespread promotion of the antacid Tums as a way to obtain needed calcium, better supplements are available. Although the calcium carbonate found in Tums has been shown to increase bone density, it also exerts an alkalizing effect on stomach acid, thereby inhibiting calcium absorption and increasing the risk of kidney stones.
Boron. Boron is a trace element found in fruits, nuts and vegetables. It has been found to reduce urinary calcium loss and to increase serum levels of 17-beta estradiol (the most biologically active estrogen); both of these effects help bone health. The minimum daily dose of boron needed (2 mg per day) is easily met with a diet rich in fruits, nuts and vegetables; supplements can be taken up to 12 mg per day. 
Your bones were designed to support you for life. With a little help from you, they can do just that.
To learn more about Dr. Northrup or Women's Bodies, Women's Wisdom, go to www.drnorthrup.com.
Excerpted with permission from the fourth edition of Women's Bodies, Women's Wisdom.
Copyright Christiane Northrup, Inc. All rights reserved. Reproduction in whole or in part without permission is prohibited.
This information is not intended to treat, diagnose, cure, or prevent any disease. All material in this article is provided for educational purposes only. Always seek the advice of your physician or other qualified health care provider with any questions you have regarding a medical condition, and before undertaking any diet, exercise, or other health program.
 Feskanich, D., Willet, W.C., Colditz, G.A., 2003. Calcium, Vitamin D, Milk Consumption, and Hip Fractures: A Prospective Study among Postmenopausal Women, American Journal of Clinical Nutrition, vol. 77, no. 2 (Feb.), pp. 504-11.
 Bischoff-Ferrari, H.A., et al., 2007. Calcium intake and hip fracture risk in men and women: a meta-analysis of prospective cohort studies and randomized controlled trials, American Journal of Clinical Nutrition, vol. 86, no. 6 (December), pp. 1780-90.
 Castleman, M., July/August 2009. The Calcium Myth, Natural Solutions, pp. 57-62; available online at www.naturalsolutionsmag.com/articles-display/15403/The-Calcium-Myth.
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