The prevention of osteoporosis has largely focused on calcium supplements. While we can’t have strong bones without calcium, it isn’t enough. Bone mineral density is determined by complex metabolic processes involving a wide variety of vitamins and minerals, hormones, bone cells, and even external forces. Bones provide structure and protection for the body, but they are also an active organ, storing and releasing minerals like calcium as needed for the normal function of cells, muscles, and nerves.
Like all tissues in the body, bones are continuously remodeling themselves. Most of the adult skeleton is replaced every ten years and this balance between bone growth and bone destruction helps determine bone mineral density. It usually peaks in our late twenties or early thirties and naturally begins to decline around the age of forty.
Low bone mineral density increases the risk for fractures, which can have deadly and disabling effects for older adults. After a fracture, they are more likely to require long-term nursing care and many never return to independent living. Older adults are also more likely to die after a fracture. One study found that more than twenty percent of people aged sixty and older died during the year following a hip fracture. And according to the Centers for Disease Control and Prevention, falls are the leading cause of injury and death among adults 65 years and older in the United States.
Calcium supplements can improve bone mineral density in people who are deficient but it does nothing to prevent falls and most studies show that it does not reduce the risk of fractures. Furthermore, taking too much calcium can have adverse effects including heart attack and stroke, kidney stones, gastrointestinal problems, and the hardening of soft tissues like arteries, kidneys, the gall bladder, muscles, and breast tissue. We need a more comprehensive approach to strengthen bones, maintain bone mass as we age, and prevent falls and fractures. Here are four things that matter more than calcium.
#1 | Exercise
Different kinds of exercise contribute to healthy bones in different ways. Weight-bearing exercises that require our bodies to work against gravity—like walking, running, jumping, and stair climbing—increase mineralization and cross-linking within bones, making them more resistant to future forces. Exercises that strengthen muscles and create a force to work against—like lifting weights or using resistance machines—have been shown to reduce the risk of fractures regardless of the effects on bone mineral density. A two-year study of women between the ages of fifty-eight and seventy-five found that a back strengthening program decreased rates of spinal fractures by two-thirds even though it did not significantly improve bone scan results.
Once you get permission from your doctor, incorporate both kinds of exercise if you can. Aim for two sessions of muscle strengthening activities each week, spaced at least forty-eight hours apart so muscles can fully recover. Also be as active as you can in weight-bearing activities like hiking, dancing, racket sports, calisthenics, and yoga. Walking counts too, but only if it’s vigorous. Mechanical loading of 1.22 times the body weight is required to strengthen bone, and this translates to a walking sped of about 3.8 miles per hour and eighty-two percent of maximum heart rate.
#2 | Unipedal Standing
Unipedal standing—which is simply standing on one foot—can be an addition or an alternative to more vigorous exercise, especially for people with low mobility. Unipedal standing improves balance, which reduces the risk of falls. It also puts a mechanical stress on bone that mimics weight-bearing exercise and reduces the risk of fracture. One study found that standing on one foot increased the weight load on the femoral head of the hip by 2.75 times that of standing on two feet, and that the mechanical load of unipedal standing for one minute was equivalent to fifty-three minutes of walking.
To perform unipedal standing, stand on one foot for one minute with your eyes open. Then stand on the other foot for one minute with your eyes open. Hang on to a steady surface if you need to. For maximum benefit, do it three times each day.
#3 | A Healthy Diet
Calcium is the most well-known nutrient needed for healthy bones, but there are many others including magnesium, manganese, boron, zinc, copper, folic acid, several amino acids, and vitamins C, B6, D, and K. Our bodies can’t make vitamins, minerals, or essential amino acids, so we have to get them from food or supplements. A well-balanced vitamin-mineral formula can be a good back-up, but a healthy diet is still essential. It should include plenty of colorful fruits and vegetables, adequate protein, some oily fish, and fermented foods and green tea daily.
Green and yellow vegetables in particular have been shown to help maintain bone mass in young women. One study found that women who didn’t eat them every day had nearly five times the risk of low bone mineral density compared to those who did. For most of my patients I recommend that green and other non-starchy vegetables make up half of each meal.
I also recommend eating protein-rich foods with every meal, whether they come from plants, like beans and nuts, or from animals, like eggs and meat. In a large study using data from the Women’s Health Initiative, researchers found that eating plenty of protein (fifteen percent of total energy intake) was associated with significant increases in bone mineral density and a lower risk of fractures. Oily fish are a particularly good protein choice because the essential fatty acids they contain can help maintain calcium levels in the blood by reducing the excretion of calcium from the body.
Fermented foods like sauerkraut, natto, and cheese are good sources of vitamin K, along with eggs, liver, and meat. Vitamin K stimulates bone-building cells called osteoblasts and activates proteins that play critical roles in the mineralization of bone matrix. Green tea can improve bone mineral density and stimulate osteoblasts as well. It also suppresses bone-destroying cells called osteoclasts and studies show that it may reduce the risk of fractures.
I recommend including calcium-rich foods daily and getting enough vitamin D to maintain normal blood levels. Calcium is found in dairy products, salmon and sardines canned with bones, almonds, beans, tofu and edamame, and dark green leafy vegetables, especially collards, beet greens, and bok choy. Our skin makes vitamin D when we’re exposed to sunshine, but it’s also found in fish (especially oily fish), egg yolks, and mushrooms. We need vitamin D to absorb minerals like calcium, so eat these foods together.
#4 | Fall Prevention
Most fractures aren’t caused by osteoporosis itself. Most fractures are caused by falls. So preventing falls may be the best way to protect bones. We can do this by addressing the leading causes of falls which include poor eyesight, impaired balance, use of medications that cause dizziness and drowsiness, and hazards in the home.
Older adults should receive regular eye exams, keep glasses clean and in good repair, and wear sunglasses outside to reduce glare. They should receive regular care from a doctor who monitors medications and addresses side effects, especially those affecting balance. They should wear shoes with good support, non-slip soles, and a broad heel.
Living environments should have good lighting with sufficient switches or motion sensors, secure handrails and grab bars, and non-skid surfaces in bathtubs and showers. Homes should be free of objects that could cause tripping like cords, rugs, and clutter. Loose flooring should be repaired and spills should be wiped up immediately.
References:
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CDC (Centers for Disease Control and Prevention). Falls are leading cause of injury and death in older Americans. [Web page]. CDC website. https://www.cdc.gov/media/releases/2016/p0922-older-adult-falls.html Accessed April 1, 2021.
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Sinaki M, Itoi E, Wahner HW, Wollan P, Gelzcer R, et al. Stronger back muscles reduce the incidence of vertebral fractures: a prospective 10 year follow-up of postmenopausal women. Bone. 2002;30(6):836-41.
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