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Bone Health
Osteopenia and Osteoporosis
Weakening of the bones due to loss of calcium is a major bone health problem in the United States and other developed nations, and can lead to deformation of the skeleton and risk of bone fracture. There are two major categories of substandard bone mineralization. Osteopenia is defined as a bone density of 1 to 2.5 standard deviation units below that of a healthy 30 year-old (between percentiles 1 and 16 for 30 year-olds), and osteoporosis is defined as a density more than 2.5 standard deviations subpar (below the density of 99% of 30 year-olds). While the problem is much more frequent among women, over 12% of American men above age 50 suffer bone fracture due to weakened bones. Age is clearly a major factor as, after age 50, the average man loses about 5% of his current bone mass per year for a lifetime loss of close to 25%. One out of every 6 men over age 90 suffers a hip fracture, which often leads to fatal complications. Men also lose about 2 inches in height between ages 30 and 80. Even though osteopenia and osteoporosis are primarily problems of older people, the younger one adopts good bone health habits, the less likely severe bone loss will occur later in life. After age 30, it is very difficult to make up for poor prior bone health habits.
How to Prevent Bone Loss
Be wary of the following:
- Excess phosphorus: Phosphorus, along with calcium, is needed for bone development. Yet when excess phosphorus is excreted from the body, it brings calcium along with it. Carbonated soft drinks are high in phosphorus, as is meat. Thus, it is best for bone health to avoid soda and to eat meat in moderation.
- Excess protein: Many athletes and body-builders are encouraged to eat large amounts of protein. In most cases this it completely unnecessary because a typical American diet provides more than enough protein. Ingestion of excess protein has at least two downsides. The first is that all meats (e.g. beef, chicken, fish), no matter how lean, contain considerable amounts cholesterol. This can increase LDL cholesterol in the blood, raising the risk for heart disease. The second is that proteins break down to acids when digested and the body acts to maintain its normal acid-base balance by sending acid-neutralizing calcium compounds from the bones, thereby degrading bone health. This helps explain why, in societies where meat consumption is lower, people seem to need less dietary calcium to maintain healthy bones.
- Excess sodium: Just as with phosphorus, excess sodium can bring calcium along with it when it is eliminated from the body in urine.
- Excessive caffeine consumption: While the evidence is mixed, several studies show lower bone density among those who ingest large amounts of caffeine.
- Smoking: The longer people have smoked, the lower their bone density. How long one has smoked is more important than how much one has smoked.
Eat Right
- Vitamin D - This is a very important substance that controls the balance of minerals in the bone. If possible, it is best to get this vitamin from sunlight. Until recently, doctors have recommended avoiding most direct sun exposure or using powerful sun blocks. But now, there is a rising consensus that 15 minutes of sun exposure a day enhances health by generating large amounts of vitamin D in the skin. This is not only good for bone health but is associated with lower risk of several cancers even as it raises the risk of skin cancer. In northern latitudes (e.g. New York, Chicago), due to the low angle of the sun, it is impossible to get enough Vitamin D from the sun. In that case, diet and supplementation are the only alternatives to meeting the body’s need. Cold water fish like salmon, sardines, and tuna are rich in Vitamin D. To avoid mercury or other contamination, the salmon should be wild (some fresh and most canned salmon is wild), and the tuna should be light, not albacore. Supplements are never considered as good as getting nutrients from food, but Vitamin D3 is now widely recommended for people who live in higher latitudes or who get little sun exposure.
- Calcium - Bone health requires that we take in adequate amounts of calcium. However, it is not advisable for men to ingest excessive calcium because studies have linked high calcium intake with a greater incidence of prostate cancer, especially the aggressive variety. The reason is said to be that calcium reduces Vitamin D levels. Thus, the safest route to bone health is to ingest moderate amounts of calcium, limit intake of bone-depleting substances, and do the kinds of bone-enhancing exercises described below. Also, supplementation with Vitamin D may help reduce the prostate cancer risk associated with calcium ingestion. Vitamin D3 is said to be the most bioactive form of the vitamin and is most often recommended.
Exercise
Exercise is essential to good bone health. However, not all exercise provides equal benefit. Physical activities in which the limbs bear weight are the best for bone building and maintenance. Thus running, jumping, backpacking, and weightlifting are good for this purpose while swimming and cycling are not very beneficial, even though they‘re good for cardiovascular conditioning. Before beginning any exercise program, first determine that you’re healthy enough to do so. See our exercise risk questionnaire to see if you must get a physician’s clearance before you begin to exercise.
Bone Health > Disease Prevention
Bone Health > Nutrition
Physical Fitness
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