The Bone Robbers
Part Two

Keeping your bones strong as you age is not as easy as popping calcium supplements and drinking milk. There are potential “bone robbers” that may be lurking in your lifestyle.

Too much pre-formed Vitamin A (which is not the same as beta-carotene) increases the risk of fractures. The Harvard School of Public Health advises against supplements with 5,000 units of pre-formed vitamin A unless prescribed by your doctor because many foods are already fortified with vitamin A. Beta-carotene does not increase the risk of fractures.

Long-term use of corticosteroids can lower bone mass density. Other medications like anticonvulsants, thyroid medicines, certain diuretics and blood thinners can cause bone loss or deficiencies in calcium and/or vitamin D.

A 2006 Tufts University study found that elderly women (average age a little below 60) who drank four 12-ounce colas (regular or diet) a week for four years had 4% lower bone density than women who drank less than one cola a week. Men were not affected and neither were women who drank other types of soft drinks.

The low bone density findings were the same regardless of age, menopause, calcium and vitamin D intake, and smoking or drinking habits.

The researchers suspect either caffeine or phosphoric acid in colas might be to blame. Caffeine increases calcium loss in the urine while phosphoric acid can leach calcium from bones.

Phosphorus is a mineral that the body uses together with calcium to make bones. Some studies show that a high-phosphorus intake is only harmful to bones if the diet is deficient in calcium. Phosphorus isn’t just found in sodas. It is also in white flour products, processed meats, instant soups, and some breakfast cereals.

Protein doesn’t just build muscle. It is also an integral part of bones in the form of collagen. Research suggests that very low-protein and very high-protein diets can be harmful to bones.

But how much protein is too much? Is vegetable protein better than animal protein? Currently, the studies are conflicting.

2003 Creighton University: Elderly women (65 to 77) with the highest intake of protein (72 grams of protein per day and 408 mg of calcium) had higher bone density in the spine and total body but not the hip. A 1974 study of young men found similar results. A higher protein diet increased calcium absorption but only if calcium intake was above 500 mg a day.

1999 Utah State University: A lower risk of hip fracture among older women and women (50 to 69) was associated with a higher intake of animal protein compared to those taking vegetable protein.

2001 University of California, San Francisco: Elderly women who ate a meat-rich diet had lower bone density in the hip and greater risk of hip fractures than those who got their protein from vegetable sources.

1996 Harvard School of Public Health: Women who ate red meat five times a week had a higher risk of forearm fracture than women who ate red meat less than once a week. Women who ate more than 95 grams of protein per day also had a higher risk of forearm fracture than women who ate less than 68 grams per day. The increase in risk was associated with animal protein but not with vegetable protein.

Vegan warning
1997 Kaohsiung College, Taiwan: Post-menopausal Buddhist nuns who followed a strict vegan diet (absolutely no animal products) for many years were found to have a higher risk of lumbar spine fractures. The nuns’ diet may have been deficient in vitamin B12, which is only found from animal sources.

A Tufts University study found that women with low levels of vitamin B12 (less than 6 mcg) had less dense spines, while men had less dense hipbones. Nutritionists usually recommend B12 supplements for vegans.

A 2005 Purdue University study discovered that black and white young females absorb and assimilate salt and calcium differently. This may explain why blacks have a higher rate of hypertension but a lower rate of osteoporosis. The opposite is true for whites. However, the study uncovered that “too much salt reduces bone density in both races”.

According to a 1995 Australian study on post-menopausal women, the higher the sodium intake, the greater the loss of bone density in the hips. Sodium is present in many processed foods even those that don’t taste salty.

A review of other studies indicates that reducing salt intake and increasing potassium in the diet helps to reduce bone loss. Potassium is found in bananas, tomato and orange juice, melons, potatoes, and spinach.

Here’s something to really be depressed about. A study found that pre-menopausal women with major clinical depression had low bone density comparable to that of postmenopausal women. Another study found that women with past or current depression had lower bone density than women without depression. There is speculation that the stress hormone cortisol might be involved.

Anti-milk activists claim that a high intake of milk is a major cause of osteoporosis. This is a highly controversial issue. If ever proven true, it would be most ironic considering the aggressive milk moustache campaigns.

At the heart of the debate is the observation that countries with the highest dairy intake have the highest osteoporosis rates.

However, much more research is needed before any conclusion can be drawn. There are just too many other factors that affect bone health like vitamin D, magnesium, and physical lifestyle.

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