Vitamins that may be helpful

Although insufficient when used as the only intervention, calcium supplements help prevent osteoporosis.⁴⁴ Though some of the research remains controversial, the protective effect of calcium on bone mass is one of very few health claims permitted on supplement labels by the U.S. Food and Drug Administration.

In some studies, higher calcium intake has not correlated with a reduced risk of osteoporosis—for example, in women shortly after becoming menopausal⁴⁵ or in men.⁴⁶ However, after about three years of menopause, calcium supplementation does appear to take on a protective effect for women.⁴⁷ Even the most positive trials using isolated calcium supplementation show only minor effects on bone mass. Nonetheless, a review of the research shows that calcium supplementation plus hormone replacement therapy is much more effective than hormone replacement therapy without calcium.⁴⁸ Double-blind research has found that increasing calcium intake results in greater bone mass in girls.⁴⁹ An analysis of many trials investigating the effects of calcium supplementation in premenopausal women has also shown a significant positive effect.⁵⁰ Most doctors recommend calcium supplementation as a way to partially reduce the risk of osteoporosis and to help people already diagnosed with the condition. In order to achieve the 1,500 mg per day calcium intake many researchers deem optimal, 800 to 1,000 mg of supplemental calcium are generally added to the 500 to 700 mg readily obtainable from the diet.

While phosphorus is essential for bone formation, most people do not require phosphorus supplementation, because the typical western diet provides ample or even excessive amounts of phosphorus. One study, however, has shown that taking calcium can interfere with the absorption of phosphorus, potentially leading to phosphorus deficiency in elderly people, whose diets may contain less phosphorus.⁵¹ . The authors of this study recommend that, for elderly people, at least some of the supplemental calcium be taken in the form of tricalcium phosphate or some other phosphorus-containing preparation.

Ipriflavone is a synthetic flavonoid derived from the soy isoflavone called daidzein. It promotes the incorporation of calcium into bone and inhibits bone breakdown, thus preventing and reversing osteoporosis. Many clinical trials, including numerous double-blind trials, have consistently shown that long-term treatment with 600 mg of ipriflavone per day, along with 1,000 mg supplemental calcium, is both safe and effective in halting bone loss in postmenopausal women or in women who have had their ovaries removed. Ipriflavone has also been found to improve bone density in established cases of osteoporosis in most,^{52 53 54 55 56 57 58 59 60 61 62} but not all,⁶³ clinical trials. Some studies have shown that ipriflavone therapy not only stops bone loss, it also actually increases bone density and significantly reduces the number of vertebral fractures and amount of bone pain.

However, one double-blind study has failed to confirm the beneficial effect of ipriflavone. In that study, ipriflavone was no more effective than a placebo for preventing bone loss in postmenopausal women with osteoporosis.⁶⁴ The women in this negative study were older (average age, 63.3 years) than those in most other ipriflavone studies and had relatively severe osteoporosis. It is possible that ipriflavone works only in younger women or in those with less severe osteoporosis.

Vitamin D increases calcium absorption, and blood levels of vitamin D are directly related to the strength of bones.⁶⁵ Mild deficiency of vitamin D is common in the fit, active elderly population and leads to an acceleration of age-related loss of bone mass and an increased risk of fracture.⁶⁶ In double-blind research, vitamin D supplementation has reduced bone loss in women who consume insufficient vitamin D from food⁶⁷ and slowed bone loss in people with osteoporosis.⁶⁸ However, the effect of vitamin D supplementation on osteoporosis risk remains surprisingly unclear,^{69 70} with some trials reporting little if any benefit.⁷¹ Moreover, trials reporting reduced risk of fracture have usually combined vitamin D with calcium supplementation,⁷² making it difficult to assess how much benefit is caused by supplementation with vitamin D alone.⁷³

Impaired balance and increased body sway are important causes of falls in elderly people with osteoporosis.⁷⁴ Vitamin D works with calcium to prevent some musculoskeletal causes of falls. In a double-blind trial, elderly women who were given 800 IU per day of vitamin D and 1,200 mg per day of calcium had a significantly lower rate of falls and subsequent fractures than did women given the same amount of calcium alone.⁷⁵ Vitamin D in the amount of 800 IU per day effectively prevented falls in a double-blind study of elderly nursing home residents, but lower amounts were ineffective.⁷⁶

Despite inconsistency in the research, many doctors recommend 400 to 800 IU per day of supplemental vitamin D, depending upon dietary intake and exposure to sunlight.

A preliminary trial found that elderly women with osteoporosis who were given 4 grams of fish oil per day for four months had improved calcium absorption and evidence of new bone formation.⁷⁷ Fish oil combined with evening primrose oil (EPO) may confer added benefits. In a controlled trial, women received 6 grams of a combination of EPO and fish oil, or a matching placebo, plus 600 mg of calcium per day for three years.⁷⁸ The EPO/fish oil group experienced no spinal bone loss in the first 18 months and a significant 3.1% increase in spinal bone mineral density during the last 18 months.

Vitamin K is needed for bone formation. People with osteoporosis have been reported to have low blood levels^{79 80} and low dietary intake of vitamin K.^{81 82} One study found that postmenopausal (though not premenopausal) women may reduce urinary loss of calcium by taking 1 mg of vitamin K per day.⁸³ People with osteoporosis given large amounts of vitamin K2 (45 mg per day) have shown an increase in bone density after six months⁸⁴ and decreased bone loss after one⁸⁵ or two⁸⁶ years.

Other preliminary studies have reported that vitamin K supplementation increases bone formation in some women⁸⁷ and that higher vitamin K intake correlates with greater bone mineral density.⁸⁸ Some doctors recommend 1 mg vitamin K1 to postmenopausal women as a way to help maintain bone mass, though optimal intake remains unknown.

In a preliminary study, people with osteoporosis were reported to be at high risk for magnesium malabsorption.⁸⁹ Both bone⁹⁰ and blood⁹¹ levels of magnesium have been reported to be low in people with osteoporosis. Supplemental magnesium has reduced markers of bone loss in men.⁹² Supplementing with 250 mg up to 750 mg per day of magnesium arrested bone loss or increased bone mass in 87% of people with osteoporosis in a two-year, preliminary trial.⁹³ Supplementing with magnesium (150 mg per day for one year) also increased bone mass in pre-adolescent and adolescent girls in a double-blind study.⁹⁴ Some doctors recommend that people with osteoporosis supplement with 350 mg of magnesium per day.

One trial studying postmenopausal women combined hormone replacement therapy with magnesium (600 mg per day), calcium (500 mg per day), vitamin C, B vitamins, vitamin D, zinc, copper, manganese, boron, and other nutrients for an eight- to nine-month period.⁹⁵ In addition, participants were told to avoid processed foods, limit protein intake, emphasize vegetable over animal protein, and limit consumption of salt, sugar, alcohol, coffee, tea, chocolate, and tobacco. Bone density increased a remarkable 11%, compared to only 0.7% in women receiving hormone replacement alone.

Levels of zinc in both blood and bone have been reported to be low in people with osteoporosis,⁹⁶ and urinary loss of zinc has been reported to be high.⁹⁷ In one trial, men consuming only 10 mg of zinc per day from food had almost twice the risk of osteoporotic fractures compared with those eating significantly higher levels of zinc in their diets.⁹⁸ Whether zinc supplementation protects against bone loss has not yet been proven, though in one trial, supplementation with several minerals including zinc and calcium was more effective than calcium by itself.⁹⁹ Many doctors recommend that people with osteoporosis, as well as those trying to protect themselves from this disease, supplement with 10 to 30 mg of zinc per day.

Copper is needed for normal bone synthesis. Recently, a two-year, controlled trial reported that 3 mg of copper per day reduced bone loss.¹⁰⁰ When taken over a shorter period of time (six weeks), the same level of copper supplementation had no effect on biochemical markers of bone loss.¹⁰¹ Some doctors recommend 2 to 3 mg of copper per day, particularly if zinc is also being taken, in order to prevent a deficiency. Supplemental zinc significantly depletes copper stores, so people taking zinc supplements for more than a few weeks generally need to supplement with copper also. All minerals discussed so far—calcium, magnesium, zinc, and copper—are sometimes found at appropriate levels in high-potency multivitamin-mineral supplements.

Boron supplementation has been reported to reduce urinary loss of calcium and magnesium in some,¹⁰² but not all,¹⁰³ preliminary research. However, those who are already supplementing with magnesium appear to achieve no additional calcium-sparing benefit when boron is added.¹⁰⁴ Finally, in the original report claiming that boron reduced loss of calcium,¹⁰⁵ the effect was achieved by significantly increasing estrogen and testosterone levels, hormones that have been linked to cancer risks. Therefore, it makes sense for people with osteoporosis to supplement with magnesium instead of, rather than in addition to, boron.

Interest in the effect of manganese and bone health began when famed basketball player Bill Walton’s repeated fractures were halted with manganese supplementation.¹⁰⁶ A subsequent, unpublished study reported manganese deficiency in a small group of osteoporotic women.¹⁰⁷ Since then, a combination of minerals including manganese was reported to halt bone loss.¹⁰⁸ However, no human trial has investigated the effect of manganese supplementation alone on bone mass. Nonetheless, some doctors recommend 10 to 20 mg of manganese per day to people concerned with maintenance of bone mass.

Silicon is required in trace amounts for normal bone formation,¹⁰⁹ and supplementation with silicon has increased bone formation in animals.¹¹⁰ In preliminary human research, supplementation with silicon increased bone mineral density in a small group of people with osteoporosis.¹¹¹ Optimal supplemental levels remain unknown, though some multivitamin-mineral supplements now contain small amounts of this trace mineral.

Strontium may play a role in bone formation, and also may inhibit bone breakdown.¹¹² Preliminary evidence suggests that women with osteoporosis may have reduced absorption of strontium.¹¹³ The first medical use of strontium was described in 1884. (Strontium supplements do not contain the radioactive form of strontium that is a component of nuclear fallout.) Years ago in a preliminary trial, people with osteoporosis were given 1.7 grams of strontium for a period of time ranging between three months and three years; afterward, they reported a significant reduction in bone pain, and there was evidence suggesting their bone mass had increased.¹¹⁴ More recently, in a three-year double-blind study of postmenopausal women with osteoporosis, supplementing with strontium, in the form of strontium ranelate, significantly increased bone mineral density in the hip and spine, and significantly reduced the risk of vertebral fractures by 41%, compared with a placebo.¹¹⁵ The amount of strontium used in that study was 680 mg per day, which is approximately 300 times the amount found in a typical diet. Increased bone formation and decreased bone pain were also reported in six people with osteoporosis given 600 to 700 mg of stable strontium per day.¹¹⁶   Although the amounts of strontium used in these studies studies was very high, the optimal intake remains unknown. Some doctors recommend only 1 to 3 mg per day—less than many people currently consume from their diets, but an amount that has begun to appear in some mineral formulas geared toward bone health. Strontium preparations, providing 200 to 400 mg per day, were used for decades during the first half of the twentieth century without any apparent toxicity.¹¹⁷ No significant side effects were observed in people taking large amounts of strontium; however, animal studies have demonstrated defects in bone mineralization, when strontium was administered in large amounts in combination with a low-calcium diet. People interested in taking large amounts of strontium should be supervised by a doctor, and should make sure to take adequate amounts of calcium. It should be noted that, although supplementing with strontium increases bone mineral density, only part of the increase is real. The rest is a laboratory error that results from the fact that strontium blocks X-rays to a greater extent than does calcium.¹¹⁸ People taking large amounts of strontium should mention that fact to the radiologist when they are having their bone mineral density measured, so that the results will be interpreted correctly.

Folic acid, vitamin B6, and vitamin B12 are known to reduce blood levels of the amino acid homocysteine, and homocystinuria, a condition associated with high homocysteine levels, frequently causes osteoporosis. Therefore, some researchers have suggested that these vitamins might help prevent osteoporosis by lowering homocysteine levels.¹¹⁹ In a double-blind study of people who had suffered a stroke and had high homocysteine levels, daily supplementation with 5 mg of folic acid and 1,500 mcg of vitamin B12 for two years reduced the incidence of fractures by 78%, compared with a placebo.¹²⁰ The reduction in fracture risk appeared to be due to an improvement in bone quality, rather than to a change in bone mineral density. Whether these vitamins would be beneficial for people with normal homocysteine levels is not known. For the purpose of lowering homocysteine, amounts of folic acid and vitamins B6 and B12 found in high-potency B-complex supplements and multivitamins should be adequate.

Preliminary evidence suggests that progesterone might reduce the risk of osteoporosis.¹²¹ A preliminary trial using topically applied natural progesterone cream in combination with dietary changes, exercise, vitamin and calcium supplementation, and estrogen therapy reported large gains in bone density over a three-year period in a small group of postmenopausal women, but no comparison was made to examine the effect of using the same protocol without progesterone.¹²² Other trials have reported that adding natural progesterone to estrogen therapy did not improve the bone-sparing effects of estrogen when taken alone¹²³ and that progesterone applied topically every day for a year did not reduce bone loss.¹²⁴ In a more recent double-blind study, however, progesterone had a modest bone-sparing effect in post-menopausal women.¹²⁵

In a preliminary trial, bone mineral density increased among healthy elderly women and men who were given 50 mg per day of DHEA as a supplement.¹²⁶ Similar results were found in a one-year double-blind trial that used 50 mg of DHEA per day.¹²⁷ It is not known if supplementation would have the same effect in people with established osteoporosis.

Some whey proteins may reduce bone loss.¹²⁸ Milk basic protein (MBP) is a mixture of some of the proteins found in whey protein. A preliminary trial found that 300 mg per day of MBP improved blood measures of bone metabolism in men, suggesting more bone formation was occurring than bone loss.¹²⁹ A double-blind trial found that women taking 40 mg per day of MBP for six months had greater gains in bone density compared with those taking a placebo.¹³⁰ No osteoporosis-related research has been done using complete whey protein mixtures.