Osteoporosis

Selective estrogen receptor modulators. These drugs selectively bind to estrogen receptors in osteoclasts, thereby decreasing bone turnover in postmenopausal women. Raloxifene (Evista®) was the first member of this family of drugs, which have been shown to have a positive effect on a woman’s bone density (Fontana A et al 2001). Raloxifene is related to tamoxifen (Nolvadex®), which has been used to treat breast cancer for many years and is also approved for use in osteoporosis.

Studies have found significant increases in bone density with raloxifene and other drugs of this type. They are not without risk and should not be taken by people with liver disease, nor will they help with postmenopausal hot flashes.

Phytoestrogens: A Safer Estrogen?

Considering the health risks associated with conventional HRT, many women are reluctant to consider estrogen replacement therapy. Fortunately, phytoestrogens from soy, including genistein and daidzin, provide a possible alternative. We now know that genistein and daidzin bind loosely with estrogen receptors and that diets high in soy may protect against estrogen-induced cancers. Soy may also have an impact on bone health.

A six-month study to investigate bone density and bone mineral content in response to soy therapy was conducted. In this study, women received daily either phytoestrogens derived from soy protein or milk-derived protein (which contained no phytoestrogens). The results showed significant increases in bone density and bone mineral content for the lumbar spine in the women receiving the phytoestrogens derived from soy protein diets. Increases in other skeletal areas also were noted in the women on the soy diets. Researchers concluded that soy isoflavones show real potential for maintaining bone health (Potter SM et al 1998).

Another study found that soy foods reduced the risk of fracture in postmenopausal women, particularly among women who just finished menopause (Zhang X et al 2005). In this study, Chinese officials studied soy consumption among approximately 24,400 postmenopausal women and discovered that women with the highest soy intake were less like to suffer from fractures.

Ipriflavone. Ipriflavone, a synthetic isoflavone, has attracted attention and research, especially in Europe, where it is now used as a drug in treating osteoporosis. It has been shown to inhibit bone resorption and enhance bone formation in men and women. A double-blind, placebo-controlled study of ipriflavone in 255 postmenopausal women found that forearm bone mineral density remained constant for two years in the treatment group while diminishing significantly in the placebo group. Markers of bone turnover were higher in the placebo group than in the treated group. Not all studies show a bone protecting effect for ipriflavone.

Balancing Hormones For Healthy Bones

Progesterone. Although not proven by conventional standards, alternative doctors have long recommended the use of natural progesterone creams to promote osteoblasts and protect against osteoporosis. Osteoblasts require the hormone progesterone to maintain youthful bone-forming capability during and after menopause. Studies have shown that progesterone stimulates proliferation of osteoblasts (Liang M et al 2004).

California-based Dr. James Lee demonstrated increased bone density in women using progesterone cream. Since natural progesterone cannot be patented, there is little economic incentive to conduct the kind of extensive clinical trials that have been done with progestin drugs approved by the Food and Drug Administration. However, Dr. Lee studied the clinical outcomes for years and found them positive.

Parathyroid hormone and calcitonin. Parathyroid hormone (PTH) is produced by the tiny parathyroid glands, located behind the thyroid gland. PTH is partially responsible for maintaining adequate calcium levels in the blood. If calcium levels in the blood are too low, PTH stimulates calcium and phosphate resorption from the bones to ensure adequate blood calcium levels for normal body functions. PTH also causes the kidneys to decrease urinary calcium excretion.

In contrast, calcitonin, a hormone produced by the thyroid gland, stimulates calcium absorption by bones when blood calcium levels are excessive. Low levels of estrogen cause increased resorption of calcium from bones by increased sensitivity of bones to parathyroid hormone. When elevated, PTH is a good predictor of hip-bone mineral density.

Both PTH and calcitonin are sometimes prescribed to treat women with osteoporosis. Calcitonin has been shown to increase bone mass in women who are more than 5 years past menopause, while PTH is approved to treat both men and women at high risk of fracture. While side effects of PTH are generally mild, it is limited because of its mode of delivery: it is injected daily for up to two years (Kasper DL et al 2005).

Testosterone and osteoporosis in men. While osteoporosis in women tends to attract the most attention, the fact is that about 20 percent of people with osteoporosis are men, who usually suffer from the symptoms of osteoporosis about a decade later than women. Like women, men undergo a rapid loss of hormones as they age. This period is sometimes referred to as andropause and described as a period when levels of testosterone and other hormones decline. Not surprisingly, this is the same period when osteoporosis becomes a significant health concern for men.

Testosterone promotes bone formation, and many studies have shown that normal levels of testosterone are associated with higher bone mineral density and that decreased testosterone levels contribute to the development of osteoporosis (Orozco P et al 2000; Zofkova I et al 2000; Gurlek A et al 2001; Cetin A et al 2001). Low levels of free testosterone are a reliable predictor of low bone mineral density in the lumbar spine and associated with low mineral density in the hip bone (Center JR et al 1999).

Dehydroepiandrosterone. Dehydroepiandrosterone (DHEA) is a steroid hormone produced by the adrenal glands. DHEA plays many important roles in the body, including that of a precursor of testosterone and estrogen. DHEA has been shown to stimulate osteoblast activity to help prevent bone loss. Osteoblasts may convert DHEA to estrone through a reaction regulated by vitamin D3 (Takayanagi R et al 2002). DHEA levels decrease with aging, and this decrease is associated with many degenerative changes, as well as with decreased bone mineral density (Legrain S et al 2003; Buvat J 2003).

A study assessed the effects of 100 mg oral DHEA daily on a group of elderly men over a six-month period. Results indicated no adverse effects and increased bone mineral density (Sun Y et al 2002). The recommended dose for most women is about 25 to 50 mg daily.

Melatonin. Melatonin is a hormone produced by the pineal gland. It is abundant in bone marrow, where the bone cell precursors are located. It also decreases with age. Recent studies indicate that melatonin may help in the prevention of bone loss in several ways (Cardinali DP et al 2003; Ostrowska Z et al 2001; Pandi-Perumal SR et al 2003):

• Signaling the production of bone matrix proteins
• Suppressing circadian levels of certain factors related to bone metabolism
• Inhibiting osteoclast formation and bone resorption through antioxidant and free radical scavenger properties
• Promoting osteoblast proteins and procollagen type I c-peptide
• Promoting circadian growth hormone secretion

Amino Acids to Prevent Bone Loss

Proteins are constructed of various amino acids, each with a very specific function. Most amino acids are produced in the liver, and 20 percent must be obtained through diet. The amino acids not produced by the body are known as essential amino acids. L-arginine and L-lysine are essential amino acids necessary for protein synthesis; production of collagen; calcium absorption; production of hormones, enzymes, and antibodies; and tissue repair.

Several studies document the effects of essential amino acids on bone growth and metabolism, and there is sufficient support that essential amino acid supplementation contributes to bone formation and may be useful for preventing or treating osteoporosis (Conconi MT et al 2001). One animal study found that supplementation with L-arginine prevented the inhibition of bone growth and resorption of bone induced by glucocorticoids (Pennisi P et al 2005). Another study demonstrated that both L-arginine and L-lysine stimulated osteoblast cells to reproduce and activate (Torricelli P et al 2003).

Product Availability

All the nutrients and supplements discussed in this section are available through the Vitamin Depot Online.com Foundation Buyers Club, Inc. For ordering information, call anytime toll-free 1-800-544-4440, or visit us online at www.LifeExtension.com.

The blood tests discussed in this section are available through Life Extension National Diagnostics, Inc. For ordering information, call anytime toll-free 1-800-208-3444, or visit us online at www.LifeExtension.com.