In this edition of Hot Flashes, we’re going to look at maintaining skeletal health. First, what is osteoporosis? For many people, this term conjures up an image of a stooped-over elderly woman with the classic Dowager’s hump—the definitive sign of osteoporosis. For others, it brings to mind a broken hip or spinal fractures and progressive debility.

Contrary to the impression that the skeleton is a hard, static structure, in reality, bone is dynamic, living tissue. Bony tissue is actually a matrix composed largely of collagen fibers and mineral salts, such as calcium and phosphorous.

If you’ve read anything about nutrition, chances are you’re familiar with the role calcium plays in bone health. But other minerals are key to keeping your bones strong, including boron, magnesium, copper, manganese and zinc. While needed in much smaller quantities than calcium, these minerals are vital to healthy functioning of skeletal tissue.

Throughout your life, new bone is continually being formed, while old bone is removed. Up until about age 30, the addition portion of this equation predominates as your bones continue to grow, becoming larger and denser. After 30, the balance starts to shift, and now more old bone is reabsorbed than new bone is formed.

As this process progresses, the network of collagen and minerals becomes more and more porous, making bones weaker and weaker. If the bone becomes porous enough, you have osteoporosis.

When women hit menopause, bone loss increases even more, probably as a result of decreasing levels of estrogen. While the mechanism is not entirely clear, estrogen is believed to protect bones by stimulating the cells that produce new bone and inhibiting the cells that reabsorb old bone.

Diagnosing Osteoporosis

The World Health Organization (WHO) has established specific criteria for the diagnosis of osteoporosis and it’s determined based on a measure called, bone mineral density (BMD). BMD measures the amount of minerals in your bones, and gauges how strong they are.

According to WHO’s criteria, you aren’t diagnosed with osteoporosis until your BMD is a specified amount lower than that of an average Caucasian 25-year-old woman. However, you can have low bone density without having full-blown osteoporosis. This condition is termed osteopenia, which simply means a decrease (-penia) in bone (osteo-). Most tests also provide an age-matched reading based on what density is expected for someone of your age, weight and sex.

Bone density can be measured centrally in the hip or spine or peripherally (usually at the heel, shin, knee, wrist, or finger). The most common way to measure bone density—and the one considered the “gold standard” —is called DEXA, which stands for Dual Energy X-ray Absorptiometry. This method uses an x-ray beam with two different energy peaks. Soft tissue absorbs one peak and bone absorbs the other. When the soft tissue measure is subtracted, you’re left with the amount that tells your bone density. SXA—or Single Energy X-ray Absorptiometry—is used at peripheral sites, such as the wrist or heel. Other ways to measure bone density include ultrasound, computer tomography, and dual and single photon absorptiometry. A standard conventional x-ray typically is not a good way to determine bone density.