"I Don't Get What The Doctor Told Me..." The Vocabulary Of Osteoporosis

Bone mineral density test, a.k.a. bone density test, DEXA-scan, densitometry scan, DXA-scan, bone mass density test: This test uses X-rays to figure out how many grams of calcium and other minerals are packed into a specific quantity of bone. The test doesn’t look at all your bones; it focuses on those most likely to break as your bones thin: your lower spine, hip, and forearm/wrist. It’s non-invasive (i.e., you don’t have to drink anything or be injected with anything beforehand). You lie out in the open; the machine never touches you. And the whole thing takes about 10 minutes. All in all, it’s a really easy test.

And once you have the results of your first bone density test, it’s like having your first mammogram results: the doctor will use it as a baseline, to track whether/how fast your bones are thinning. Typically, the baseline test is followed by tests every other year. The tests may be done every year if there’s strong evidence your bones are thinning pretty quickly, and/or if you’re trying different things to stop osteopenia from turning into osteoporosis.

T-score: This is the number you get from the bone density test. It compares your bones to a healthy young adult of the same sex, and then gives you a score. Zero is the healthy young adult score. Anything above –1 SD (minus 1 standard deviation–don’t worry, you don’t have to understand the statistical math here) is considered normal. From –1.0 to –2.5, you’ve got osteopenia. Below –2.5, you’ve got osteoporosis. And by the way, these figures refer to postmenopausal women. If you fall into another group, figures may vary, as they say.

Calcium: What IS that stuff that’s supposed to pack your bones? The reason your mom made you drink all that milk? Well, it’s the most abundant mineral in the human body. And 99% of it is stored in your bones, including your teeth. But the tiny little bit that circulates in your bloodstream helps your nerves send messages, your muscles work, your heart beat—calcium literally keeps you alive.

Your bloodstream will always get the calcium it needs, by drawing it from your bones; the problem is that if there’s not enough calcium in your diet, or your bones are shedding their calcium more quickly than you can replace it, then there’s not enough to go around. Uh-oh… here comes osteoporosis. See why you take those calcium tablets every day?

Vitamin D: Calcium’s best friend. Vitamin D helps your body absorb and metabolize calcium (in simple terms, put it to use). Without sufficient levels of Vitamin D (and that’s Vitamin D3, specifically), you can stop worrying about your calcium intake; it won’t make any difference. You need Vitamin D just as much as you need calcium.

Vitamin D can come from your food (usually, eggs and fortified dairy products); in tablet form; or mainly, from exposure to the sun. In many parts of the country, your normal routine will give you sufficient outdoor time for your body to make all the vitamin D it needs. In northern climates (say, anywhere north of Boston in the winter), you simply won’t get enough D from sunlight, and you’ll need to go the supplement route.