What Is a Bone Density Test and Do You Need One?

When you’re young and healthy, you don’t give much thought to the future of your bones. But if your parents made sure you drank plenty of milk and got daily exercise, your bone health may have been on their mind. 

And that’s good, because when you’re young, your bones are continuously renewing themselves and building up density, and calcium and weight-bearing exercise are two of the keys to keeping this process going.

Around age 25, though, the process slows down. Instead of adding new bone tissue every day, your bones stabilize for several years, neither gaining nor losing bone tissue. Then around age 50 for most people, the process reverses, and you lose more bone tissue than you gain. In other words, the bone breakdown outpaces new bone formation, and leads to a condition called osteoporosis, which leaves your bones vulnerable to fractures. 

Dr. Fayz Yar Khan at Four Peaks Primary Care & Internal Medicine in Phoenix, Arizona, helps you keep a sharp eye on your bone health by offering bone density tests. Here’s what you need to know.

What a bone density test is and isn’t

A bone density test is simply a device that allows us to measure the strength of your bones. Using X-ray technology called a DEXA scan, the device delivers a very low dose of radiation that reveals an image of your bones and lets us know how many grams of calcium are concentrated in a particular area. 

The test is painless and only takes about 20 minutes. We usually take images of the places that can give us the most accurate reading of your bone density, which are also the places that tend to break easily if your bone density is low — your hip, your upper thigh bone, and your forearm. 

Do you need a bone density test?

Women get osteoporosis more often than men, which is why we recommend the test to our female patients over the age of 65 as part of our comprehensive women’s health services, although you may need one sooner if you’re at a high risk for bone loss. Men over 70 may be good candidates for a bone density test as well.

Male or female, regardless of your age, you may need a bone density test if you:

• Drink or smoke heavily
• Have a low body weight
• Have used corticosteroid drugs, such as prednisone, for three months or more
• Have rheumatoid arthritis
• Have lost 1.5 inches or more in height
• Have fractured a bone in a minor accident
• Have had a drop in hormones due to menopause or cancer tretment

Any of these factors can put you at risk for bone loss, which is why we recommend the bone density test if any of them apply to you. It gives us valuable information about the status of your bone health that we can’t determine externally. 

Bone density test results

The results are instant, and give us two numbers to evaluate: a T-score and a Z-score. These numbers tell us how dense your bones are compared to younger, healthy people of your same sex. 

If your T-score is -1 or above, it’s considered normal. If it’s as low as -.25, you may have the early stages of osteoporosis called osteopenia. And any lower than -2.5 is a good indication you have osteoporosis.

Your Z-score compares your bone density to that of people your same age, rather than younger people. It also narrows the comparison population to those of the same weight, sex, and ethnic origin. High or low Z-scores may point to the need for further testing.

If your bone density is low, Dr. Yar Khan may recommend medication to prevent further bone loss. 

How to prevent bone loss

You can maximize your bone density while you’re young and prevent bone loss as you age by:

• Exercising regularly, especially weight-bearing exercises
• Consuming plenty of calcium and vitamin D
• Limiting alcohol consumption and smoking
• Avoiding certain drugs, like corticosteroids and proton pump inhibitors, when possible

To learn more about bone density tests and your risks for osteoporosis, schedule an appointment with Dr. Yar Khan by calling our office or booking online today.