What is Bone Density? A Complete Guide.

Woman doing squat as part of fitness routine including DEXA scans.

Bone density is a term you might hear when discussing overall health, particularly as you age, but what exactly does it mean? Why is it important to keep track of your bone density, and what can affect it? This guide will explain what bone density is, why it matters for your health, and how it’s measured, including some steps you can take to maintain healthy bones over time.

What is Bone Density?

Bone density, also known as bone mineral density (BMD), refers to the amount of minerals—primarily calcium and phosphorus—present in your bones. These minerals give your bones their strength and structure. Bone density is often used as a measure of bone health, as it reflects the strength of your bones and their ability to withstand stress without breaking.

As you age, it’s common for bone density to decrease, especially in women after menopause. When bone density becomes too low, bones can become weak and brittle, which can lead to fractures or a condition known as osteoporosis .

Why is Bone Density Important?

Bone density is a critical marker of bone health because it directly influences your risk of fractures and other bone-related issues. Bones with higher density are stronger and less likely to break. Bones with lower density, on the other hand, are more porous and fragile, increasing the risk of fractures from minor falls or even everyday movements.

Maintaining good bone density is essential for preserving mobility and independence, especially as we get older. Low bone density is often a precursor to osteoporosis, a condition where bones become so weak that even minor falls can cause serious fractures .

How is Bone Density Measured?

Bone density is commonly measured using a DEXA (dual-energy x-ray absorptiometry) scan. This test is quick, non-invasive, and considered the gold standard for measuring bone density. During a DEXA scan, two x-ray beams with different energy levels are passed through your bones. The amount of x-ray absorbed by the bones is used to calculate your bone density.

Your results from a DEXA scan are typically given as a T-score, which compares your bone density to that of a healthy young adult of the same sex:

  • T-score above -1.0: Normal bone density

  • T-score between -1.0 and -2.5: Low bone density (osteopenia)

  • T-score below -2.5: Osteoporosis

Your bone density can also be expressed as a Z-score, which compares your results to the average bone density of people of your age, sex, and size.

Factors That Affect Bone Density

Several factors can influence your bone density over time:

1. Age

As you age, bone density naturally declines. After about age 30, your body starts to lose bone mass faster than it can be replaced. This is especially true for women after menopause, due to the drop in estrogen levels, which help maintain bone mass .

2. Sex

Women typically have lower bone density than men, and they also tend to lose bone mass more quickly as they age. This makes women more susceptible to osteoporosis, particularly after menopause .

3. Genetics

Your family history plays a role in your bone health. If your parents or grandparents had low bone density or osteoporosis, you may be at higher risk as well .

4. Nutrition

Calcium and vitamin D are essential for maintaining strong bones. Without enough calcium, your body may begin to take calcium from your bones, weakening them over time. Vitamin D is necessary because it helps your body absorb calcium. A diet lacking in these nutrients can lead to lower bone density .

5. Physical Activity

Regular weight-bearing exercises, such as walking, running, and resistance training, help strengthen bones and slow the loss of bone density. A sedentary lifestyle, on the other hand, can accelerate bone loss .

6. Medications

Certain medications, such as long-term corticosteroid use, can affect bone density by decreasing the amount of calcium your bones absorb or by increasing bone loss .

7. Lifestyle Choices

Smoking and excessive alcohol consumption are associated with lower bone density. Both habits can interfere with calcium absorption and reduce bone mass over time .

How to Maintain Healthy Bone Density

Maintaining healthy bone density throughout your life is important for reducing the risk of fractures and osteoporosis. Here are some strategies to help:

1. Get Enough Calcium and Vitamin D

Calcium is crucial for bone health, and you should aim to get enough from your diet or through supplements if needed. And getting enough vitamin D helps your body absorb it effectively.

2. Exercise Regularly

Engage in weight-bearing and strength-training exercises, which are key to maintaining and building bone density. Activities like walking, running, dancing, and resistance training can help stimulate bone formation .

3. Avoid Smoking and Limit Alcohol

Quitting smoking and limiting alcohol intake are both important for preserving bone health. Smoking interferes with calcium absorption, while excessive alcohol can weaken bones and increase the risk of fractures .

4. Monitor Bone Health

If you’re at risk for low bone density or osteoporosis, regular DEXA scans can help you monitor your bone health and track changes over time. Early detection of bone loss allows for interventions to help prevent further deterioration.

Conclusion

Bone density is a key component of your overall health, especially as you age. Monitoring and maintaining healthy bone density can help prevent fractures, osteoporosis, and loss of mobility later in life. Whether through regular DEXA scans, diet, exercise, or lifestyle changes, there are many ways to support strong bones and keep them healthy.

Understanding your bone density is the first step toward preserving your bone health for years to come. If you're concerned about your bone density, talk to your healthcare provider about how to assess your risk and take steps to protect your bones. Get started today by booking a DEXA Scan with Nomad Fit Lab.

Sources:

  1. NIH Osteoporosis and Related Bone Diseases National Resource Center. "Osteoporosis Overview." https://www.niams.nih.gov/health-topics/osteoporosis.

  2. Mayo Clinic. "Osteoporosis." https://www.mayoclinic.org/diseases-conditions/osteoporosis/symptoms-causes/syc-20351968.

  3. American College of Rheumatology. "Bone Density Test." https://www.rheumatology.org/I-Am-A/Patient-Caregiver/Diseases-Conditions/Bone-Density-Test.

  4. National Institutes of Health (NIH). "Menopause and Your Health." https://www.nih.gov.

  5. Office on Women's Health. "Osteoporosis." https://www.womenshealth.gov/a-z-topics/osteoporosis.

  6. National Osteoporosis Foundation. "Are You at Risk?" https://www.nof.org/preventing-fractures/general-facts/are-you-at-risk/.

  7. Harvard School of Public Health. "Calcium and Milk." https://www.hsph.harvard.edu/nutritionsource/calcium-full-story/.

  8. National Institutes of Health (NIH). "Exercise for Your Bone Health." https://www.nih.gov.

  9. Cleveland Clinic. "Corticosteroids and Osteoporosis." https://my.clevelandclinic.org/health/diseases/12486-osteoporosis-in-people-taking-corticosteroids.

  10. National Institutes of Health (NIH). "Bone Health and Smoking." https://www.nih.gov.

  11. Mayo Clinic. "Calcium and Vitamin D." https://www.mayoclinic.org.

  12. American Academy of Orthopaedic Surgeons. "Exercise and Bone Health." https://www.aaos.org.

  13. Centers for Disease Control and Prevention (CDC). "Alcohol Use and Your Health." https://www.cdc.gov/alcohol/about-alcohol-use/index.html

  14. American Lung Association. "The Effects of Smoking on Your Bones." https://www.lung.org.

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