Being female comes with a lot of natural gifts. Unfortunately, it also comes with some physical and hormonal differences that put us at additional risk for breaking bones and developing osteoporosis [1]. Read more about osteoporosis and how to prevent it below.
What is osteoporosis?
Bone is living tissue, and bone cells are not only structural, but they also act as mineral storage for minerals that are used throughout the body for cell signaling. Bone minerals are constantly being broken down so that calcium, phosphorus, magnesium, and potassium can be released into the bloodstream when dietary levels are low. When blood levels are sufficient, excess minerals are stored away in bone again, rebuilding lost mineral density. When dietary levels are not high enough to warrant storage, bone will continue to be broken down, without being rebuilt, as the body prioritizes cell signaling to keep you alive.
Osteoporosis is a disease caused by the breakdown of bones taking place faster than the building of new bone and it is precluded by low bone mass and density. Osteoporotic bones are so weak and brittle that a minor bump or even a strong cough can cause a fracture. There are unlikely to be any symptoms that may warn you of early bone loss before osteoporosis sets in, but your doctor can measure your bone mineral density. Once your bones have been weakened to the point of osteoporosis, you may notice you have lost height, experience back pain from weakened or fractured vertebrae, develop a hunched over posture, or break bones more easily than expected.
About 80% of osteoporosis cases affect women, mostly post-menopause, and it has been estimated that women lose about one-third of the mineral density in their hip bones by the time they reach the age of 80 [1]. Some factors contributing to osteoporosis are genetic while others can be caused by nutrition and lifestyle choices.
Who is most at risk for developing osteoporosis?
Osteoporosis can affect people of any age, any sex, and any race, but there are a few factors that make its development more likely.
Biological Sex
Women generally have smaller skeletons than men when they reach maturity, meaning smaller, thinner bones with less total mineral mass, and therefore less to lose before the bones become brittle. This also means that women with smaller frames are at a higher risk than women of taller, larger stature.
There is also a close relationship between estrogen, the main female reproductive hormone, and maintenance of a functional bone matrix (the structural portion of bone). As women reach menopause their estrogen production drops significantly below baseline, and the cells responsible for balancing bone remodeling and breakdown are no longer triggered by estrogen [2]. The exact mechanism for this relationship has yet to be determined, but the relationship is clear nonetheless. Approximately one in every two women over the age of 50 will break a bone due to osteoporosis [1].
Race
Of all the women in the US, Caucasian and Asian women are at the highest risk of osteoporosis with about 50% likely to develop low bone mass and about 20% to be diagnosed with osteoporosis [1]. Latinas and African-American women are statistically less likely to develop osteoporosis, although it is possible these figures are related to fewer people of color seeking treatment or being treated for these conditions [1].
Age/Family History
There is not a specific age at which all women reach menopause, so the decline in bone density also ranges significantly, but menopause is an appropriate time to start monitoring your bone density and mass with a physician if you have not yet been analyzed. This is especially important if you went through early menopause, have broken a hip or wrist bone, or have a family member with osteoporosis, or low bone mineral density or mass [3].
Nutritional Deficiencies
As low dietary calcium intake can contribute to the development of osteoporosis, those who are lactose intolerant or choose not to consume dairy products may be at greater risk [1]. Vitamin D is also necessary for the absorption of calcium and phosphorus, so both men and women who are vitamin D deficient have an increased risk of bone resorption and diminishing bone mineral density [4]. Vitamin D is made in the body in response to bare skin’s exposure to sunlight and skin cells with more pigment need more time in sunlight to make a healthful level of vitamin D. As we age, we are more likely to spend less time in the sun, but people with darker skin and those who live in cold climates with fewer sunlight hours may need to be especially conscious of their vitamin D levels.
What do my bone density test results mean?
Bone density test results are delivered as a Z-score and a T-score. A T-score compares your bone density to what is normal in a healthy 30-year-old adult (the age at which bone density peaks). T-scores can be objectively used to help diagnose osteoporosis in men over 50 and postmenopausal women.
A Z-score compares your bone density to what is normal for someone your own age. If your Z-score is above -2.0 (ex. +0.5, -0.5, or -1.5), your bone density is considered within the ranges of normal according to the International Society for Clinical Densitometry (ISCD) [1].
If your Z-score is -2.0 or lower (ex. -2.1, -2.3, or -2.5), your bone density is lower than the normal range. This does not mean an automatic osteoporosis diagnosis however. Your doctor may examine your lifestyle, family history, and other health conditions for possible reasons for bone loss other than osteoporosis before giving you a diagnosis. On the flip side, you can still be diagnosed with osteoporosis if your Z-score is normal, but you’ve broken one or more bones from a minor injury.
Is there anything I can do to protect my bones?
Although some of the risk factors are unchangeable, there are multiple ways in which we can protect our bones with diet and lifestyle choices.
Nutrition
Obviously, getting enough calcium and vitamin D is at the top of the list. If you know you aren’t getting much calcium from your diet or spending much time in the sun, ask a trusted healthcare professional about the dose of supplemental calcium and vitamin D you should be taking to mitigate those risk factors. Generally, calcium intake should be 1,200-2000 milligrams per day for women over 50 and men over 70. All adults ages 51 to 70 should get a minimum of 600 international units (IU) a day of vitamin D and 800 IU a day after age 70, although up to 4000 IU of vitamin D per day is safe for most people [3].
Exercise
Although usually associated with muscle building, exercise can help you build strong bones and slow bone loss too [3]. Try to include strength training, weight-bearing, and balance exercises in your routine in order to care for your whole skeleton. Strength training (lifting weights, even light ones) helps to support the bones of your upper body, while weight-bearing exercise (hiking, running, skiing, and many team sports) support your lower back and legs. Balance activities like yoga or tai chi can help you to practice stability and lessen the risk of a fall.
It has also been demonstrated that underweight and overweight bodies are at greater risk of osteoporotic injury [3]. Adding exercise to a healthy diet is a great way to help maintain an appropriate body weight for your frame.
Healthy Lifestyle Choices
Exercise is not only important to build strength, but it is also important to ward off weakening due to a sedentary lifestyle. People who spend too much time sitting are more likely to develop osteoporosis [3].
Just say “no” to smoking and drinking. Excessive alcohol use increases your risk of developing osteoporosis [3]. While smoking tobacco has not yet been tied to osteoporosis directly, it does contribute to the weakening of bones, and so is likely a factor in bone loss and osteoporosis [3].
References
- NOF. “What Women Need to Know”. National Osteoporosis Foundation. Accessed May 28, 2020. https://www.nof.org/preventing-fractures/general-facts/what-women-need-to-know/
- Mikihito Hayashi, Tomoki Nakashima, Noriko Yoshimura, Kazuo Okamoto, Sakae Tanaka, Hiroshi Takayanagi. Autoregulation of Osteocyte Sema3A Orchestrates Estrogen Action and Counteracts Bone Aging. Cell Metabolism, 2019; 29 (3): 627 DOI: 10.1016/j.cmet.2018.12.021
- Mayo Clinic. “Osteoporosis”. Mayo Foundation for Medical Education and Research (MFMER). Accessed May 29, 2020. https://www.mayoclinic.org/diseases-conditions/osteoporosis/symptoms-causes/syc-20351968
- Pop, G. D., et al. “Estimation of 25 (OH) D levels required for maintaining a normal bone turnover in healthy aging men.” Acta Endocrinologica (Buc) 3.1 (2007): 31-43.