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As an active person who loves to exercise on a daily basis, I value my mobility and physical fitness very much. After a recent injury, I had a conversation with my orthopedic doctor about bone strength and risk of osteoporosis as I grow older. Here I share what I took away from that conversation as well as research on the topic. 

is a chronic disease that causes bones to become weak and prone to breakage. (The word itself means “porous bones.”) 

Bone is a living tissue that constantly is degraded and replenished. Osteoporosis is the condition in which the regeneration of bone tissue does not keep up with the degradation. In severe cases, even mild stresses such as bending down to tie shoelaces or sneezing can cause a fracture. 

, one in three women over the age of 50 years and one in five men will experience osteoporotic fractures in their lifetime. By 2025, that osteoporosis will be responsible for three million fractures resulting in $25.3 billion in costs every year. 

Osteoporosis can be prevented and, after diagnosis, slowed down to decrease the risk of fractures. 

Who is at risk of osteoporosis? 

The International Osteoporosis Foundation describes several factors that contribute to the risk of osteoporosis such as age, sex and hereditary factors. 

Sex: Women are more prone to develop osteoporosis than men. 

Age: The risk for osteoporosis increases as age progresses. 

Race: Individuals of Asian or European descent are more prone to osteoporosis. 

Hereditary factors: Having parents or siblings who have osteoporosis could indicate a greater risk of osteoporosis. 

Body frame: Individuals with a relatively small frame size are at higher risk, as they may not have the bone mass to draw from to replenish the degradation. 

Hormone levels: Lowered levels of sex hormones can lead to osteoporosis. Women who have undergone menopause have a low level of estrogen. Also, treatment of prostate cancer to reduce testosterone or breast cancer treatment to reduce estrogen can lead to increased bone loss. 

Dietary factors: Low calcium intake could lead to reduced bone density. Surgery to reduce stomach size or to remove a section of the intestine could lead to reduced absorption of nutrients. 

Lifestyle choices: Individuals with a sedentary lifestyle may face a higher risk of osteoporosis than those who exercise regularly. Increased consumption of alcohol or tobacco also has been shown to make an individual more susceptible to osteoporosis. 

Diagnosis 

Osteoporosis is known as a silent disease because there are usually no noticeable symptoms.

One way to test bone density is a DEXA scan. DEXA stands for “dual-energy X-ray absorptiometry,” and it is a type of medical imaging test. It uses very low levels of X-rays to measure how dense your bones are.

The National Osteoporosis Foundation recommends people at average risk get a DEXA scan starting at 65 (women) or 70 (men).

The recommends a DEXA scan if you are over the age of 50, have had a broken bone, or have other conditions or have taken medications that put bone health at risk.

Prevention and treatment

Food: About 85-90% of adult bone mass is acquired by age 18 in girls and 20 in boys. Hence, it is essential to focus on nutrition to support building of bone mass from an early age. Having a healthy and varied diet with plenty of fresh fruit, vegetables and whole grains goes a long way toward building and maintaining bone mass. Specific nutrients to focus on according to Harvard School of Public Health are:

Calcium: Some great sources of calcium are dairy and fortified plant-based milks, such as almond, soy and rice milks; cheese; yogurt; calcium-fortified orange juice; winter squash; edamame (young green soybeans); tofu made with calcium sulfate; canned sardines; salmon (with bones); and almonds. According to by a committee of the Institute of Medicine, the recommended daily dietary allowance for calcium for women 19 to 50 years of age is 1,000 mg and for women over 51 is 1,200 mg. For pregnant and lactating women, it is 1,000 mg. For men 19 to 70 years of age, the recommended dietary allowance is 1,000 mg, and for men over 71 it’s 1,200 mg. 

Vitamin D: The body needs vitamin D to absorb calcium. Most people need at least 600 international units a day. That recommendation increases to 800 IU after age 70. Some excellent sources of vitamin D are cod liver oil, salmon, swordfish, tuna, dairy, and orange juice and plant milks fortified with vitamin D.

Lifestyle: Avoiding excessive alcohol consumption, stopping smoking and limiting caffeine intake all delay bone mass degradation.

Exercise: Regular weight-bearing and strength-training activities help build bone mass and slow down bone degradation. Yoga, Pilates, tai chi and other exercise forms that help build balance can reduce the risk of falling and fracture.

Prescription therapies: There are many medications available for those at high risk of osteoporosis and for slowing down the progression of osteoporosis. (such as those advertised under the brand names Boniva and Fosamax) are usually first-line therapies. The monoclonal antibody (commonly known by the brand names Prolia and Xgeva) is an option too.

Recent research

Below are summaries of recent findings about osteoporosis published in the Â鶹´«Ã½É«ÇéƬ and Â鶹´«Ã½É«ÇéƬ Biology’s three open-access journals.

Novel biomarkers could help predict onset of osteoporosis: Bone mineral density, or BMD, is a major risk factor for osteoporosis. Monocytes are a type of white blood cells that circulate in the bloodstream and mature into osteoclasts, which are large multinucleated bone cells that absorb bone tissue during growth and healing. In a in the Journal of Biological Chemistry, scientists explored the expression of genes in circulating monocytes from individuals with high and low BMD. They identified 66 genes that were different between the monocytes in high BMD vs. low BMD individuals. Of those, three genes — namely CCR3 (chemokine receptor 3); HDC (histidine decarboxylase, i.e., the histamine synthesis enzyme); and GCR (glucocorticoid receptor) — previously were known to be involved in bone metabolism and were found to be higher in subjects with lower BMD. These genes could be contributing to development of osteoporosis and could be used as biomarkers to identify hereditary risk factors of osteoporosis.

A new technique to detect estrogen-related osteoporosis in postmenopausal women: Estrogen metabolites play an important role in the development of osteoporosis in post-menopausal women. The sensitivity of existing techniques does not allow for accurate detection of the level of estrogen metabolites in urine. A in the Journal of Lipid Research describes the development of a novel technique based on gas chromatography–mass spectrometry. The high sensitivity and selectivity of this technique allows for the quantification of the estrogen metabolites in urine samples obtained from the postmenopausal women with osteoporosis. This technique can be useful for clinical diagnosis as well as to understand better the pathogenesis of estrogen-related disorders.

Using proteomics to study bone tissue at nanoscale level: Bone tissue is made up of a limited amount of organic material and almost 90% mineralized tissue. Due to the highly variable composition of bone tissue and limited availability of material, analysis of bone tissue is challenging. To study the changes in the bone remodeling process, scientists studied the differences between younger and older bone tissue. This study, in the journal Â鶹´«Ã½É«ÇéƬ & Cellular Proteomics, presented a strategy that allows for in-depth analysis of bone tissue in nanoscale amounts using laser capture microscopy. The researchers’ data showed statistically relevant differences in three proteins (collagen, osteocalcin and osteopontin) between younger and older bone tissue. These results could have important implications in studying bone remodeling, which could help detect osteoporosis.