When you think about protecting your body and health as you age, one of the top factors should be keeping your bones strong. The more you know about bone density and what can affect it, the better you can take steps to reduce the risk of osteoporosis. The many factors that influence your bones, from nutrition to exercise, and hormones to digestion, play a significant role in keeping them working in top form.
Bone density lets us know the strength of the bones and how likely they are to break as we age. It identifies if we are at risk of developing osteopenia or osteoporosis. Osteopenia is the early stage of losing bone mass, when the bones become weaker but not to the point where they break easily, as with osteoporosis. Taking steps early to protect your bones against these conditions is crucial.
It is easy to take bone density and bone health for granted while we are young. Calcium intake plays a significant role throughout life in affecting bone density, as calcium is a mineral, as is phosphorous, and together, these minerals make up approximately 65% of bone tissue. Without enough calcium and phosphorous, the bones lose their rigidity and hardness.
It is time to examine the factors that affect your bone density, why maintaining it as you age is essential, and what steps you can take to strengthen your bones.
Why Is Bone Density Important?
Bones do more for the body than many people realize, including protecting the internal organs from damage, serving as anchors for the muscles, fat storage, and helping produce red blood cells (in bone marrow). Maintaining bone density is crucial for movement, endocrine regulation, and storage of ions. One of the most important reasons to maintain bone mineral density is to store calcium.
Calcium is the body’s most abundant mineral, with calcium ions used for the following functions:
- Heart rate and contraction strength regulation
- Tooth health
- Nerve impulse conduction
- Skeletal and smooth muscle cell contraction
- Blood coagulation
Bones undergo a continual cycle of renewal in a process called bone remodeling. Many factors influence this process, helping old bone cells die and forming new bone cells. By age thirty, most people attain maximum bone mass, but as remodeling continues, bone mass decreases.
Bone turnover takes about four to five months as old bone cell resorption triggers the formation of new bone by osteoblasts (bone-forming cells). Osteoclasts (bone-degrading cells) excavate the old bone cells that release calcium that eventually enters the bloodstream. Osteocytes are the most common bone cell, maintaining mineral concentrations.
Inside the bones, connective tissue called bone marrow performs crucial tasks. Yellow bone marrow contains adipose tissue housing triglycerides (a vital energy source) stored in the adipocytes. In the red bone marrow, a process called hematopoiesis, stimulated partly by testosterone, supports the production of blood cells. Reduced bone density can lead to anemia if not enough red blood cells are produced by red marrow.
What Can Affect Bone Density?
The old rhyme song about various bones being connected to other bones does not account for the muscles, cartilage, tendons, blood vessels, and everything else that supports the skeletal system. Yes, the foot bone is connected to the ankle bone, which is connected to the leg bone, and so on, but without proper nutrition, vital hormones, and exercise, those bones can lose their density and become weak.
The body’s systems depend on one another to keep it healthy. Illness, injury, bad habits, lifestyle choices, medications, hormonal decline, and other issues can affect bone density.
- Here are some of the leading factors that can reduce bone density:
- Bad habits, such as smoking or excessive alcohol intake
Smoking and heavy alcohol use have been shown to reduce bone mass and increase the risk of fractures. Cadmium and nicotine in cigarettes can lower calcium absorption and alter estrogen metabolism. Alcohol inhibits bone remodeling and increases magnesium and calcium loss.
- Sedentary lifestyle:
Exercise plays a significant factor in keeping bones strong. A sedentary lifestyle causes the bones to lose collagen fibers and mineral salts. Bones undergo remodeling based on the forces placed on them. Lack of exercise reduces the force on the bones. Resistance training places the most significant force on the bones to help slow down bone loss and increase bone mass. Physical activity can also help reduce the risk of injury and falling.
An important note about physical activity is that it only affects areas of the body associated with exercise. Lifting weights with the arms will not improve bone density in the legs. Whole-body workouts are crucial.
- Aging
Bone turnover naturally slows down with age. A hormonal decline can further speed that process, as can the other factors listed here. Taking steps to improve bone mineral density can help.
- Some medical conditions
- Genetic diseases such as muscular dystrophy and cystic fibrosis
- Gastrointestinal diseases such as Crohn’s disease, celiac disease, primary biliary cirrhosis, intestinal malabsorption
- Endocrine disorders such as Cushing’s syndrome, diabetes, hyperparathyroidism
- Blood disorders such as leukemia, multiple myeloma, hereditary anemia
- Lupus
- Rheumatoid arthritis
- Ovarian failure
- Depression
- Low body weight/extremely thin
- Some medications
Some of the medications that can affect bone density and skeletal health include:
- Corticosteroids
- Gonadotrophin-releasing hormone agonists
- Anticonvulsant or antiseizure medications
- Too much thyroid hormone medication
- Low levels of vitamins and minerals
Calcium, vitamin D, vitamin K, magnesium, fluoride, and omega-3 fatty acids, are some of the vitamins and minerals required by the body to keep bones strong. Vitamin D is necessary for calcium absorption. Calcium is essential to make calcium carbonate and calcium phosphate that provide hardness to the bones. Vitamin K helps with bone mineralization. Magnesium and fluoride are structural components of bone. Omega-3 fatty acids help to reduce inflammation in the body, which can interfere with osteoblast functions.
Calcium must come from outside sources since the body cannot make it. However, without vitamin D, the body cannot absorb calcium from the small intestine. Good sources of calcium include dairy, leafy green vegetables, salmon, sardines (with bones), nuts, broccoli, seeds, beans, and shellfish. Vitamin D is only found in a few foods, like fatty fish, fortified cereal, and milk. Sunlight is the best source of vitamin D. Supplements are available when necessary.
Additional minerals and vitamins that help promote healthy bones are phosphorus, vitamin C, zinc, copper, iron, potassium, and manganese. Sodium can increase bone loss, so avoiding a diet high in sodium is beneficial. Increasing fruit and vegetable consumption is beneficial for the bones.
Blood testing can tell you if you are low in any essential vitamins and minerals.
- Hormone changes
Several hormones are involved in regulating bone growth, maintaining bone matrix, and supporting bone remodeling:
- Human growth hormone (HGH): as a primary regulator of cellular regeneration, HGH stimulates the production of various types of blood cells. It also increases calcium retention to improve bone density.
- Insulin growth factor 1 (IGF-1): after its release from the liver via HGH stimulation, IGF-1 mediates many of the cell-regenerating effects of HGH in the body.
- Parathyroid hormone: assists osteoclast bone resorption and proliferation, calcium absorption in the small intestine, and calcium reabsorption by the kidneys.
- Calcitriol: stimulates phosphate and calcium absorption from the digestive tract.
- Calcitonin: stimulates skeletal calcium uptake and inhibits osteoclast activity.
- Thyroxine: this thyroid hormone promotes osteoblast activity and bone matrix synthesis.
- Testosterone: the androgen hormone testosterone plays numerous roles in maintaining healthy bones. It has a direct influence on osteoblasts to promote bone formation. Testosterone also acts indirectly by converting into estradiol (estrogen) and dihydrotestosterone (DHT), which also influence bone density. Both testosterone and estrogen affect osteoblasts and osteoclasts.
Does testosterone increase bone density, or is it just a myth?
Testosterone replacement therapy, for those with low testosterone, can have benefits for improving bone density. As with any hormone, only those who need it should use that treatment. Hormone replacement provides many additional benefits to those who suffer from hormone deficiency. Contacting a hormone specialist is always a good idea for adults over thirty with concerns about their hormone levels.
Who Should Get a Bone Density Test?
Bone density tests measure calcium and other vital minerals in the bones. These low-dose X-rays use a small area, such as the spine, hips, femur, or wrist, to determine your risk factor. You may receive scanning at all 4 sites for accuracy.
Bone density testing is recommended for young people with any of the previously mentioned risk factors for medical conditions or medication use, as they may be more susceptible to weakened bones.
Because the osteoporosis risk increases with age, women over 65 should undergo bone density testing. Menopausal age women with risk factors or postmenopausal women under 65 with risk factors should also be tested. Testing may be suggested sooner if there is a family history of osteoporosis or fractures.
You may be able to wait up to 15 years between screenings if you have normal bone density. However, those receiving treatment should undergo testing every two years unless a different schedule is recommended.
Men over 70 should be tested regularly. Those in the 50 to 69 age group should also get tested if they have any of the factors mentioned in the previous section.
With bone density testing, a T score measures postmenopausal women and men 50 and older against healthy 30-year-old adults. A Z score measures premenopausal women and men under 50 against people of their gender and age.
Here are some other ways of knowing if you should get a bone density test:
- People over 50 who have suffered a broken bone
- If you have lost more than 1.5 inches of height in total or ½ inch or more in one year
- If you have unexplained back aches
- If your posture is getting worse
- If your parent experienced a hip fracture
- If your hormone levels have dropped
- If doing sports or exercise brings pain
Conclusion
Protecting your bones as you age is one of the best things you can do for your body. Regular exercise, including weight-bearing exercises, walking, swimming, stair climbing, or running, is crucial. Avoiding cigarette smoking and excessive alcohol consumption (more than two drinks daily) can help lower your risk of osteoporosis. Eating a healthy diet and getting enough vitamins and minerals is crucial.
Blood hormone and vitamin levels testing can help uncover problems you may not realize are present.
Speak to your doctor about bone density testing if you have any concerns. Catching any problems early can make a significant difference.
