What vitamin is good for bones

Osteoporosis is a long-term (chronic) bone disorder that causes your bones to become thin, weak and break easily. In osteoporosis your bones become fragile and fracture (break) easily, especially the bones in your hip, spine, and wrist. Other sites where broken bones occur include the ankle, leg, forearm, upper arm and ribs. These fractures typically occur after a minor trip, fall or similar incident. Your bone is living tissue that is constantly being broken down and replaced. Bones increase in size and mass during periods of growth in childhood and adolescence, reaching peak bone mass around age 30. The greater your peak bone mass, the longer you can delay serious bone loss with increasing age. Peak bone mass is determined largely by genetic factors, with contributions from nutrition, endocrine status, physical activity, and health during growth ¹. Everyone should therefore consume adequate amounts of calcium and vitamin D throughout childhood, adolescence, and early adulthood.

Bone mass in older adults equals the peak bone mass achieved by age 18–25 minus the amount of bone subsequently lost ². Osteoporosis occurs when the creation of new bone doesn’t keep up with the loss of old bone. Broken bones can occur in patients with either osteoporosis or osteopenia (low bone density). Once a fracture occurs the person is considered to be at much higher risk of another fracture. The operational definition of osteoporosis is based on the T-score for bone mineral density (BMD) assessed by dual energy x-ray absorptiometry (DEXA) at the femoral neck or spine and is defined as a value for BMD 2.5 standard deviation (SD) or more below the young female adult mean. World Health Organization (WHO) criteria define a normal T-score value as within 1 standard deviation (SD) of the mean BMD value in a healthy young adult. Secondary osteoporosis is due to the presence of underlying disease or medications, can also lead to low bone mass, resulting in increased risk of fractures ³. Osteoporosis is called a “silent” disease, because you may have bone loss for many years without any symptoms until you break a bone. Osteoporotic fractures can cause severe pain and lead to a significant decrease in quality of life, with increased morbidity, mortality, and disability ⁴. Osteoporotic fracture can make it harder to do daily tasks on your own, such as walking. Over 50 percent of postmenopausal white women will have an osteoporotic-related fracture, and only 33 percent of senior women who have a hip fracture will be able to return to independent living ⁵. In white men, the risk of an osteoporotic fracture is 20 percent, however, the one-year mortality in men who have a hip fracture is twice that of women. Black males and females have a decreased incidence of osteoporosis compared to white, however, those diagnosed with osteoporosis have similar fracture risks ⁵. The aging of the American population is expected to triple the number of osteoporotic fractures ⁶.

Anyone can develop osteoporosis, but it is more common in older women. Osteoporosis is caused by a decrease in bone density, which makes your bones more fragile and easily broken. Everyone’s bones become weaker as they age, but in some people this process happens too quickly. You are more likely to develop osteoporosis if you have risk factors for the disease. Some of the risk factors can be reduced through lifestyle changes or medications but others, such as your age, cannot be changed.

Research has identified common risk factors for developing osteoporosis. Your doctor should investigate these risk factors. This mainly applies to patients 50 years and over but can also apply to younger adults. A bone density scan is the most common test to help diagnose osteoporosis.

Risk factors that cannot be changed include:

• Being over 70 years of age. Your chances of getting osteoporosis increase as you get older.
• Being female. You have a greater chance of getting osteoporosis if you are a woman. Women have smaller bones than men and lose bone faster than men do because of hormone changes that happen after menopause.
• Having fallen in the past
• Your parents having had hip fractures. Having a close family member who has osteoporosis or has broken a bone may also increase your risk.
• Early menopause
• Ethnicity. White women and Asian women are most likely to get osteoporosis. Hispanic women and African American women are also at risk, but less so.

Risk factors that can be reduced include:

• Not being physically active. Not exercising and not being active for long periods of time can increase your chances of getting osteoporosis. Like muscles, bones become stronger and stay stronger with regular exercise.
• Low muscle mass and strength
• Low body weight (BMI below 20kg/m²). Being too thin makes you more likely to get osteoporosis.
• Smoking. Smoking cigarettes can keep your body from using the calcium in your diet. Also, women who smoke go through menopause earlier than those who don’t smoke. These things can increase your risk for osteoporosis.
• High alcohol intake. People who drink a lot are more likely to get osteoporosis.
• Not eating enough energy-rich foods or proteins.
• Getting too little calcium can increase your chances of getting osteoporosis. Not getting enough vitamin D can also increase your risk for the disease. Vitamin D is important because it helps the body use the calcium in your diet.

If you suffer from certain diseases, you are more likely to develop osteoporosis. These include:

• Hypogonadism or early menopause
• Diseases that cause bone loss, such as rheumatoid arthritis
• Hyperthyroidism or hyperparathyroidism
• Chronic liver or kidney disease
• Celiac disease and inflammatory bowel disease
• Cushing’s syndrome
• Certain types of cancer
• HIV/AIDS
• Anorexia nervosa

Some medications can also increase your risk of developing osteoporosis, including:

• Steroids also called glucocorticoids — when used for more than 3 months. Glucocortiocoids are given to people who have arthritis, asthma, and many other diseases.
• Anti-androgen therapy — drugs that block testosterone from working and which are sometimes used to treat prostate cancer
• Aromatase inhibitors — drugs that block oestrogen from being produced and working and which are sometimes used to treat or prevent ovarian or breast cancer
• Thyroid hormone replacement therapy — which can be a risk factor when used for too long
• Antidepressant medications — particularly medicines from the selective serotonin reuptake inhibitors (SSRIs) group
• Proton pump inhibitors (PPIs) — medicines which make your stomach less acidic
• Thiazolidinedione — a medicine sometimes used to treat type 2 diabetes
• Antipsychotic medications — some medicines used in mental illnesses such as schizophrenia
• Anti-epileptic medications — some medicines used to control epilepsy

Osteoporosis is a silent disease. You may not know you have osteoporosis until your symptoms are severe or until you break a bone. Signs and symptoms of osteoporosis include frequent broken bones or fractures, low back pain, loss of height over time or a hunched back. You may get shorter over time due to osteoporosis. The condition can cause your vertebrae (the bones in your spine) to collapse. These problems tend to occur after a lot of bone calcium has already been lost. A bone mineral density (BMD) test is the best way to check your bone health.

You cannot always avoid osteoporosis. However, there are some changes you can make to prevent or reduce your risk. The best way to prevent weak bones is to work on building strong ones. No matter how old you are, it is never too late to start. Building strong bones during childhood and the teen years is one of the best ways to keep from getting osteoporosis later. As you get older, your bones don’t make new bone fast enough to keep up with the bone loss. And after menopause, bone loss happens more quickly. But there are things you can do to slow the natural bone loss with aging and to prevent your bones from becoming weak and brittle. These include getting regular exercise, quitting smoking and getting enough calcium and vitamin D in your diet. They help keep your bones healthy as you age. Dietary supplements can be used as an additional source of calcium and vitamin D if you are not getting enough in your diet.

The plasma calcitriol (1,25-dihydroxyvitamin D or 1,25(OH)2D) or vitamin D concentration depends on the availability of calcidiol (25-hydroxyvitamin D or 25(OH)D) and the activities of the renal enzymes 1-α-hydroxylase and 24-α-hydroxylase ⁷⁶. The renal 1-alpha-hydroxylase enzyme (CYP27B1) is primarily regulated by parathyroid hormone (PTH), serum calcium and phosphate concentrations, and fibroblast growth factor 23 (FGF23) ⁷⁷. Increased parathyroid hormone (PTH), calcitonin, and hypophosphatemia (low blood phosphate) stimulate the renal enzymes 25-hydroxyvitamin D-1-alpha-hydroxylase (CYP27B1) and enhance calcitriol [1,25-dihydroxyvitamin D or 1,25(OH)2D] production, while high calcium, hyperphosphatemia (high blood phosphate) and calcitriol [1,25(OH)2D] inhibit the renal enzymes 1-alpha-hydroxylase (CYP27B1) ⁷⁸. Calcitriol [1,25-dihydroxyvitamin D or 1,25(OH)2D] inhibits the synthesis and secretion of parathyroid hormone (PTH), providing negative feedback regulation of calcitriol production. Calcitriol [1,25-dihydroxyvitamin D or 1,25(OH)2D] synthesis may also be modulated by vitamin D receptors on the cell surface; downregulation of these receptors may play an important role in regulating vitamin D activation ⁷⁹. Fibroblast growth factor 23 (FGF23), a newly described phosphaturic hormone, inhibits renal production of calcitriol [1,25-dihydroxyvitamin D or 1,25(OH)2D] by inhibiting 1-α-hydroxylase in the renal proximal tubule and by simultaneously increasing the expression of 24-α-hydroxylase and production of 24,25(OH)2D (an inactive metabolite) ⁸⁰. Calcitriol [1,25-dihydroxyvitamin D or 1,25(OH)2D] stimulates fibroblast growth factor 23 (FGF23), creating a feedback loop. Fibroblast growth factor 23 (FGF23) decreases renal reabsorption of phosphate, and thereby counteracts the increased gastrointestinal phosphate reabsorption induced by Calcitriol, maintaining phosphate homeostasis ⁸¹.

When hypocalcemia (low blood calcium) occurs, serum parathyroid hormone (PTH) concentration increases and enhances renal tubular reabsorption of calcium, as well as the activity of 1-α-hydroxylase in the kidney. This results in increased Calcitriol [1,25-dihydroxyvitamin D or 1,25(OH)2D] production, and in turn, intestinal calcium absorption. Parathyroid hormone (PTH) also stimulates bone osteoclast activity to mobilize bone calcium stores, thereby increasing serum calcium. Both Calcitriol [1,25-dihydroxyvitamin D or 1,25(OH)2D] and Calcidiol [25-hydroxyvitamin D or 25(OH)D] are degraded in part by being hydroxylated at the 24 position by a 24-hydroxylase. The activity of the 24-hydroxylase gene is increased by calcitriol (which therefore promotes its own inactivation) and reduced by parathyroid hormone (thereby allowing more active hormone to be formed) ⁷⁷. Estrogen, placental growth hormone, and prolactin may also regulate vitamin D metabolism, playing a role during pregnancy to meet increased calcium demands. Calcitriol is also formed in some other tissues, but is used only within the tissues and not circulated. Parathyroid hormone (PTH)- independent extrarenal production of Calcitriol from Calcidiol is by activated macrophages in the lung and lymph nodes. The 1-α-hydroxylase enzyme is also expressed at other extrarenal sites, including the gastrointestinal tract, skin, vasculature, mammary epithelial cells, and in osteoblasts and osteoclasts ⁸².

People can become deficient in vitamin D because they don’t consume enough or absorb enough from food, their exposure to sunlight is limited, or their kidneys cannot convert vitamin D to its active form in the body. In children, vitamin D deficiency causes rickets, a disease where the bones become soft and bend due to a failure of bone tissue to properly mineralize ⁸³. The fortification of milk and other staples, such as breakfast cereals and margarine, with vitamin D beginning in the 1930s has made rickets a rare disease in the United States, although it is still reported periodically, particularly among African American infants and children, immigrants from African, Middle-Eastern, and Asian countries ⁸⁴, ⁸⁵, ⁸⁶. Rickets is also more prevalent among immigrants from Asia, Africa, and the Middle East, possibly because of genetic differences in vitamin D metabolism, dietary preferences, and behavioral differences that lead to less sun exposure ⁸⁷.

Prolonged exclusive breastfeeding without the American Academy of Pediatrics-recommended vitamin D supplementation is a significant cause of rickets, particularly in dark-skinned infants breastfed by mothers who are not vitamin D replete ⁸⁸. Additional causes of rickets include extensive use of sunscreens and placement of children in daycare programs, where they often have less outdoor activity and sun exposure ⁸³, ⁸⁹.

In adults and adolescents, vitamin D deficiency can lead to osteomalacia, in which existing bone is incompletely or defectively mineralized during the remodeling process, resulting in weak bones causing bone pain and muscle weakness ⁹⁰. Signs and symptoms of osteomalacia are similar to those of rickets and include bone deformities and pain, hypocalcemic seizures, tetanic spasms, and dental abnormalities ⁹¹.

A lack of vitamin D has been associated with:

• An impairment in memory and thinking skills in older adults
• Bone, back, or muscle pain
• Cancer (particularly colon cancer)
• Cardiovascular disease, and an increased risk of dying from a stroke or a heart attack
• Constant fatigue and tiredness
• Frequent infections (such as colds and flu)
• Hair loss
• Kidney disease
• Low mood or depression
• Osteomalacia
• Osteoporosis
• Poor dental health
• Rickets
• Severe asthma in children
• Skin wounds that take a long time to heal.

Research also suggests low vitamin D may be a factor in several other conditions such as type 2 diabetes, high blood pressure, and multiple sclerosis.

Vitamin D has other roles in the body, including modulation of cell growth, neuromuscular and immune function, and reduction of inflammation ⁶², ⁸⁴, ⁹². Many genes encoding proteins that regulate cell proliferation, differentiation, and apoptosis are modulated in part by vitamin D ⁶². Many cells have vitamin D receptors, and some convert 25-hydroxyvitamin D (25(OH)D or calcidiol) to calcitriol [1,25-dihydroxyvitamin D or 1,25(OH)2D].

Serum concentration of 25-hydroxyvitamin D (25(OH)D or calcidiol) is the best indicator of vitamin D status. It reflects vitamin D produced cutaneously and that obtained from food and supplements ⁶² and has a fairly long circulating half-life of 15 days ⁹³. 25-hydroxyvitamin D (25(OH)D or calcidiol) functions as a biomarker of exposure, but it is not clear to what extent 25-hydroxyvitamin D (25(OH)D or calcidiol) levels also serve as a biomarker of effect (i.e., relating to health status or outcomes) ⁶². Serum 25-hydroxyvitamin D (25(OH)D or calcidiol) levels do not indicate the amount of vitamin D stored in body tissues.

In contrast to 25-hydroxyvitamin D [25(OH)D or calcidiol], circulating Calcitriol [1,25-dihydroxyvitamin D or 1,25(OH)2D] is generally not a good indicator of vitamin D status because it has a short half-life of 15 hours and serum concentrations are closely regulated by parathyroid hormone, calcium, and phosphate ⁹³. Levels of 1,25(OH)2D do not typically decrease until vitamin D deficiency is severe ⁹⁴, ⁹⁵.

Researchers have not definitively identified serum concentrations of 25-hydroxyvitamin D [25(OH)D] associated with deficiency (e.g., rickets), adequacy for bone health, and overall health. After reviewing data on vitamin D needs, an expert committee of the Food and Nutrition Board at the National Academies of Sciences, Engineering, and Medicine concluded that people are at risk of vitamin D deficiency at serum 25-hydroxyvitamin D [25(OH)D] concentrations less than 30 nmol/L (12 ng/mL; see Table 1 for definitions of “deficiency” and “inadequacy”) ⁶⁷. Some people are potentially at risk of inadequacy at 30 to 50 nmol/L (12–20 ng/mL). Levels of 50 nmol/L (20 ng/mL) or more are sufficient for most people. In contrast, the Endocrine Society stated that, for clinical practice, a serum 25(OH)D concentration of more than 75 nmol/L (30 ng/mL) is necessary to maximize the effect of vitamin D on calcium, bone, and muscle metabolism ⁹⁶. The Food and Nutrition Board committee also noted that serum concentrations greater than 125 nmol/L (50 ng/mL) can be associated with adverse effects (Table 1).

Optimal serum concentrations of 25-hydroxyvitamin D [25(OH)D] for bone and general health have not been established because they are likely to vary by stage of life, by race and ethnicity, and with each physiological measure used ⁹⁷. In addition, although 25-hydroxyvitamin D [25(OH)D] levels rise in response to increased vitamin D intake, the relationship is nonlinear ⁶². The amount of increase varies, for example, by baseline serum levels and duration of supplementation.

An additional complication in assessing vitamin D status is in the actual measurement of 25-hydroxyvitamin D (25(OH)D or calcidiol) concentrations. Considerable variability exists among the various assays available (the two most common methods being antibody based and liquid chromatography based) and among laboratories that conduct the analyses ⁶², ⁹⁸, ⁹⁹. This means that compared with the actual concentration of 25-hydroxyvitamin D (25(OH)D or calcidiol) in a sample of blood serum, a falsely low or falsely high value may be obtained depending on the assay or laboratory used ¹⁰⁰. A standard reference material for 25-hydroxyvitamin D (25(OH)D or calcidiol) became available in July 2009 that permits standardization of values across laboratories and may improve method-related variability ⁶², ¹⁰¹.

Table 5. Serum 25-Hydroxyvitamin D [25(OH)D] Concentrations and Health

Footnotes:

* Serum concentrations of 25(OH)D are reported in both nanomoles per liter (nmol/L) and nanograms per milliliter (ng/mL).
** 1 nmol/L = 0.4 ng/mL and 1 ng/mL = 2.5 nmol/L.

What is a low vitamin D level?

There is a bit of controversy regarding what is considered a low vitamin D level between different expert organizations. A vitamin D level measures levels of 25-hydroxyvitamin D [25(OH)D] also known as calcidiol, in the blood.

Most experts recommend:

• Levels of 20-50 nanograms/milliliter (ng/ml) of 25(OH)D: Sufficient (good)
• Levels of 12-19 ng/ml: Borderline
• Levels of less than 12 ng/ml: Deficient (low)

However, not everybody agrees, and some organizations suggest different cut-off values.

The Institute of Medicine states:

• Levels above 20 ng/ml: Sufficient
• Levels below 20 ng/ml: Deficient

Note that several members of the Institute of Medicine committee publicly stated that over screening for vitamin D deficiency was a problem which typically resulted in unnecessary treatment. They were not in agreement with a cut-off level of 20 ng/ml for deficiency and recommended a lower level of 12.5 ng/ml.

The Endocrine Society states:

• Levels above 30 ng/ml: Sufficient; however, some assays are inaccurate and levels of 40-60 ng/ml better guarantee sufficiency
• Levels of 21-29 ng/ml: Insufficient
• Levels below 20 ng/ml: Deficient

Talk to your doctor about what he/she considers to be a low vitamin D level.

How much vitamin D do you need?

Intake reference values for vitamin D and other nutrients are provided in the Dietary Reference Intakes (DRIs) developed by the Food and Nutrition Board (FNB) at the Institute of Medicine of The National Academies ⁶². DRI is the general term for a set of reference values used to plan and assess nutrient intakes of healthy people. These values, which vary by age and gender, include:

• Recommended Dietary Allowance (RDA): average daily level of intake sufficient to meet the nutrient requirements of nearly all (97%–98%) healthy people.
• Adequate Intake (AI): established when evidence is insufficient to develop an RDA and is set at a level assumed to ensure nutritional adequacy.
• Tolerable Upper Intake Level (UL): maximum daily intake unlikely to cause adverse health effects ⁶².

The Food and Nutrition Board (FNB) established an RDA for vitamin D representing a daily intake that is sufficient to maintain bone health and normal calcium metabolism in healthy people. RDAs for vitamin D are listed in both International Units (IUs) and micrograms (mcg); the biological activity of 40 IU is equal to 1 mcg (Table 5). Even though sunlight may be a major source of vitamin D for some, the vitamin D RDAs are set on the basis of minimal sun exposure ⁶².

Table 5. Recommended Dietary Allowances (RDAs) for Vitamin D

Footnotes: The amount of vitamin D contained in supplements is sometimes expressed in international units (IU) where 40 IU is equal to one microgram (1 mcg) of vitamin D.

The total daily vitamin D intake of persons who are not vitamin D deficient should not exceed 2,000 IU ¹⁰². Many calcium supplements contain vitamin D. Most multivitamins contain 400 IU of vitamin D. Vitamin D supplements can be taken on their own, or with calcium or food.

The upper limit of safety for vitamin D is 4000 IU/day. There are currently differing recommendations regarding the optimal 25-hydroxyvitamin D (25-OHD) level for bone health with the Institute of Medicine committee recommending a 25-hydroxyvitamin D (25-OHD) level ≥20-29 ng/mL while several other societies recommend a 25-OHD level ≥30 ng/mL ⁹⁶.

Adults who are vitamin D deficient require treatment with higher doses of vitamin D, may be treated with 50,000 IU of vitamin D2 or vitamin D3 once a week or the equivalent daily dose (7000 IU vitamin D2 or vitamin D3) for 8–12 weeks to achieve a 25(OH)D blood level of approximately 30 ng/ml ¹⁰³. This regimen should be followed by maintenance therapy of 1500–2000 IU/day or whatever dose is needed to maintain the target blood level ¹⁰⁴, ¹⁰⁵.

Physical Activity for Older Adults

Most elderly individuals should strongly consider engaging in regular physical activity. Physical activity is the only single therapy that can simultaneously improve muscle mass, muscle strength, balance, and bone strength. As a result, it may decrease the risk of fractures, in part by reducing the risk of falling. In fact, fall-risk reduction may be the biggest benefit of physical activity for the elderly.

This summary of a Cochrane review ²⁰⁹ presents what we know from research about the effect of exercise on bone mass in postmenopausal women. The review shows that for postmenopausal women the results suggest a relatively small statistically significant, but possibly important, effect of exercise on bone density compared with control groups. Exercise has the potential to be a safe and effective way to avert bone loss in postmenopausal women.

• Exercise will improve bone mineral density slightly.
• Exercise will reduce the chances of having a fracture slightly.

The following guidelines should be used to maximize the potential fall prevention benefits of physical activity in the elderly:

• Physical activity needs to be of sufficient intensity to improve muscle strength, since poor muscle strength is a known risk factor for falls. Strength or resistance training is best for building muscle, but even aerobic endurance activity can yield some improvements in muscle strength.
• Improving balance can be an important component of any physical activity program designed to decrease falls. This program may include balance training exercises or a movement activity such as Tai Chi. Any activity that requires weight bearing and challenges the postural system can improve balance and potentially help reduce falls.
• Physical activity must be performed on average 3 times per week for 30–45 minutes per session for at least three months for strength and balance benefits to be realized, and it must be continued if benefits are to be maintained.
• Those who suffer a fall that requires a visit to a health care provider or an emergency room should ask for a fall risk assessment that includes a program of physical activity.

Fall Prevention

Falls are not just the result of getting older and falls represent perhaps the biggest threat to the bone health and the functional independence of older individuals. Falls are common and frequently are the precipitating event that leads to a fracture or fractures in an individual. Thus, fall prevention offers another important opportunity to protect the bones throughout life, but particularly in those over age 60. Falls occur for a variety of reasons, with multiple factors often contributing to a single fall. These factors include problems with balance, mobility, vision, lower extremity weakness, and/or blood pressure or circulation. Often these problems are compounded by an acute illness (e.g., infection, fever, dehydration, arrhythmia), a new medication, or an environmental stress (e.g., standing or walking on an unsafe surface, poor lighting) that leads to the fall. To reduce the risk of falls, a variety of fall prevention measures should be encouraged for frail, elderly individuals. These include regular vision checks; elimination (where possible) of medications and/or dosages that may cause dizziness, low blood pressure, or confusion; and addressing environmental problems or obstacles that can lead to falls, including removing throw rugs, installing night lights, installing railings on stairs and grab bars in showers, encouraging use of rubber-soled shoes and slippers, and attaching phone cords and other wires to the baseboard of the wall. Hip protectors or hip pads might also be useful in reducing the impact of those falls that do occur.

Many falls can be prevented. Falls are usually caused by a number of things. By changing some of these things, you can lower your chances of falling:

• Begin a regular exercise program: Exercise is one of the most important ways to reduce your chances of falling. It makes you stronger and helps you feel better. Exercises that improve balance and coordination (like tai chi) are the most helpful. Lack of exercise leads to weakness and increases your chances of falling. Ask your doctor or health care worker about the best type of exercise program for you.
• Have your eyes checked by an eye doctor. You may be wearing the wrong glasses or have a condition such as glaucoma or cataracts that limits your vision. Poor vision can increase your chances of falling.
• Make your home safer: About half of all falls happen at home. To make your home safer:
• Remove things you can trip over (such as papers, books, clothes, and shoes) from stairs and places where you walk.
• Remove small throw rugs or use double-sided tape to keep the rugs from slipping.
• Keep items you use often in cabinets you can reach easily without using a stepstool.
• Have grab bars put in next to your toilet and in the tub or shower.
• Use nonslip mats in the bathtub and on shower floors.
• Improve the lighting in your home. As you get older, you need brighter lights to see well. Lamp shades or frosted bulbs can reduce glare.
• Have handrails and lights put in on all staircases.
• Wear shoes that give good support and have thin nonslip soles. Avoid wearing slippers and athletic shoes with deep treads.

What is osteoporosis?

Osteoporosis literally means “porous bone.” Osteoporosis is a disease of the bones that causes you to lose bone mass. Having osteoporosis raises your risk of experiencing fractures ²¹⁰, ²¹¹. Osteoporosis is characterized by too little bone formation, excessive bone loss, or a combination of both, leading to bone fragility and an increased risk of fractures of the hip, spine and wrist ²¹².

Osteoporosis occurs most often in older adults. Osteoporosis affects men and women of all races. But white and Asian women, especially older women who are past menopause, are at highest risk. This is due to several factors. Women have less bone mass than men to begin with. Women also tend to live longer and absorb less calcium. In women, the rate of bone loss speeds up after menopause, when estrogen levels decrease. Since the ovaries make estrogen, faster bone loss may occur if both ovaries are removed by surgery.

Bone is living tissue that is constantly being broken down and replaced. Normally, bone formation and resorption are closely balanced. Osteoblasts (cells that make the organic matrix of bone and then mineralize bone) and osteoclasts (cells that resorb bone) are regulated by parathyroid hormone (PTH), calcitonin, estrogen, vitamin D, various cytokines, and other local factors such as prostaglandins ²¹³. Osteoporosis occurs when the creation of new bone doesn’t keep up with the loss of old bone.

You may not know you have osteoporosis until your symptoms are severe. There typically are no symptoms in the early stages of bone loss. But once your bones have been weakened by osteoporosis, you might have signs and symptoms of osteoporosis that include:

• Back pain, caused by a fractured or collapsed vertebra
• Loss of height over time
• A stooped posture or a hunched back
• A bone that breaks much more easily than expected

Signs of osteoporosis include frequent broken bones or fractures, low back pain, or a hunched back. You may get shorter over time due to osteoporosis. Osteoporosis can cause your vertebrae (the bones in your spine) to collapse. These problems tend to occur after a lot of bone calcium has already been lost.

The good news is that medications, healthy diet and weight-bearing exercise can help prevent bone loss or strengthen already weak bones.

To diagnose osteoporosis, your doctor will do a bone density scan called a dual energy X-ray absorptiometry (DEXA or DXA) scan. This is a common test that measures your bone density. The DEXA bone scan often checks your hips, spine, and wrist. These are the most common places to have osteoporosis.

The American Academy of Family Physicians does not recommend that doctors use DEXA scans for women younger than 65 or men younger than 70 unless there are risk factors ²¹⁴. The American Academy of Family Physicians recommends that women who are 65 years and older or have an equal or greater fracture risk be screened for osteoporosis ²¹⁴.

What causes osteoporosis?

There are two ways osteoporosis can occur. You can lose too much bone or your body cannot produce enough bone. Some people have both issues. When you’re young, your bones are dense and strong. Osteoporosis makes your bones brittle and breakable.

It is natural to lose some bone mass as you age. For most adults, this begins in their mid 20s. Other factors can increase your risk of osteoporosis. Some of these risk factors are out of your control. For others, you can take steps to reduce your risk. Talk to your doctor about your risk factors.

• Uncontrollable risk factors:
  • Sex: Osteoporosis is more common in women than men.
  • Age: The older you are, the greater your chance of having osteoporosis.
  • Race: Caucasians and Asians are more likely to have osteoporosis.
  • Genetics: Your risk of osteoporosis is higher if it runs in your family.
  • Menopause: This period in a woman’s life causes physical and hormonal effects. For example, it lowers your estrogen. These changes can increase your risk of osteoporosis. Your risk is even higher if you have early menopause (before age 45).
  • Body frame: People who have small, thin frames are more likely to develop osteoporosis.
  • Health: Certain conditions, such as cancer or stroke, can lead to osteoporosis.
• Controllable risk factors:
  • Alcohol abuse
  • Cancer (eg, multiple myeloma)
  • Chronic obstructive pulmonary disease (COPD) (due to the disorder itself, as well as tobacco use and/or treatment with glucocorticoids). Chronic obstructive pulmonary disease is airflow limitation caused by an inflammatory response to inhaled toxins, often cigarette smoke. Alpha-1 antitrypsin deficiency and various occupational exposures are less common causes in nonsmokers.
  • Chronic kidney disease
  • Drugs (eg, glucocorticoids, anticonvulsants, medroxyprogesterone, aromatase inhibitors, rosiglitazone, pioglitazone, thyroid replacement therapy, heparin, ethanol, tobacco)
  • Endocrine disease or hormonal imbalances (eg, glucocorticoid excess, hyperparathyroidism, hyperthyroidism, hypogonadism, hyperprolactinemia, diabetes mellitus)
  • Eating disorders, such as anorexia nervosa
  • Hypercalciuria
  • Hypervitaminosis A
  • Hypophosphatasia
  • Hypovitaminosis D
  • Inactive lifestyle or lack of exercise
  • Lack of calcium and/or vitamins
  • Liver disease
  • Long-term use of certain medicines. Examples include corticosteroids and proton pump inhibitors (PPIs). Corticosteroids treat inflammation, pain, and chronic conditions, such as asthma and rheumatoid arthritis. Proton pump inhibitors (PPIs) help reduce stomach acid. These medicines can make it hard for your body to absorb calcium and cause osteoporosis.
  • Malabsorption syndromes
  • Prolonged weightlessness (as occurs in space flight)
  • Rheumatoid arthritis
  • Smoking or tobacco use.

How do I know if I have osteoporosis?

Osteoporosis does not become clinically apparent until a fracture occurs and so is sometimes referred to as the “silent disease.” Since osteoporosis does not have any symptoms until a bone breaks, it is important to talk to your doctor about your bone health. If your doctor feels that you are at risk for osteoporosis, he or she may order a bone density test. A bone density test measures how strong – or dense – your bones are and whether you have osteoporosis. It can also tell you what your chances are of breaking a bone. Bone density tests are quick, safe, and painless.

Bones affected by osteoporosis may become so fragile that fractures occur spontaneously or as the result of:

• Minor falls, such as a fall from standing height that would not normally cause a break in a healthy bone.
• Normal stresses such as bending, lifting, or even coughing.

Two-thirds of vertebral fractures are painless, although patients may complain of the resulting stooped or hunched posture (kyphosis) and height loss. Typical findings in patients with painful vertebral fractures may include the following:

• The episode of acute pain may follow a fall or minor trauma.
• Pain is localized to a specific, identifiable, vertebral level in the midthoracic to lower thoracic or upper lumbar spine.
• The pain is described variably as sharp, nagging, or dull; movement may exacerbate pain; in some cases, pain radiates to the abdomen.
• Pain is often accompanied by paravertebral muscle spasms exacerbated by activity and decreased by lying supine.
• Patients often remain motionless in bed because of fear of exacerbating the pain.
• Acute pain usually resolves after 4-6 weeks; in the setting of multiple fractures with severe kyphosis, the pain may become chronic.

Patients who have sustained a hip fracture may experience the following:

• Pain in the groin, posterior buttock, anterior thigh, medial thigh, and/or medial knee during weight-bearing or attempted weight-bearing of the involved extremity
• Diminished hip range of motion (ROM), particularly internal rotation and flexion
• External rotation of the involved hip while in the resting position

Figure 2. Common bone fracture areas in osteoporosis

Figure 3. Spine x-rays showing severe compression fractures due to osteoporosis

Footnotes: Spine x-ray imaging as obtained from on DEXA scanner. Normal spine (a); young woman with vertebral deformities (arrows) after post partum osteoporosis (b); severe osteoporosis in 68 year old woman with multiple moderate and severe compression fractures (c)

How is osteoporosis diagnosed?

See your doctor if you have signs of osteoporosis or if it runs in your family. To diagnose osteoporosis, your doctor will do a bone density scan called a dual energy X-ray absorptiometry (DEXA or DXA) scan. This is a common test that measures your bone density. The DEXA bone scan often checks your hips, spine, and wrist. These are the most common places to have osteoporosis.

The American Academy of Family Physicians does not recommend that doctors use DEXA scans for women younger than 65 or men younger than 70 unless there are risk factors ²¹⁴. The American Academy of Family Physicians recommends that women who are 65 years and older or have an equal or greater fracture risk be screened for osteoporosis ²¹⁴.

Bone mineral density (BMD) measurement is recommended in the following patients ²:

• Women age 65 years and older and men age 70 years and older, regardless of clinical risk factors
• Postmenopausal women and men above age 50–69, younger postmenopausal women and women in menopausal transition based on risk factor profile
• Postmenopausal women and men age 50 and older who have had an adult-age fracture, to diagnose and determine the degree of osteoporosis
• Adults with a condition (e.g., rheumatoid arthritis) or taking medication (e.g., glucocorticoids in a daily dose ≥5 mg prednisone or equivalent for ≥3 months) associated with low bone mass or bone loss

Baseline laboratory studies include the following:

• Complete blood count: May reveal anemia
• Serum chemistry levels: Usually normal in persons with primary osteoporosis
• Liver function tests
• Thyroid-stimulating hormone (TSH) level: Thyroid dysfunction has been associated with osteoporosis
• 25-Hydroxyvitamin D [25(OH)D] level: Vitamin D insufficiency can predispose to osteoporosis
• Serum protein electrophoresis: Multiple myeloma may be associated with osteoporosis
• 24-hour urine calcium/creatinine: Hypercalciuria may be associated with osteoporosis; further investigation with measurement of intact parathyroid hormone (PTH) and urine pH may be indicated; hypocalciuria may indicate malabsorption, which should be further evaluated with a serum vitamin D measurement and consideration of testing for malabsorption syndromes such as celiac sprue
• Testosterone (total and/or free) and luteinizing hormone (LH)/follicle-stimulating hormone (FSH): Male hypogonadism is associated with osteoporosis

Bone density scan

Bone density scan also called bone densitometry, dual-energy x-ray absorptiometry, DEXA or DXA, uses a very small dose of ionizing radiation to produce pictures of the inside of your body (usually the lower lumbar spine and hips) to measure bone mineral density (BMD) or bone loss.

DEXA scan is most often used to diagnose osteoporosis, to assess an individual’s risk for developing osteoporotic fractures. DEXA is also effective in tracking the effects of treatment for osteoporosis and other conditions that cause bone loss.

The DEXA bone scan can also assess an individual’s risk for developing fractures. The risk of fracture is affected by age, body weight, history of prior fracture, family history of osteoporotic fractures and life style issues such as cigarette smoking and excessive alcohol consumption. These factors are taken into consideration when deciding if a patient needs therapy.

DEXA scan is simple, quick and noninvasive. It’s also the most commonly used and the most standard method for diagnosing osteoporosis. The DEXA bone density test is usually completed within 10 to 30 minutes, depending on the equipment used and the parts of the body being examined.

Bone density testing is strongly recommended if you ²¹⁷:

• are a post-menopausal woman and not taking estrogen.
• have a personal or maternal history of hip fracture or smoking.
• are a post-menopausal woman who is tall (over 5 feet 7 inches) or thin (less than 125 pounds).
• are a man with clinical conditions associated with bone loss, such as rheumatoid arthritis, chronic kidney disease or liver disease.
• use medications that are known to cause bone loss, including corticosteroids such as Prednisone, various anti-seizure medications such as Dilantin and certain barbiturates, or high-dose thyroid replacement drugs.
• have type 1 diabetes, liver disease, kidney disease or a family history of osteoporosis.
• have high bone turnover, which shows up in the form of excessive collagen in urine samples.
• have a thyroid condition, such as hyperthyroidism (overactive thyroid).
• have a parathyroid condition, such as hyperparathyroidism.
• have experienced a fracture after only mild trauma.
• have had x-ray evidence of vertebral fracture or other signs of osteoporosis.

An additional procedure called Vertebral Fracture Assessment (VFA) is now being done at many centers. The Vertebral Fracture Assessment (VFA) is a low-dose x-ray examination of the spine to screen for vertebral fractures that is performed on the DEXA machine, may be recommended for older patients, especially if:

• they have lost more than an inch of height.
• have unexplained back pain.
• if a DEXA scan gives borderline readings.
• the DEXA images of the spine suggest a vertebral deformity or fracture.

The VFA test adds only a few minutes to the DEXA procedure.

The dual-energy x-ray absorptiometry (DEXA) scan requires little to no special preparation. You will probably be asked to fill out a questionnaire that will help the doctor determine if you have medical conditions or take certain medications that either increase or decrease your risk of a fracture.

Tell your doctor and the technologist if there is a possibility you are pregnant or if you recently had a barium exam or received an injection of contrast material for a CT or radioisotope scan. Leave jewelry at home and wear loose, comfortable clothing. You may be asked to wear a gown. You should not take calcium supplements for at least 24 hours before your exam.

DEXA scan results

A radiologist, a doctor trained to supervise and interpret radiology examinations, will analyze your dual-energy x-ray absorptiometry (DEXA) scan images. The radiologist will send a signed report to your primary care or referring physician who will discuss the results with you.

Dual-energy x-ray absorptiometry (DEXA) scans are also interpreted by other physicians such as rheumatologists and endocrinologists.

Your DEXA test results will be in the form of two scores:

• T score: This number shows the amount of bone you have compared with a young adult of the same gender with peak bone mass. A T-score of -1 (minus 1) and above is considered normal. A T-score between -1.1 and -2.4 is classified as osteopenia (low bone mass). A T-score of -2.5 and below is defined as osteoporosis. The T-score is used to estimate your risk of developing a fracture and also to determine if treatment is required.
• Z score: This number reflects the amount of bone you have compared with other people in your age group and of the same size and gender. If your Z-score is unusually high or low, it may indicate a need for further medical tests.

Small changes may normally be observed between scans due to differences in positioning and usually are not significant.

What are the limitations of a bone density scan?

• A DEXA test cannot predict who will experience a fracture but can provide a relative risk and it is used to determine whether treatment is required.
• Despite its effectiveness as a method of measuring bone density, DEXA is of limited use in people with a spinal deformity or those who have had previous spinal surgery. The presence of vertebral compression fractures or osteoarthritis may interfere with the accuracy of the test; in such instances, CT scans may be more useful.
• Central DEXA devices are more sensitive and better standardized than peripheral DEXA devices but they are also somewhat more expensive.
  • In the central DEXA examination, which measures bone density of the hip and spine, the patient lies on a padded table. An x-ray generator is located below the patient and an imaging device, or detector, is positioned above. To assess the spine, the patient’s legs are supported on a padded box to flatten the pelvis and lower (lumbar) spine. To assess the hip, the patient’s foot is placed in a brace that rotates the hip inward. In both cases, the detector is slowly passed over the area, generating images on a computer monitor. You must hold very still and may need to hold your breath for a few seconds while the technologist takes the x-ray. This helps reduce the possibility of a blurred image. The technologist will walk behind a wall or into the next room to activate the x-ray machine.
  • In the peripheral DEXA scan, the finger, hand, forearm or foot is placed in a small device that obtains a bone density reading within a few minutes.
• A test done on a peripheral location, such as the heel or wrist, may help predict the risk of fracture in the spine or hip. These tests are not as helpful in following response to treatment, however, and if they indicate that drug therapy is needed, a baseline central DEXA scan should be obtained.
• Follow-up DEXA exams should be performed at the same institution and ideally with the same machine. Bone density measurements obtained with different DXA equipment cannot be directly compared.

Osteoporosis treatment

Treatment for osteoporosis starts with changes to your diet and lifestyle. You need to get enough calcium and vitamin D. Your doctor will want you to increase your physical activity. This helps to strengthen your bones and increase your bone mass. Examples of weight-bearing exercises include walking, jogging, and climbing steps. You also should stop smoking and limit alcohol.

If you’re at risk for falls, reduce your risk by getting rid of tripping hazards in your home. For example, remove rugs, avoid slick surfaces, and move electrical cords. You can install grab bars in certain places, such as your bathroom and shower. The bars can help you move around more easily and safely.

Maintaining a healthy weight can also help you manage osteoporosis. Stopping smoking and reducing your alcoholic consumption to just 2 standard drinks a day can improve your bone strength.

Treatment recommendations are often based on an estimate of your risk of breaking a bone in the next 10 years using information such as the bone density test. If your risk isn’t high, treatment might not include medication and might just focus instead on modifying risk factors for bone loss and falls.

Your doctor may prescribe medicine(s) to help treat osteoporosis. There are several types and forms.

• Biophosphonates. For both men and women at increased risk of fracture, the most widely prescribed osteoporosis medications are bisphosphonates. Biophosphonates help reduce your risk of breaks and fractures. It also increases bone density. It comes in oral (pill) form or intravenous (IV or injection) form. Side effects can include nausea, abdominal pain and heartburn-like symptoms. You may have irritation of the esophagus (the tube that connects your mouth and stomach). These are less likely to occur if the medicine is taken properly. Some people cannot take biophosphonates. This includes people who have kidney disease or low levels of calcium in their blood, and women who are pregnant or nursing. Examples of biophosphonates include:
  • Alendronate (Binosto, Fosamax): This medicine is used to help prevent and treat osteoporosis. They help reduce your risk of fractures by decreasing the rate of bone loss. They are available in pill form. Their most common side effect is an upset stomach.
  • Risedronate (Actonel, Atelvia): This medicine is used to help prevent and treat osteoporosis. They help reduce your risk of fractures by decreasing the rate of bone loss. They are available in pill form. Their most common side effect is an upset stomach.
  • Ibandronate (Boniva): This medicine helps to slow bone loss and increase bone density. It is available as a pill or injection. You have 2 options for the pill. You can take it daily or monthly. For the injection, your doctor or nurse will give you a shot every 3 months. Side effects may include lower back or side pain, shortness of breath, tightness in your chest, and bloody or cloudy urine.
  • Zoledronic acid (Reclast, Zometa). This medicine is given through IV once a year. Intravenous forms of bisphosphonates don’t cause stomach upset but can cause fever, headache and muscle aches for up to three days. It might be easier to schedule a quarterly or yearly injection than to remember to take a weekly or monthly pill, but it can be more costly to do so.
• Hormone-related therapy:
  • Estrogen, especially when started soon after menopause, can help maintain bone density. However, estrogen therapy can increase the risk of blood clots, endometrial cancer, breast cancer and possibly heart disease. Therefore, estrogen is typically used for bone health in younger women or in women whose menopausal symptoms also require treatment.
  • Raloxifene (Evista) is not a hormone, but it mimics estrogen’s beneficial effects on bone density in postmenopausal women, without some of the risks associated with estrogen. Taking this drug can reduce the risk of some types of breast cancer. Hot flashes are a common side effect. Raloxifene also may increase your risk of blood clots.
  • In men, osteoporosis might be linked with a gradual age-related decline in testosterone levels. Testosterone replacement therapy can help improve symptoms of low testosterone, but osteoporosis medications have been better studied in men to treat osteoporosis and thus are recommended alone or in addition to testosterone.
• Bone-building medications: If you can’t tolerate the more common treatments for osteoporosis — or if they don’t work well enough — your doctor might suggest trying:
  • Teriparatide (Forteo) is a synthetic form of parathyroid hormone (PTH) and it stimulates new bone growth. This medicine helps prevent and treat osteoporosis in women. It’s given by daily injection under the skin. You inject it in your thigh or stomach once a day. After two years of treatment with teriparatide, another osteoporosis drug is taken to maintain the new bone growth. Common side effects are nausea, stomach pain, headache, muscle weakness, fatigue, and loss of appetite.
  • Abaloparatide (Tymlos) is another drug similar to parathyroid hormone. You can take it for only two years, which will be followed by another osteoporosis medication.
  • Romosozumab (Evenity). This is the newest bone-building medication to treat osteoporosis. It is given as an injection every month at your doctor’s office. It is limited to one year of treatment, followed by other osteoporosis medications.
  • Calcitonin. This is a hormone that helps slow down bone loss. It is available as an injection or nasal spray. Side effects of the injection include diarrhea, stomach pain, nausea, and vomiting. Side effects of the nose spray include headache and irritation of your nose lining.
• Monoclonal antibody medications: This drug is used when other drugs don’t work or if you can’t tolerate other treatment options. Denosumab (Prolia, Xgeva) increases your bone density. Compared with bisphosphonates, Denosumab produces similar or better bone density results and reduces the chance of all types of fractures. Denosumab is delivered via a shot under the skin every six months. It can be used by both women and men.  Side effects can include lower calcium levels, skin rash, or pain in the arms and legs. If you take denosumab, you might have to continue to do so indefinitely. Recent research indicates there could be a high risk of spinal column fractures after stopping the drug.
  • A very rare complication of bisphosphonates and denosumab is a break or crack in the middle of the thighbone.
  • A second rare complication is delayed healing of the jawbone (osteonecrosis of the jaw). This can occur after an invasive dental procedure such as removing a tooth.

You should have a dental examination before starting these medications, and you should continue to take good care of your teeth and see your dentist regularly while on them. Make sure your dentist knows that you’re taking these medications.

Exercise

Exercise is an important part of an osteoporosis treatment program. Exercise can strengthen your bones and muscles and decrease your risk of falling. Research shows that the best physical activities for bone health include strength training or resistance training, like lifting weights and weight bearing exercises (exercise done while on your feet so you bear your own weight) like brisk walking, jogging, tennis or volleyball. Because bone is living tissue, during childhood and adulthood, exercise can make bones stronger. However, for older adults, exercise no longer increases bone mass. Instead, regular exercise can help older adults:

• Build muscle mass and strength and improve coordination and balance. This can help lower your chance of falling.
• Improve daily function and delay loss of independence.

An exercise program for osteoporosis should include four components:

1. Weight-bearing exercises force your body to work against gravity, which helps to strengthen bones. Examples include walking, climbing stairs, playing tennis, and dancing. Higher-impact activities strengthen bone more than lower-impact exercises, but only do what your fitness level allows.
2. Muscle-strengthening exercises use weights or your body’s own resistance to work against gravity. Examples include lifting free weights, using a weight machine, working with resistance bands, and lifting your own body weight. Do these types of exercises at least twice a week.
3. Balance exercises improve your ability to hold yourself upright and help prevent falls. Examples include tai chi and yoga. Perform balance exercises at least twice a week.
4. Flexibility exercises keep your muscles limber and joints mobile. They include yoga and stretching. Try to stretch for at least five to 10 minutes after every workout. Hold each stretch for 10 to 30 seconds.

Exercises that help improve your balance are useful to help avoid falling over in the future. Examples of some exercises that can help you improve your balance are:

• Tai Chi
• standing with your feet close together
• standing on one leg
• walking backwards

Reducing your likelihood of falling is also important. Consider how you might arrange your home and workplace so you are less likely to trip — for example by fixing down rugs and keeping the floor clear. Wearing sensible shoes and glasses if you need them can also help to keep you stable as your move around.

Although exercise is beneficial for people with osteoporosis, it should not put any sudden or excessive strain on your bones. If you have osteoporosis, you should avoid high-impact exercise. Your doctor or physiotherapist can help you build a safe exercise plan which suits your needs and reduces your risk of fracturing your bones. To help prevent injury and fractures, a physical therapist or rehabilitation medicine specialist can:

• Recommend specific exercises to strengthen and support your back.
• Teach you safe ways of moving and carrying out daily activities.
• Recommend an exercise program that is tailored to your circumstances.

Exercise specialists, such as exercise physiologists, may also help you develop a safe and effective exercise program.

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