Your bones – all 206 of them – are living, growing tissues that form a head-to-toe supportive framework for your body. They also protect vital organs, anchor your muscles, and store calcium. Given their important role in your body, it is critical that you understand how to promote and preserve bone health throughout your life.
Your Bone “Bank Account”
Bones begin to develop before birth, but the formation process is not complete until about 20 to 30 years of age. Even then, bone is constantly renewed through a process called remodeling, during which new bone tissue is laid down to replace the old.
In children and teens, new bone is formed faster than old bone is removed, and over time, the bone gradually gets larger, heavier, and more dense. Most people achieve peak bone mass by the time they turn 30, after which they lose slightly more bone mass than they gain through remodeling.
At some point in your adult life, your primary care provider (PCP) may order a test called a dual-energy x-ray absorptiometry, or DEXA scan, to measure your bone density. The DEXA scan can help predict your risk for fractures and detect evidence of osteoporosis. The likelihood of developing osteoporosis – a condition in which bones become weak and brittle and prone to fracturing – depends on how much bone mass you are able to “bank” by age 30, as well as how rapidly you lose bone mass after that time.
Factors Affecting Bone Health
Several factors can impact your bone health, some that you can control and some that are beyond your control. Among these factors are:
- Ethnicity and heredity. Asian and Caucasian people have an increased risk of osteoporosis, as do those with a parent or sibling who has osteoporosis, or a history of broken bones.
- Women have less bone mass than men, and therefore are more likely to develop osteoporosis. Indeed, according to the International Osteoporosis Foundation, one in three women and one in five men older than 50 years of age will fracture a bone as a result of osteoporosis.
- Age and size. Your bones become thinner and more fragile as you age, and those who are extremely thin (with a body mass index of 19 or less) or are small in build have less bone mass, and are more prone to osteoporosis.
- Weight-bearing exercise helps to build strong bones and slow loss of bone mass. People who are inactive are at an increased risk for fractures and osteoporosis.
- Tobacco use, caffeine intake, and alcohol consumption. Use of tobacco products has been linked to weak bones, and excessive caffeine (4 or more cups per day) or alcohol consumption (more than one or two drinks per day, depending on your gender) can reduce the level of calcium in the body, a nutrient that is critical for bone health. This, in turn, can contribute to bone fragility and fracture.
- Calcium intake. A diet that contains insufficient levels of calcium can lead to reduced bone density, premature bone loss, and an increased risk for fractures.
- Hormonal changes. High thyroid levels and diabetes can cause bone loss, as can low testosterone levels in men. Additionally, in menopausal women and those who do not have regular menstrual periods, the risk of bone loss and osteoporosis is increased as a result of sharply reduced estrogen levels.
- Diseases and disorders. There are many diseases and conditions that can contribute to bone loss. Some of these may include:
- Autoimmune disorders like rheumatoid arthritis and multiple sclerosis
- Gastrointestinal or eating disorders, and related procedures, including celiac disease, Crohn’s disease, and weight-loss surgery
- Blood disorders, like multiple myeloma and leukemia, especially if chemotherapy or steroids are part of the treatment plan
- Medications. Long-term use of steroids, as well as certain anti-cancer and anti-seizure medications, can affect bone health and increase the likelihood of osteoporosis.
Strategies for Promoting Bone Health
Throughout your life, your bones need the right nutrients and care to remain healthy and strong. Indeed, the foundation for bone health begins early in life – even as early as the fetal stage when the optimal nutritional status of the mother can facilitate the normal development of an infant’s skeletal system.
Three key factors will help build and preserve maximum bone mass and avoid the pain, disability, and loss of independence that are associated with bone loss and osteoporosis:
- A balanced diet, with particular attention paid to bone-promoting nutrients
- Weight-bearing exercise
- Healthy lifestyle choices, including avoidance of tobacco and limited alcohol and caffeine consumption
In addition, following these guidelines will assist with maintaining or strengthening your bones:
Adequate calcium intake. Calcium is an essential building block for healthy bones, which store 99 percent of the calcium in your body. The amount required varies at different stages of life, with the highest demand occurring during adolescence. According to the National Institutes of Health (NIH) Office of Dietary Supplements, the recommended dietary allowances (RDA) for calcium at different ages are as follows:
|Table 1: Recommended Dietary Allowances for Calcium|
|0–6 months*||200 mg||200 mg|
|7–12 months*||260 mg||260 mg|
|1–3 years||700 mg||700 mg|
|4–8 years||1,000 mg||1,000 mg|
|9–13 years||1,300 mg||1,300 mg|
|14–18 years||1,300 mg||1,300 mg||1,300 mg||1,300 mg|
|19–50 years||1,000 mg||1,000 mg||1,000 mg||1,000 mg|
|51–70 years||1,000 mg||1,200 mg|
|71+ years||1,200 mg||1,200 mg|
* Adequate Intake (AI)
Calcium-rich foods include dairy products, nuts, leafy vegetables like spinach and kale, broccoli, tofu, and salmon.
Adequate vitamin D intake. Your body needs a sufficient supply of vitamin D to absorb calcium. Sunlight is a natural source of the vitamin, but supplements and dietary sources may be needed if your exposure to sun is limited. Foods that contain high levels of vitamin D include salmon, tuna, canned sardines, egg yolk, and fortified milk. Most experts recommend a daily intake of 600 IU up to 70 years of age, and no more than 4,000 IU per day for adults. Men and women older than 70 should increase their intake to 800 IU.
Protein intake. Protein is a source of essential amino acids, and is crucial for achieving optimal health. It is an especially important component of the diet in children and adolescents, as low protein levels can contribute to decreased bone mass and diminished skeletal growth. In seniors, a lack of protein can result in decreased muscle mass and strength, which can increase the risk of falls. Good sources of protein include dairy products, poultry, lean meat, fish, nuts, lentils, and beans.
Exercise and healthy choices. Exercise and a healthy diet are essential for good health at any age, and these factors are particularly important in boosting bone mass. The avoidance of negative lifestyle patterns, such as smoking and excess alcohol intake, also contributes to optimal bone health, as does maintaining a healthy weight.
Medications. As mentioned earlier, certain medications can have a negative effect on bone health. However, there are also medications that can be effective in reducing the risk of fracture in people with, or at high risk for, osteoporosis. Your doctor can perform a clinical assessment to determine if you are a candidate for such treatment.
Whatever your age, taking steps now to maximize your bone health can increase your chances of enjoying a life of mobility, independence, and pain-free movement.