Are you at risk of osteoporosis? Keep reading for our comprehensive review on some of the most common risk factors.
An estimated 500 million people worldwide have osteoporosis, with osteoporotic fractures occurring approximately every three seconds.¹
Osteoporosis is a ‘silent disease’ that develops without any symptoms until a break occurs. That’s why early awareness of risk is so important.
Understanding your risk for osteoporosis means you can identify if there’s anything you can do to improve your bone health, helping to ensure that fractures don’t occur in the future.
The older you are, the greater your risk of osteoporosis.
Most people will reach their peak bone mass between the ages of 25 and 30.² After this, bones are broken down faster than they are rebuilt, leading to decreased bone density over time.
As we age, our bodies become less efficient at absorbing calcium and other nutrients, further contributing to bone loss.³
Bone mass declines slowly from around age 30 until the menopause, when bone loss accelerates.
In the lead up to menopause, in a stage called perimenopause, the ovaries stop producing as much oestrogen. Oestrogen is an important regulator in bone formation and turnover, and so deficiency can lead to dramatic bone loss. Levels of oestrogen continue to fall throughout the menopause before plateauing at very low concentrations as you reach postmenopause.⁴
About 80% of your peak bone mass is determined by your genes.⁵ Osteoporosis is therefore highly heritable – if you have a close relative who has been diagnosed with osteoporosis, you will be more likely to develop it yourself.⁶
Having low body weight, particularly with a BMI of 21 or less, greatly increases your risk of osteoporosis.
Weight can affect metabolic, immunological, reproductive and musculoskeletal health. Without the right energy stores in body fat, many of the body’s processes are compromised. For example, similarly to during menopause, being underweight can lead to less oestrogen being released from the ovaries. This may contribute to the development of osteoporosis. Low oestrogen can also cause irregular periods and infertility.⁷
Low body weight also often indicates low muscle mass. Muscle mass is closely associated with bone density – with less muscle, less load is put on the skeleton, leading to bone loss.⁸
Previously, high body weight was thought to be protective against osteoporosis. This initial belief was supported by the correlation of high BMI and lower risk of hip fractures in obese adults. But, more up-to-date research has found fracture risk to be dependent on bone location.
Although obese adults are at lower risk of hip fracture, which may be explained by the presence of additional fat tissue acting as padding around the pelvis and femur,⁹ they are at significantly higher risk of fractures in the ankle, leg, arm, spine and ribs.¹⁰
A 2017 study displayed a link between larger waist circumferences and increased pressure on the spine, leading to higher risk of compression fracture.¹¹ Additional body weight also adds pressure on the heels, compromising posture and balance, leading to increased risk of falls.¹²
Obesity is considered a low-grade inflammatory disease; low-grade inflammation is a chronic response to disease that produces a slow, steady level of inflammation throughout the body which can lead to a number of other disorders.
In obesity, immune cells from fat tissue secrete pro-inflammatory cytokines. These are molecules that mediate the inflammatory response. This is harmful to bone, since pro-inflammatory cytokines activate osteoclasts, leading to resorption.
Another way obesity leads to bone loss is related to the increase of fat tissue in bone marrow. Both fat cells and bone cells originate from the same cells in bone marrow, known as mesenchymal stem cells. In obesity, stem cells are more likely to differentiate into fat cells, rather than bone cells, causing further bone loss.¹³
Another common consequence of cytokine release from fat tissue is impairment of insulin, which promotes insulin-resistance.¹⁴ This explains the common co-occurrence of obesity and diabetes.¹⁵
White men and women are at highest risk of fracture compared with other ethnic groups.¹⁶ Rate of fracture is about 50% lower in people from black ethnic groups, and 25% lower for Asian ethnic groups, when compared to white people.¹⁷
Calcium and vitamin D work in tandem to keep your bones healthy. Calcium is needed to maintain bone strength and structure, while vitamin D helps to absorb and regulate levels of calcium. Hence why calcium and vitamin D supplements are so commonly used in the management of osteoporosis.¹⁸
Although the body stores 99% of its calcium in the bones and teeth, it is also found in blood plasma, where it determines calcium balance throughout the entire body. If calcium levels decrease here, calcium resorption from bones is required to restore them.¹⁹ Sufficient dietary intake of calcium is therefore necessary to maintain this balance and stop excessive bone loss.
Proteins are also crucial. They are the building blocks of life, needed to effectively repair bones and muscles.
Ensuring you eat a balanced diet with all three of these important nutrients is key to building stronger bones. Even a well-balanced plant-based diet can provide the body with all the protein, calcium and vitamin D it needs.
Certain lifestyle habits can easily play havoc with your bone health. Smoking and vaping in particular have a clear cut damaging effect, often messing with hormonal regulation to bring forward the onset of menopause by a few years.
Discover more on the effects of smoking, as well as caffeine and alcohol, in our blog, Are my lifestyle choices affecting my bone health?.
Diabetes and hyperthyroidism are common endocrine disorders. These are disorders that are the result of a dysfunction of the endocrine system – this is the system responsible for the releasing hormones throughout the body.
Diabetes is a chronic disease that occurs either as a result of the pancreas not producing enough insulin, or the body not being able to effectively use the insulin it produces. Without normal regulation by insulin, a person’s blood sugar level becomes too high.
High blood sugar is known to inhibit osteoblast function to prevent bone formation, and increase osteoclast function to accelerate bone loss.²⁰
Type I diabetes is usually diagnosed in young children, prior to the time at which peak bone mass is reached, whereas type II is more commonly diagnosed in adults, after peak bone mass has been attained. Consequently, bone density is often lower in type I than in type II diabetes.²¹
For more information on the association between diabetes and bone health, check out our blog, Diabetes and osteoporosis: is there a link?.
An overactive thyroid, also known as hyperthyroidism, is where the thyroid gland produces too much of the thyroid hormones.
Thyroid hormones are essential for normal development of the skeleton in adolescents and normal bone metabolism in adults, but having too much circulating in the blood can have detrimental effects.
Hyperthyroidism increases activity of osteoclasts and suppresses activity of osteoblasts. This imbalance of bone formation and resorption results in net loss of bone density. Some studies support the idea that hyperthyroidism reduces bone density by up to 10% every bone remodelling cycle.²²
Crohn’s disease is a condition that causes inflammation in the digestive system. As many as 60% of people with the disease have below average bone density.²³
As vitamin D and calcium are absorbed in the small intestine, people with Crohn’s – particularly those who have had their small intestine removed or who have extensive small intestine inflammation – are likely to be both calcium and vitamin D deficient.
Coeliac dsease is an autoimmune condition which causes gluten intolerance and, similarly to Crohn’s, disrupts the absorption of nutrients in the small intestine. People who are coeliac also experience calcium and vitamin D deficiency.²⁴
Furthermore, the autoimmune response associated with coeliac disease promotes the growth of osteoclasts via the release of pro-inflammatory cytokines.²⁵ Poor absorption of calcium and vitamin D, combined with activation of osteoclasts by pro-inflammatory cytokines, increases bone resorption, which is revealed by low T-scores on DEXA scans. However, changes in bone density in coeliac disease have been shown to be reversed with early intervention of a gluten-free diet.²⁶
Rheumatoid arthritis is an autoimmune condition that causes joint inflammation. This inflammation leads to the release of cytokines, which activate osteoclasts, leading to the breakdown of bone.²⁷ This makes people with rheumatoid arthritis highly susceptible to osteoporosis.
Studies have also shown that postmenopausal women with recent a onset of rheumatoid arthritis have impaired calcium absorption.²⁸
Likelihood of osteoporosis is 3.7 times higher in people with HIV when compared to those without, and prevalence of low bone density can be up to 87.5%.²⁹
Hypogonadism, which describes low functional activity of the gonads (testes and ovaries), commonly affects HIV-positive men, resulting in low testosterone.³⁰ Testosterone usually acts directly on osteoblasts to promote bone formation; without it, bones weaken.³¹
In a 2008 study, over 5% of HIV positive women reached menopause prematurely, suggesting that HIV also impacts the ovaries. HIV-positive women also experience decreased fertility.³² With dysfunctional ovaries, not enough oestrogen is released to regulate healthy bone metabolism.
Hypogonadism is also common in periods of chronic stress.
People with HIV also have an increased risk of vitamin D deficiency.³³ HIV causes an increase in pro-inflammatory cytokines, which stop the body from synthesising vitamin D.³⁴
In addition, some HIV medications can weaken bones, especially in the first year of treatment, but this can be partially alleviated if taken alongside calcium and vitamin D supplements.³⁵
Patients with anorexia increase their risk of osteoporosis by up to 40%.³⁶ To learn more about the ways eating disorders can affect your bones, read our blog, Anorexia and osteoporosis – what’s the link?.
Steroid medications, including glucocorticoids, can affect your bone health in a number of ways. This effect is more apparent when taken as oral tablets, in high doses, or for periods longer than three months.
Steroid treatments have many uses. They can help to reduce inflammation in conditions such as asthma, rheumatoid arthritis and inflammatory bowel disease, and boost hormone levels in adrenal and pituitary disorders. They can also lower the risk of your body rejecting a new organ after a transplant.
Steroids have a significant effect on how the body uses calcium and vitamin D. Glucocorticoids inhibit calcium absorption, partly by decreasing the action of vitamin D. They also increase the amount of calcium lost in urine.³⁷ This means there is less calcium available for your bones.
Glucocorticoids also slow down the activity of osteoblasts, while speeding up the activity of osteoclasts. They can negatively affect the secretion of oestrogen and testosterone, too.³⁸ All of these factors contribute to suppression of bone formation and promotion of bone loss, which can lead to osteoporosis.
Medicines used to treat breast cancer and prostate cancer that affect hormone levels can increase your risk of osteoporosis. Chemotherapy and radiotherapy prevent ovaries from working by blocking oestrogen release and inducing early menopause. Similarly, hormone therapy used alongside chemotherapy and radiotherapy for prostate cancer can lower or block testosterone in the body.³⁹
These hormones play a critical role in bone health. Read all about them in our blog: How Do Your Hormones Affect Osteoporosis?.
If you think that you could be at risk of osteoporosis, speak to your GP or another relevant healthcare professional. They will often use your risk factors to build up a picture of your overall bone health, to assess your likelihood of breaking a bone.
The Royal Osteoporosis Society has an osteoporosis risk checker on their website, which can give you an idea of your own risk in just five minutes. Check your osteoporosis risk.
If you are at high risk, your doctor will be able to refer you for a DEXA scan to measure your bone density; this will be able to determine the best route to take to protect your bone health.