Factors that affect bone health

Many factors can affect your bone health and risk of osteoporosis. You can’t control things like your age or family history. But you can control some factors, such as your weight or diet.

Factors include:

  • age – your bones decrease in strength from your thirties
  • gender – osteoporosis is more common in women
  • physical activity – regular exercise helps to keep bones strong
  • diet – it’s important to eat enough protein, calcium and vitamin D
  • family history of osteoporosis – you have a higher risk if your parents have had osteoporosis
  • fractures – breaking a bone after falling from a low height could be a sign of weak bones
  • weight – people with a low body weight are more at risk of fractures
  • smoking – this can reduce bone density, weaken bones and increase the risk of osteoporosis
  • alcohol – drinking more than 21 units of alcohol a week can increase the risk of osteoporosis, as well as the risk of falls
  • illness – some illnesses have been linked to lower bone density
  • medicines – some drugs, such as steroids and anti-epileptic drugs, may increase the risk of fractures and osteoporosis.

Factors that can affect your bone health

Many factors can affect bone health and your risk of osteoporosis. There are some factors you cannot do anything about, such as your age or family history. But there are also factors you can control, such as your diet and levels of physical activity.


Your bones are strongest when you are in your twenties. Bone loss begins in your thirties. The risk of a fracture due to bone loss increases steadily from the age of 50. Fractures are most common in women over the age of 65 and in men over the age of 75.


Both men and women can develop osteoporosis, but it is more common in women. This is because after the menopause, women lose bone density more quickly as their oestrogen levels fall. Oestrogen is a hormone that helps keep bones healthy.

Physical activity

Being physically active when you are a young adult helps make your bones stronger and denser. Regular exercise throughout life helps to maintain your bone strength. Weight-bearing exercises such as walking or climbing stairs are particularly helpful for bone strength.


Family history of osteoporosis

If one, or both, of your parents have had osteoporosis, you are more at risk of developing it too.


If you break a bone after falling from a standing height or less, this is called a fragility fracture. After the age of 50, it can be a sign that you have weaker bones and are more at risk of having a fracture in the future.


People who have a low body weight are more at risk of fractures than people who weigh more.

Body mass index (BMI) is a measure of healthy weight. Your BMI is based on your height and weight. Guidelines recommend that for bone health and general health your BMI should be between 19 to 25kg/m2. Your GP or practice nurse can work out your BMI for you.

We have more information about finding out what your BMI is.


Several studies have shown that smoking reduces bone density, weakens bones and increases the risk of osteoporosis. We have more information about giving up smoking that you might find useful.


Drinking alcohol in moderation is not harmful to bone health. But if you often drink more than 21 units a week, your bone density may be reduced, increasing the risk of osteoporosis.

It is best to keep within the government guidelines of not drinking more than 14 units a week. If you regularly drink as much as 14 units per week, it is best to spread your drinking evenly over three or more days. You should also try to have several alcohol-free days a week. We have more information about alcohol guidelines in our section about looking after your bones.

Drinking alcohol also causes a higher risk of falls, which are a common cause of fractures.


Some illnesses have been linked to lower bone density. These include:

  • diabetes (type 1 and type 2)
  • asthma
  • inflammatory rheumatic diseases, such as rheumatoid arthritis and lupus (SLE)
  • inflammatory bowel diseases, such as Crohn’s disease and ulcerative colitis
  • long-term liver or kidney disease
  • thyroid diseases, such as having an overactive thyroid gland
  • eating disorders, such as anorexia.

If you have a disability that makes walking difficult or makes you less mobile, this can also mean you are likely to have a lower bone density.


Some drugs may increase your risk of fractures and of developing osteoporosis. These include the following:

  • Steroids, which are given to treat a number of illnesses, such as rheumatoid arthritis and asthma. They may also be used in some cancer treatments.
  • Some anti-epileptic drugs, such as phenytoin. Anti-epileptic drugs are mainly used to prevent fits (seizures) in people who have epilepsy.

Back to Bone health

The bones

The bones have several functions in the body, including protecting your internal organs.

Exercise and bone health

Try to find a type of exercise that you enjoy. This means you are more likely to keep doing it.