Does cancer affect my bone health?

Our bones are continuously being broken down and rebuilt again. As we age, the ability to rebuild our bones naturally decreases so bones tend to get thinner. This is known as reduced bone density.

Some illnesses and treatments can make this worse.

The decrease in bone density is also called osteoporosis. Lower bone density increases the risk of bone fractures.

Bone thinning is common in postmenopausal women and in men aged 70 and over.

Bone thinning after cancer diagnosis

The risk of bone loss increases in cancer patients. This can be due to the disease itself, or by cancer treatments such as some forms of chemotherapy, radiotherapy, hormone therapy, or removal of the ovaries or testes.

Early menopause can also cause bone thinning in women. Early menopause can be caused by low levels of oestrogen in the blood after cancer treatment.

The risk of osteoporosis also increases in men who have prostate cancer. People who are at risk of osteoporosis and bone thinning may be given bisphosphonates by their doctor. Bisphosphonates are drugs that help prevent or slow down bone thinning.

A combination of adequate dietary calcium, vitamin D levels and exercise may help to reduce bone thinning.

Calcium in your diet

Dairy products such as cheese, milk and yoghurt provide a good source of calcium. Green leafy vegetables, nuts, beans and pulses also provide calcium. Sometimes calcium is added to plant products, such as soy drinks, but check the label to see if has had extra calcium added. A dietitian can advise you on how to get enough calcium in your diet.

> Take a look at our recipes for cancer patients

How much calcium and vitamin D do I need?

It’s recommended that adults aged 19-64 years need 700 mg of calcium daily. If you are taking osteoporosis medication this increases to 1000mg/day with at least 10 micrograms of vitamin D a day.

If you do not get enough calcium from food, you could take a calcium supplement. This is often combined with a vitamin D supplement. Always talk to your doctor or a dietitian before taking any supplements.

Taking too much calcium or vitamin D is not good for your health. Don’t take a supplement with more than 100% of the Reference Nutrient Intake (RNI) – the RNI tells you how much of a vitamin or mineral you need in a day.

What is Vitamin D?

Vitamin D is a fat-soluble vitamin and is one of the few vitamins that our body can make itself – it’s formed when our skin is exposed to sunlight. We also get vitamin D from food such as oily fish, eggs, liver, and fortified spreads and cereals.

Vitamin D is necessary for the absorption of calcium from our diet – this is important for the growth and maintenance of healthy bones and teeth. Without vitamin D, calcium absorption can decline.

Certain groups of people are more at risk of vitamin D deficiency. Risk factors for being deficient in vitamin D include being older, being housebound or spending a lot of time inside, those who wear clothes that cover most of their skin and those with dark skin from African, Afro-Caribbean or South Asian backgrounds.

In the UK the sun should be strong enough between April and the end of September for your body to produce enough Vitamin D. You should continue to follow guidance on staying safe in the sun.

Keeping active and exercise

Getting enough calcium and vitamin D is not enough to prevent bone loss. It’s also important to do weight-bearing exercises to help keep your bones strong – this includes doing muscle-strengthening activities (such as squats), walking, climbing stairs, and dancing.

It’s also important to watch how much salt, alcohol, or caffeine you eat or drink every day. Caffeine is found in tea, coffee and some fizzy drinks. Excessive caffeine can make you lose extra calcium in the urine. Decaffeinated (where the caffeine has been removed) tea and coffee are readily available.

Our advice

Make sure you eat enough calcium and vitamin D in your diet.

Keeping active outside (during the summer) can help prevent bone loss. Being exposed to the sun’s rays can help increase your vitamin D levels. Just be careful to not overexpose your skin to the sun, especially on a hot day, which can help to keep your bones healthy.

Note: while there may be certain situations where a vitamin D supplement is required all year round, speak to your doctor or dietitian first before taking any supplements.

> Read our recommendations on Sun, UV rays and cancer risk

> Should I take dietary supplements during cancer treatment?

> Should I take Vitamin D if I have or have had breast cancer?

> Should I take Vitamin D if I have or have had prostate cancer?


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