Our bones lose density and strength as we age, but that doesn’t have to mean they’ll break. Follow our expert advice for keeping your skeleton in good shape.
Healthy bones are key to staying active in later life. Our skeletons are made up of more than 200 bones, which support our weight, enable us to move and protect our internal organs. Once we hit middle age, bone density starts to decrease. This raises the risk of osteoporosis, the bone-thinning disease that affects more than three million people in the UK. It tends to be symptom-free and painless – until you break a bone. ‘Osteoporosis is a major factor in the one in two women, and one in five men, who will break a bone after the age of 50,’ says Nicholas Harvey, Professor of Rheumatology and Clinical Epidemiology at the Medical Research Council’s Lifecourse Epidemiology Unit at the University of Southampton. ‘Although it’s not easy to increase bone density in later life, the right diet and exercise can make a significant difference.’
The bare bones
Bones are made up of a thicker outer shell called cortical bone and an inner honeycomb of tiny struts called trabecular bone. Old bone is removed by cells called osteoclasts and replaced by bone-building cells called osteoblasts in a continual cycle. Osteoporosis occurs when this cycle is imbalanced and the struts become thin. ‘It’s like a dodgy builder leaving out essential bits of scaffolding,’ says Professor Harvey. ‘The cortical bone develops tiny holes and the bone becomes less dense and more liable to break. ‘However, in recent decades, we’ve moved away from the perception of osteoporosis as an inevitable consequence of ageing to that of a treatable chronic disease,’ adds Professor Harvey.
Genes: These are thought to affect bone health. While we can’t change our genetic make-up, lifestyle factors make a big difference.
Gender: Women have smaller bones than men, and lose the bone-protective role of oestrogen after the menopause.
Low calcium and vitamin D: Calcium is vital for strong bones, while vitamin D is important for its absorption.
Alcohol and smoking: Both are toxic to bones as they impair bone cell function.
Weight: A healthy BMI is important. Being obese or underweight both affect bone health.
Steroids: Long-term use can affect bone formation.
Overactive parathyroid gland: This affects the amount of calcium in the blood.
Type 2 diabetes: ‘Although the link is not yet well understood, this does impact on bone strength,’ says Professor Harvey.
A DEXA scan of the bone density of the hips and spine, and sometimes wrist, is usually the first step. The results are given as T-scores. A T-score of -2.5 used to diagnose osteoporosis. ‘However, we’ve moved on from just looking at bone density,’ says Professor Harvey. ‘We now recommend a system called FRAX, which works out the absolute probability of a fracture in the next 10 years, based on a range of factors. Age is also important. Even with a low T-score of -2.5, if you’re 55, your risk of a fracture is considerably lower than that of an 80-year-old.’
The most common medicines are bisphosphonates, which slow down the activity of the osteoclasts, allowing the bone-building osteoblasts to do their work. Alendronic acid is the most commonly prescribed generic drug, and is given weekly.
A relatively new kid on the block, says Professor Harvey, is the denosumab injection, given twice a year. Raloxifene, a drug related to oestrogen (only used in women), reduces the risk of spinal fracture. For patients with severe osteoporosis, parathyroid hormone treatment is the only one that actually builds bone. ‘As all medicines have side effects, we now re-evaluate the risk of fracture after three to five years,’ says Professor Harvey. ‘If the risk of fracture has declined, a period off treatment for a year or so may be appropriate.’ Calcium and vitamin D supplements are often given alongside medicines to improve bone health. The current health guidelines advise daily vitamin D supplements (400iu) for those 65 and over, as well as for those who don’t spend time in the sun or cover up for cultural reasons.
For more on osteoporosis and a bone-friendly lifestyle, visit nos.org.uk or call the free helpline on 0808 800 0035.
Muscles are important too. Along with bone density, we also lose muscle mass as we age, at a rate of half to one per cent a year from around the age of 40. This is known as sarcopenia. However, research shows the right exercise and a healthy, balanced diet can improve muscle mass and strength, and may even reverse its decline. Use free/fixed weights or stretchy resistance bands, and slowly build up to heavier weights or stronger bands. Check with your GP or a physiotherapist for a routine that’s suitable for you. Yoga, t’ai chi and Pilates also improve muscle mass.
Caution: If you already have osteoporosis, particularly in the spine, avoid weightlifting and the rowing machine.
9 easy ways to protect your bones
- Boost your calcium: Adults need around 1g calcium a day. Good sources include dairy products, almonds and Brazil nuts, green leafy veg (which also supplies bone-friendly vitamin K) and wholemeal bread. ‘If you don’t get enough from your diet, consider taking a supplement,’ says Professor Harvey. Check your intake at iofbonehealth.org/calcium-calculator.
- Get some sunshine: Vitamin D is vital for the absorption of calcium. Boost your levels by exposing your skin to the sun, without sunscreen, for 10-15 minutes a day from April to October. It’s hard to get enough vitamin D from diet, but the best source is oily fish (‘Wild, not farmed,’ says Professor Harvey). As the sun isn’t strong enough in the UK in winter, consider taking a daily 400iu supplement.
- Avoid fizzy drinks: The phosphoric acid in fizzy drinks may increase the loss of calcium from bones.
- Don’t forget protein: Some experts believe we need more protein as we get older. Eat at least 1-1.2g protein per 1kg of body weight per day. Make sure it’s good quality, lean protein, such as chicken, turkey, fish or eggs.
- Don’t smoke: Tobacco has a toxic effect on bones and can also lead to earlier menopause and the loss of bone-protective oestrogen.
- Eat at least five a day: Fruit and particularly veg are a rich source of nutrients, and help to reduce calcium loss.
- Cut down on alcohol: This has a toxic effect on bones, and blocks the absorption of calcium and vitamin D. The Chief Medical Officer recommends a maximum of 14 units a week for men and women, consumed over at least two or three days, with a couple of alcohol-free days a week.
- Keep salt to less than 6g a day: A high intake increases calcium loss.
- Take regular weight-bearing exercise: Try brisk walking, dancing, tennis – encouraging the muscles to ‘pull’ on the bones helps to make them stronger. Balance is also important to prevent falls, so try t’ai chi or yoga.
Check your risk of osteoporosis at nos.org.uk/risk or talk to your GP.
Brisk walking and exposing your skin to the sun every day helps to build strong, healthy bones