Dietary advice tips
(9) Osteoporosis
Osteoporosis is a condition characterised by progressive loss of bone tissue, which leads to fragile bones and increased risk of fracture, particularly of the hip, wrist and vertebrae. Some degree of osteoporosis is inevitable with ageing, but a number of risk factors influence both the achievement of peak bone mass (which normally occurs by the age of 30 years) and loss of bone in middle and later life. Women are at greater risk than men because they have smaller, less dense bones than men and because of the loss of oestrogen that occurs after the menopause. Other risk factors include a lower than ideal body weight (particularly a reduced amount of body fat), poor calcium intake, being Caucasian or Asian rather than Afro-Caribbean, excessive alcohol intake, smoking, inactivity and early menopause. Individuals who have a prolonged history of dieting or anorexia nervosa or who have had prolonged steroid treatment are also at risk.
- Dietary factors most likely to encourage excessive bone loss include poor calcium intake (eg, low consumption of milk and dairy products), lack of vitamin D (due to minimal exposure to sunlight or low intake of foods containing vitamin D) or an unhealthy diet overall (eg, excessive coffee, excessive alcohol, smoking, high sugar and high fat snacks).
- The most important time to reduce the risk of osteoporosis is early in life, throughout childhood and adolescence. Bone mass declines after the age of 30 years and, once calcium has been lost from the bone, it cannot be replaced with dietary or supplemental calcium. However, encouraging calcium intake may help to reduce further bone loss.
- The overall diet should be based on healthy eating guidelines (ie, plenty of fruit and vegetables, bread, cereals, lean meat or fish, legumes and dairy products). Although emphasis is often given to calcium, other nutrients such as magnesium, potassium and antioxidants may help to maintain bone health.
- Milk and dairy products are the richest and most bioavailable dietary sources of calcium. Encourage two to three servings a day of foods such as milk, yoghurt, cheese or fromage frais. Low fat or reduced fat varieties contain just as much calcium as full fat products.
- Discourage excessive consumption of coffee, alcohol and salt. All these substances in excess may contribute to calcium loss.
- Emphasise the importance of vitamin D. Encourage people to go outside as much as possible. Most people will obtain sufficient vitamin D from sunlight exposure. In addition, encourage consumption of foods fortified with vitamin D (eg, margarines, fat spreads and breakfast cereals). Oily fish is also a good source.
- People who are housebound or immobile, vegans, others who consume no dairy produce and the elderly may benefit from a supplement containing the recommended daily amount of calcium and vitamin D.
- Exercise is important. Weight bearing exercise (eg, walking, skipping, running) helps to maintain bone mass, but all types of exercise help to encourage mobility and reduce the risk of falls.
This series of "dietary advice tips" is intended to be a reminder of the main points to be made by pharmacists when giving nutritional information to the public. The conditions included in the series are those where diet is a well recognised risk factor, those in which diet contributes to the management of the condition, and others for which patients may welcome sound dietary advice. The series is written by Dr Pamela Mason (a pharmacist with a postgraduate qualification in nutrition)
