'Brittle Bones' - The Modern Epidemic
Normal healthy bone has remarkable properties - it is as strong as iron, yet as light as pinewood. Constantly remaking and remodelling itself in response to stress, it replaces almost all its component atoms within a year. It is this characteristic which allows bone to mend even after horrific fractures.
However, when the reabsorption process is faster than the bone production, the bones become soft and brittle, and this condition is referred to as osteoporosis. This can result in fractures, particularly of the hip and wrist; and bone compression and distortion, especially in the spine. Most elderly people show a significant height reduction, and many become stooped as the vertebrae compress.
WHY IS OSTEOPOROSIS SO IMPORTANT?
Apart from the obvious pain and disability associated with the condition, it should be noted that in women over 60 years old, complications following fractures are the most common cause of death. The NHS spends more than £800 million per annum treating over 52,000 fractures, most of which could have been prevented. Osteoporotic bone is easily distorted by weight bearing. When this occurs in the vicinity of a major joint, such as the hip, it is inevitable that osteoarthritis will develop prematurely, especially if the process began relatively early in life.
WHY DOES THIS HAPPEN? There are several factors which make osteoporosis more likely to develop:
Loss of bone density is a normal ageing process, but many young women now show disturbing signs of osteoporosis.
Osteoporosis can develop due to low oestrogen levels, usually due to the menopause in older women. However, young athletes and dancers have low oestrogen levels due to restricted diets and excessive exercise. This makes them a particularly high risk group. The incidence of stress fractures in these groups is increasing continuously.
Bone density is improved by moderate amounts of weight-bearing exercise, such as jogging, walking, tennis etc. However, excessive exercise can have the opposite effect, especially if dietary requirements are not being met - the rate of bone breakdown eventually exceeds the capacity of the bone to repair itself. Enforced bedrest or immobilisation can also lead to osteoporosis.
It is generally acknowledged that a low intake of Calcium can aggravate or cause osteoporosis. Recent research suggests, however, that the dietary influence on bone structure is far more complicated than just the total Calcium intake. Unfortunately, this information is not readily available to the general public, with the result that large sums of money are being spent on Calcium supplements which may have very little long term effect on the strength of the bones.
The main dietary requirements for strong bones are as follows:
f. Vitamin D
g. Vitamin K
There is more Calcium in the body than any other mineral, and 99% is in the bones and teeth. Unfortunately, Calcium is not an easily absorbed mineral - the usual recommended daily intake is given as 700mg - 1500mg in order to allow for the fact that most of the Calcium consumed never actually gets into your body! In the West, most dietary Calcium intake has traditionally come from cheese and milk. However, many people now avoid dairy produce, as this is one of the most common causes of food intolerance. This has created a situation in which Calcium deficiencies are so common as to be almost the norm. Recent surveys in the USA found that the average daily intake was only 50% of that recommended
Sources of Calcium: dairy produce, dark green vegetables, nuts, seeds, beans, lentils, Calcium-fortified cereals, milk and soya.
b. Magnesium has a structural function in bone, and also helps to balance Calcium-controlling hormones. Many authorities believe it to be more important than Calcium in bone health.
Sources of Magnesium: nuts, seafood, whole grains, green vegetables.
c. Boron helps to 'glue' the Calcium to the bone framework.
d. Silica forms very long and strong molecules used in the supporting mechanisms of many tissues, including bone
e. Zinc balances the production of bone-affecting hormones.
f. Vitamin D is essential for the absorption of Calcium and the calcification of bones, especially in children. A deficiency of Vitamin D causes rickets.
g. Vitamin K helps to bind Calcium to bone.
Dietary requirements of bone-building minerals are increased for:
WHAT CAN BE DONE TO PREVENT OSTEOPOROSIS?