Osteoporosis literally means ‘bones with holes’. It occurs when bones lose minerals such as calcium more quickly than the body can replace them. Bones become less dense, lose strength and break more easily.
Most people don’t realize they have osteoporosis until a fracture happens, as there are usually no signs or symptoms. This is why osteoporosis is often called the ‘silent disease’.
Osteoporosis and bone growth
Bone is formed by specialized cells. It is constantly being broken down and renewed. It is living tissue that needs exercise to gain strength, similar to muscle.
In the early years of life, more bone is made than is broken down, resulting in bone growth. By the end of your teens, bone growth has been completed and by about 25 to 30 years of age, peak bone mass is achieved.
Sex hormones, such as oestrogen and testosterone, have a fundamental role in maintaining bone strength. The fall in oestrogen that occurs during menopause results in accelerated bone loss. During the first five years after menopause, the average woman loses up to 10 per cent of total bone mass.
Fractures of the spine caused by osteoporosis can lead to pain, loss of height and changes in posture, such as the ‘dowager’s hump’. This hump is caused when spinal fractures are compressed due to the force of gravity, resulting in an abnormal bending forward of the spine called kyphosis.
Symptoms & diagnosis of osteoporosis
Osteoporosis causes no specific pain or symptoms. However, it does increase the risk of serious or debilitating fractures. If you think you may be at risk of developing osteoporosis, see your doctor.
The most reliable way to diagnose osteoporosis is with a bone density scan which is usually done at the hip. Talk to your doctor about having this done.
Risk factors for osteoporosis
- inadequate amounts of dietary calcium and vitamin D
- cigarette smoking
- alcohol intake of more than two standard drinks per day
- caffeine intake of more than three cups of coffee or equivalent per day
- lack of physical activity
- early menopause (before the age of 45)
- long-term use of medication such as corticosteroids for rheumatoid arthritis, asthma and other conditions.
Prevention of osteoporosis
From a young age you can take steps to prevent osteoporosis:
- have a healthy and varied diet with plenty of fresh fruit, vegetables, whole grains, and calcium rich foods
- absorb enough vitamin D
- avoid smoking
- do regular weight-bearing and strength-training activities.
Calcium-rich diet and osteoporosis
Enjoying a healthy, balanced diet with a variety of foods and an adequate intake of calcium is a vital step to building and maintaining strong, healthy bones. If there is not enough calcium in the blood, your body will take calcium from your bones. Making sure you have enough calcium in your diet is an important way to preserve your bone density.
It is recommended that the average Australian adult consumes 1,000 mg of calcium per day. Postmenopausal women and men aged over 70 years are recommended to have 1,300 mg of calcium per day. Children, depending on their age, will need up to 1,300 mg of calcium per day.
Dairy foods have the highest levels of calcium, but there are many other sources of calcium, including sardines, spinach and almonds. If you are unable to get enough calcium from your diet alone, you may need to talk to a health professional about calcium supplements.
Vitamin D and osteoporosis
Vitamin D and calcium promote bone density. Vitamin D is important because it helps your body absorb the calcium in your diet. We obtain most of our vitamin D from the sun, and there are recommendations for the amount of safe sun exposure for sufficient vitamin D production, depending on your skin type, geographical location in Australia and the season.
Vitamin D can also be found in small quantities in foods such as:
- fatty fish (salmon, herring, mackerel)
- fortified foods such as low-fat milks and margarine.
For most people, it is unlikely that adequate quantities of vitamin D will be obtained through diet alone. Talk with your health professional about vitamin D supplements if you are concerned that you are not getting enough vitamin D.
Exercise to prevent osteoporosis
Weight-bearing exercise encourages bone density and improves balance so falls are reduced. It does not treat established osteoporosis. Consult your doctor before starting a new exercise program, especially if you have been sedentary, are over 75 years of age or have a medical condition.
General recommendations include:
- Choose weight-bearing activities such as brisk walking, jogging, tennis, netball or dance. While non-weight-bearing exercises, such as swimming and cycling, are excellent for other health benefits, they do not promote bone growth.
- Include some high-impact exercise into your routine, such as jumping and rope skipping. Consult your health professional – high-impact exercise may not be suitable if you have joint problems, another medical condition or are unfit.
- Strength training (or resistance training) is also an important exercise for bone health. It involves resistance being applied to a muscle to develop and maintain muscular strength, muscular endurance and muscle mass. Importantly for osteoporosis prevention and management, strength training can maintain, or even improve, bone mineral density. Be guided by a health or fitness professional (such as an exercise physiologist) who can recommend specific exercises and techniques.
- Activities that promote muscle strength, balance and coordination – such as tai chi, Pilates and gentle yoga – are also important, as they can help to prevent falls by improving your balance, muscle strength and posture.
- A mixture of weight-bearing and strength-training sessions throughout the week is ideal. Aim for 30 to 40 minutes, four to six times a week. Exercise for bone growth needs to be regular and have variety.
Lifestyle changes to protect against osteoporosis
Be guided by your doctor, but general recommendations for lifestyle changes may include:
- stop smoking – smokers have lower bone density than non-smokers
- get some sun – exposure of some skin to the sun needs to occur on most days of the week to allow enough vitamin D production (but keep in mind the recommendations for sun exposure and skin cancer prevention)
- drink alcohol in moderation, if at all – excessive alcohol consumption increases the risk of osteoporosis. Drink no more than two standard drinks per day and have at least two alcohol-free days per week
- limit caffeinated drinks – excessive caffeine can affect the amount of calcium that our body absorbs. Drink no more than two to three cups per day of cola, tea or coffee.
**Source: Better Health Channel