Preventive measures aim to ensure maximum accumulation of bone tissue during skeletal growth and maturation, as well as reducing bone loss after the skeleton matures.
The approaches therefore differ during each life stage. Adolescence and young adulthood are the times to build skeletal reserve, while midlife provides the opportunity to preserve bone mass and assure bone health in future years. In later life, those who may already have developed osteoporosis can take measures to prevent further bone loss and fractures.
Certain risk factors that predispose to the developing of osteoporosis can’t be altered: you can’t change your gender, race or age. However, you can do much to prevent further bone loss.
A balanced diet that contains adequate kilojoules, vitamins and minerals is required to maintain bone health. Sufficient kilojoules, protein and vitamin C will ensure normal collagen synthesis.
Calcium is probably the most important bone-building mineral. It’s a well-known fact that the diet of most individuals in western countries contain insufficient calcium to maintain a positive calcium balance.
Reasons for limited consumption include a distaste for dairy products, fear of kilojoules and fats (although skim milk actually contains slightly more calcium than full cream milk), true milk allergy (this is rare in adults) and lactose intolerance, which occurs frequently in the elderly, as well as the black and Asian populations. Fermented lactose products like cheese and yoghurt are, however, tolerated by most.
Whereas calcium is an essential mineral required to build bone mass and slow age-related bone loss, calcium alone won’t protect against bone loss resulting from oestrogen deficiency in post-menopausal women. It also won’t provide protection against the bone loss caused by physical inactivity, smoking, alcohol abuse or the use of bone-toxic drugs. Sufficient calcium is just one of the many steps you need to take to ensure a healthy skeleton.
Debunking milk and dairy myths
When it comes to this important food group, myths abound. Brush up on the facts:
The benefits of dairy include the following:
- Dairy is an excellent source of calcium, phosphorus, protein and other nutrients that are important for both bone and overall health.
- Calcium is vital for strong bones and is a major building block of the skeleton – 99% of the kilogram of calcium in our bodies are found in our bones and teeth.
- Milk and other dairy products are the cheapest and most readily available sources of calcium.
- Scientific evidence strongly supports the benefits of dairy products for bone and muscle health – bone loss is reduced and muscle mass improved with adequate dairy intake.
- In some countries, including South Africa, certain milks are fortified with vitamin D – an added benefit to bone health.
Dairy vs other calcium sources:
- Dairy foods are rich sources of calcium with the added advantage of providing protein and potassium.
- Non-dairy foods containing calcium include green vegetables like kale and broccoli, whole canned fish with soft edible bones such as sardines, some nuts (e.g. almonds), and calcium-set soy products (tofu, soy milk).
- You’d have to eat numerous servings of these non-dairy foods to get the equivalent amount of calcium provided by just one serving of yoghurt, cheese or milk.
- For children who often avoid green vegetables, dairy products are often the preferred source of calcium (it provides up to 80% of dietary calcium intake) and protein. Both nutrients are essential for growing bones.
A few other myths and facts
MYTH: Milk and other dairy foods aren’t good for bone health because they’re “acid-forming”. As a result, calcium is leached from the bones to prevent the body from becoming too acidic.
FACT: Milk and yoghurt are not “acid-forming” foods. They produce a neutral residue when digested. In contrast, hard cheeses such as parmesan and cheddar are acid-forming. The acid produced from consuming hard cheeses can be neutralised by the ingestion of more fruits and vegetables.
As long as you’re getting a reasonable amount of calcium from your diet, your body will ensure that you have the right amounts of calcium circulating in your body. If your calcium intake is too low to maintain adequate calcium blood levels, calcium will be released from your bones. This can weaken them.
MYTH: Western countries, where people tend to consume more dairy foods compared to other cultures, are more prone to osteoporosis and broken bones.
FACT: Many factors determine whether a person will develop osteoporosis and be at increased fracture risk (see our article on “risk factors”). Dairy foods aren’t responsible for higher fracture rates, nor does dairy consumption alone guarantee strong, healthy bones.
MYTH: People with lactose intolerance or sensitivity can’t consume any dairy products.
FACT: Very few people in western countries are completely lactose intolerant, although a large number of the South Africa black population may be lactose sensitive.
Most lactose-intolerant people can, however, enjoy the fermented dairy products like cheese and yoghurt, and even small quantities of milk. Some people may also take lactase tablets, if required.
Vitamin D plays two major roles in the development and maintenance of healthy bones. It aids in calcium absorption from the intestine and also ensures correct renewal and mineralisation of bone. It’s also essential for muscle health.
Vitamin D is made in the body when the skin is exposed to UV-B rays in sunlight. Due to increasing time spent indoors and other factors such as pollution, the use of sunscreen, skin pigmentation and advanced age, low levels of vitamin D have become a global problem jeopardising bone and muscle health in populations everywhere.
Generally speaking, you should try to get 10-20 minutes of sun exposure to your bare skin (face, hands and arms) outside peak sunlight hours (before 10am and after 2pm) daily, without sunblock. Darker skins need longer exposure time – 20-30 minutes a day. We all need about 600 International Units (IU) of vitamin D per day.
Those at higher risk for vitamin D deficiency (older adults, obese people, people who get no sun exposure, people with absorption diseases like Chrohn’s disease), need to be supplemented after consultation with their doctor. Seniors 60 years and older need to be supplemented with approximately 800IU/day vitamin D. Supplementation at these levels has been shown to reduce the risk of falls and fracture by about 20%.
Up your vitamin D intake with the following foods:
Vitamin D content
Shiitake mushrooms, fresh
Shiitake mushrooms, sun-dried
20 IU per yolk
*per 100g unless otherwise stated
IU: International Units
Protein provides the body with a source of essential amino acids necessary for health. A low protein intake during childhood and adolescence can affect skeletal growth and also affect skeletal and muscle health in the aged. This leads to an increased risk of falling.
Many people have been scared by claims that a high protein intake (including drinking milk) can lead to an increased calcium loss via the kidneys and is therefore bad for bones. This claim has been disproved by many studies.
The current recommended daily allowance for healthy adults is 0.8g of protein per kilogram of body weight per day. Protein-rich foods include dairy products, eggs, meat, fish, lentils, beans and nuts.
Micronutrients that support bone health
Vitamin K: Found in leafy green vegetables like spinach, broccoli, kale and cabbage. It’s also found in liver, some fermented cheeses and dried fruit (especially prunes).
Magnesium: Found in green vegetables, legumes, nuts, seeds, unrefined grains, fish and dried fruit. Fifty grams of almonds yield about 40% of your daily need.
Zinc: Found in lean red meat, poultry, whole-grain cereals, pulse legumes and dried fruit. Beans and chickpeas are good sources.
Carotenoids: These precursors to vitamin A are found in many vegetables, including leafy green vegetables, carrots and red peppers. Just 50g of raw carrots meet your daily needs.
Calcium: Supplements should be considered if your dietary intake is insufficient.
Calcium isn’t found free in nature and is usually bound to a salt (e.g. calcium carbonate, calcium citrate, calcium lactate). Since these salts all yield different amounts of elemental calcium (the calcium that gets absorbed), it’s important to know what the elemental calcium content of your supplement is to know how much of it you should take per day.
The National Osteoporosis Foundation of South Africa (NOFSA) recommends a total daily intake (diet and/or supplements) of approximately 1000mg per day. One supplement of approximately 500-600mg per day should be sufficient if you have a diet that’s deficient in calcium.
Remember to take calcium carbonate supplements with a low-fibre meal (e.g. supper) as it needs stomach acid to be absorbed.
Also keep the following in mind when taking calcium supplementation:
- If you need to take an iron supplement as well, take your calcium supplement either two hours before or after the iron supplement to ensure proper absorption of both.
- Calcium may interfere with your body's ability to use certain antibiotics like tetracycline. Take your calcium two hours before or after taking the tetracycline.
- If you’re using a bisphosphonate drug for osteoporosis, don’t take the calcium supplement in the morning as it will interfere with the absorption of the medication.
- Calcium absorption is inhibited to a certain degree by fibre in the diet. Try taking your calcium when you’re having a low-fibre meal.
- Special care should be taken when considering supplements that contain oyster shells, dolomite or bone meal as these may contain high doses of lead. This can be harmful in the long run.
Regular exercise is important at all ages as it’s the only physiological way to stimulate bone formation. People who exercise regularly tend to have higher peak bone mass.
Exercise also seems to slow down age-related bone loss.
The exact mechanism of how exercise influences bone turnover isn’t known, but we do know the following:
- The muscle pull on bone generates piezoelectrical charges on bone surfaces. This stimulates osteoblast activity and bone formation.
- Exercise causes the release of hormones that promotes bone formation.
- Exercise stimulates blood flow within the bone.
- Exercise improves balance, co-ordination and confidence, thereby helping to prevent falls. It also strengthens muscles and flexibility, and protects against fractures in the event of a fall.
- Weight-bearing exercise like brisk walking, stair climbing, jogging and dancing is better than non-weight bearing exercise like swimming or cycling. It is, however, excellent to start with these exercise if you haven’t exercised in a while.
- A brisk 45-minute walk at least 3 times per week is recommended. Wear comfortable shoes with good arch and heel support.
- Exercises that help to improve your posture and strengthen the pelvic floor, back and stomach muscles are also very important (e.g. Pilates, yoga).
Exercise plays an important role in building and maintaining bone strength. Just like muscles, bones respond when they’re stressed. In other words, when they are forced to bear more weight than they’re used to. This can be achieved by weight-bearing or impact exercises.
The International Osteoporosis Foundation (IOF) offers excellent information on specific exercise programmes that have been shown in scientific studies to improve or maintain bone health in men, women and children at various life stages.
Note that many of the regimens and images on the IOF website aren’t appropriate for everyone, and should only be carried out under professional supervision.
3. Smoking, alcohol and bone-toxic drugs
Tobacco and alcohol’s detrimental effect on bone tissue have already been discussed. If you’re serious about your health, and want to prevent osteoporosis, it’s important not to abuse these bone-toxic substances.
If you need to take other drugs that are detrimental to bone health, e.g. cortisone, ARVs, anti-epileptic drugs, cancer medications (as discussed under risk factors), be extra vigilant with your diet and exercise regimen and have a regular bone-mineral density test done to monitor your bone health.
Adopting a bone-healthy lifestyle (whether you have osteoporosis or not) is of critical importance throughout life. This needs to start during childhood and adolescence, and be maintained as you age.
Controlling your osteoporosis risk factors, and complying with treatment regimens if prescribed, will help you to live a mobile, independent, fracture-free life for longer.
Reviewed by Teréza Hough, CEO of the National Osteoporosis Foundation of South Africa: www.osteoporosis.org.za. October 2017.