Osteoporosis is the most common bone disease with estimates suggesting that about half of all women and one in four men older than 50 will break a bone because of osteoporosis. In osteoporosis, bones become weak and are more susceptible to breaking. In osteoporosis, there is a decrease in bone mineral density, the architecture of the bone. As this declines the bone deteriorates and there is an increased risk for bone fractures.

Often, breaking a bone is the first clue that you have osteoporosis. However a bone mineral density test can be done to tell if you have osteoporosis before you have symptoms of the disease. This makes it possible to treat and manage osteoporosis early to prevent broken bones.

WHAT ARE THE SIGNS AND SYMPTOMS OF OSTEOPOROSIS?

Bone fractures are the most obvious sign of osteoporosis, making osteoporosis severely disabling. Spinal and vertebral fractures may lead to loss of height, severe back pain, and spinal deformations. Hip fractures may require hospitalisation and major surgery. It can also affect your posture causing your back to become stooped or hunched.

There are several diseases and conditions that may cause bone loss. Sometimes, merely treating the condition that causes bone loss may improve your bone health. These diseases include AIDS/HIV, celiac disease, diabetes, haemophilia, inflammatory bowel disease (Crohn’s disease and ulcerative colitis), liver disease, lupus, multiple sclerosis, Parkinson’s disease, rheumatoid arthritis, overactive thyroid, gastric bypass, and any malabsorption syndrome. Conditions such as eating disorders, depression and organ transplants may also affect bone health. If you have these health problems it is important to take immediate action to keep your bones healthy.

FACTORS THAT PUT YOU AT RISK FOR OSTEOPOROSIS

Being at risk for osteoporosis means you are more likely to get this disease. While you have no control over some risk factors there are others you can change.

Risk factors that cannot be changed

Unfortunately, there are some non-modifiable risk factors that may put a person at an increased risk for developing osteoporosis. These include: 

Advanced age  Though osteoporosis can affect anyone at any age, it is far more common in the elderly. As age increases, so does the risk for developing osteoporosis (though it doesn’t mean that all old people will get osteoporosis).
Menopause      The hormone oestrogen is involved in bone health. For women, osteoporosis risk is higher because of the sharp drop in oestrogen that comes with menopause.
Gender Females are four times more likely to get osteoporosis than men as women have smaller and thinner bones compared to men. However, osteoporosis does not just affect women and men can be affected too. Also, post-menopausal white woman are the most prone to osteoporosis (see below).
Genes              A family history of osteoporosis is a significant risk factor, with about 30 genes associated with osteoporosis already identified by the scientific world.
Being thin or having a slender frame   The smaller your frame the more likely you are to have fractures
Race                 While osteoporosis can occur in all race groups, white (especially Northern European) and Asian populations are at a higher risk to black and Latin populations.

Risk factors that can be changed
It is good to know that despite there being some factors that cannot be changed, there is still much that can be done to help prevent or at least delay the onset of osteoporosis. 

Low calcium and vitamin D intake                    Calcium is important to build stronger, denser bones early in life and to keep bones strong and healthy later in life. About 99 percent of the calcium in our bodies is in our bones and teeth. When we don’t get enough calcium for our body’s needs, calcium is taken from our bones.

Getting enough calcium is essential for bone health as calcium is the building block of bone. Vitamin D is also involved in bone health as it helps the body to use the calcium more efficiently. Good food sources of calcium include low-fat or non-fat dairy (milk, yoghurt, cheese), dark green leafy vegetables (e.g. broccoli, cabbage, collard greens, turnip greens, kale, okra, mustard greens), oranges, baked beans, oatmeal, almonds, sardines and pilchards (eaten with bones), clams, oysters, and salmon. 
The amount of calcium needed from a supplement depends on the amount of calcium you get from foods. If you get enough calcium from the foods you eat, then you don’t need to take a supplement. Use a calcium supplement if dairy product intake is not tolerated or sufficient. Some people who are lactose intolerant can manage eating yoghurt with probiotics and hard cheeses like cheddar and Swiss. 
Dietary supplementation of 1200mg of calcium and 800-1000 IU of vitamin D reduces bone loss and the incidence of bone fractures.  Post-menopausal women need a supplement of 1500mg per day. When you do take a calcium supplements, do so with food. It is not advisable to take more calcium than you need in supplements as there are some health risks such as kidney stones.

Poor fruit and vegetable intake             A good intake of fruits and vegetables is associated with a decreased risk of osteoporosis. Aim for a 5-a-day intake of fruits and vegetables to ensure good vitamin C, magnesium and potassium intake, other nutrients which are important in bone health.
Vitamin C is involved in the production of collagen, a protein which supports healthy bone structure. Be sure to include good sources of vitamin C in your diet such as citrus fruits, kiwi, strawberry, sweet peppers and tomato. Sources of magnesium include spinach, beet greens, okra, tomato products, artichokes, potatoes, sweet potatoes, collard greens and raisins.  Potassium-rich sources include tomato products, raisins, potatoes, spinach, sweet potatoes, papaya, oranges, orange juice, bananas, plantains and prunes. 

Too much sodium                    Eating foods that are high in salt (sodium) causes your body to lose calcium, even more so when calcium intake is low. Limit your salt intake by adding less salt to your food and decreasing take-aways and ready-prepared/processed foods.
Large caffeine intakes Coffee and tea naturally contain caffeine, and caffeine may hamper calcium absorption. For those at an increased risk for osteoporosis large caffeine intakes affect bone mass density. However moderate amounts of caffeine will not affect bone health. Limit to 3 cups of coffee per day and 5 servings of caffeinated soft drinks and teas. 

Too many soft drinks Some studies suggest that colas, but not other soft drinks, are associated with bone loss. The carbonation in soft drinks does not cause any harm to bone. The caffeine and phosphorous commonly found in colas may contribute to bone loss. Like calcium, phosphorous is a part of the bones. The harm to bone may actually be caused when people choose soft drinks over calcium-rich drinks such as milk.

Alcohol and smoking   High intakes of alcohol are associated with a lower bone mass density. Also, excess alcohol intakes are generally accompanied by a poor diet (such as a poor calcium intake) as well as cigarette smoking. Also, alcohol impairs normal functioning, making you more likely to fall and break bones. Limit your alcohol intake to one drink per day for woman and two drinks per day for men.

Cigarette smoke inhibits the activity of osteoblasts, the bone cells responsible for building new bone. It is therefore advisable to quit smoking not only to lower osteoporosis risk but to improve health overall.

Obesity            It is advised to maintain a weight within a healthy BMI range. When starting any weight loss regimen, be sure to include sufficient protein, calcium vitamins and minerals.

An inactive lifestyle      Just as muscles get stronger with exercise so does bone become stronger and denser with physical activity. Do weight-baring for about 30 minutes most days of the week and muscle-strengthening exercises two to three days per week.

Weight-baring exercise includes dancing, running or jogging, walking, aerobics and tennis. However, avoid excessive weight-bearing exercise which can lead to constant damage to bone. Muscle-strengthening involves exercises where you move your body or weight against gravity, such weight lifting. Stretching exercises and exercises that improve balance and posture such as yoga or Pilates are also beneficial. However, certain positions may not be safe for people with osteoporosis. If starting a new exercise routine, be sure to check with a healthcare professional and make your personal trainer aware of your condition.

Today we know a lot about how to protect our bones. Getting enough calcium, vitamin D and regular exercise are important for healthy bones, as is eating fruits and vegetables. On the other hand, eating poorly, smoking, drinking too much alcohol and not exercising is bad for bone healthy and may cause osteoporosis. You’re never too young or too old to improve the health of your bones, so adopt healthy habits now and take action in the prevention of osteoporosis.

References

1.       Escott-Stump, S. Nutrition and diagnosis-related care. 2008. 6^th Edition. Lippincott Williams and Wilkins.

2.       Mahan, LK and Escott-Stump, S. Krause’s Food and Nutrition Therapy. 2008. 12^th Edition. Lippincott Williams and Wilkins.

3.       National Osteoporosis Foundation. www.nof.org. Accessed on 27 October 2011.

     Article written by Monique dos Santos  (RD) SA  - Dieticians at work