Building healthy bones

Regular exercise and good nutrition can help you live a long, healthy life.  But if you’re not paying attention to your bones, life could be very uncomfortable.

Osteoporosis, a disease characterised by low bone mass and structural deterioration of bone tissue, is a major threat for 28 million Americans.  

According to Dr Bill Robertson, Internal Medicine and Pediatrics: "Bone is living, growing tissue.  Throughout life, old bone is removed (called resorption) and new bone is added to the skeleton (called formation).  During the childhood and teenage years, new bone is added faster than old bone is removed – making bones heavier, larger and denser.  Most people reach peak bone mass during their mid-20s. And after the age of 30, the removal of old bone begins to exceed the formation of new bone."  

That’s why it’s important to get your teenager on the path to healthy bones early. 

Osteoporosis can be prevented

Robertson continues, "Osteoporosis develops when bone loss occurs too quickly or if replacement occurs too slowly and is most likely to occur if you don’t reach optimal bone mass during your younger years.  It’s often called the "silent disease" because bone loss may occur without symptoms.  People may not realise they have the disease until a sudden strain, bump or fall causes a hip fracture or a vertebra to collapse."  

Risk factors

Among the specific risk factors for osteoporosis, there are some that can be changed and others that cannot.

Here’s what cannot be changed:

• Gender: Since women have less bone tissue and lose bone more rapidly than men because of menopause, they are more likely to develop the disease.
• Age: It can lower bone density and strength. The older you are, the greater the risk.
• Body size: Small, thin-boned women are at greater risk.
• Family history: People whose parents have a history of fractures may also have reduced bone mass and may be at risk.  

Risk factors that can be changed:  

• Sex hormones: This includes an abnormal absence of periods, low oestrogen levels and low testosterone levels in men.  Your doctor can help evaluate your hormone levels and provide treatment when necessary.
• Anorexia
• A diet that is low in calcium and vitamin D.
• Use of certain medications, such as glucocorticoids (prescribed for a wide range of diseases, including arthritis, asthma, Crohn’s disease, lupus and other diseases of the lungs, kidneys and liver) or some anticonvulsants.  Be sure to discuss use of these medications with your doctor before you alter your dosage on your own.
• An inactive lifestyle or extended bed rest.
• Cigarette smoking.
• Excessive use of alcohol.  

Prevention

There are several steps that can help your teenager’s body reach optimal peak bone mass and continue building new bone tissue as she gets older:  

• Calcium: Studies have shown that low calcium intakes can be associated with low bone mass, rapid bone loss and high fracture rates.  Many people consume less than half the amount of calcium recommended to build and maintain healthy bones – 1000/mg a day for women and men between the ages of 25 and 50.  Good sources of calcium include low-fat dairy products (milk, yoghurt, cheese and ice cream), dark green leafy vegetables (broccoli, collard greens, bok choy and spinach), tofu, almonds and foods fortified with calcium, such as orange juice, cereals and breads.  Depending on how much calcium you get with your regular diet, a calcium supplement may be needed.  
• Vitamin D: This vitamin plays an important role in the absorption of calcium and in bone health.  It is synthesised through the skin through exposure to sunlight – so Vitamin D production tends to decrease in the elderly, the housebound and during winter.  
• Exercise: Bone, like muscle, responds to exercise by becoming stronger.  Good exercises include walking, hiking, jogging, stair-climbing, weight training, tennis and dancing.  
• Smoking: It’s as bad for your bones as it is for your heart and lungs.  Women who smoke have lower levels of oestrogen compared to nonsmokers.  
• Alcohol: Regular consumption of two to three ounces a day of alcohol may be damaging to the skeleton, and those who drink heavily are more prone to bone loss due to poor nutrition as well as increased risk of falling.  

If you suspect that you or your teenager may have complications from bone loss, or have one or more of the risk factors mentioned above, see a doctor for a comprehensive medical assessment.  This includes a test that can detect low bone density and determine rate of bone loss.

(Source: University Medical Center: February 2009)