Pollution & bones

weakening

Much has been written and talked about the ill-effects high levels of air pollution have on our collective respiratory health.

Increased incidence of respiratory disorders such as asthma, COPD, bronchitis, even lung cancers are today associated with constant exposure to polluted chemical-laden air. However, do you know, the same air pollution that is damaging your lungs might also be having harmful effects on your bone health?

A number of studies in recent years have highlighted that air pollution doesn’t just impact the respiratory system but can have lasting effects on other systems of the body as well. Exposure to air pollution contributes to cardiovascular illness.

The American Heart Association states that short-term exposure can increase the risk of heart attack, stroke, arrhythmia and heart failure in vulnerable people, such as the elderly or those with pre-existing medical conditions. 

Risk of arthritis & osteoporosis

Several studies have suggested that exposure to air pollution also causes systemic inflammation and chronic inflammatory diseases such as rheumatoid arthritis. At the same time, a series of independent studies in different parts of the world have also succeeded in establishing a link between air pollution and sustained loss of bone minerals, resulting in osteoporosis.

According to facts cited by the International Osteoporosis Foundation, osteoporosis causes more than 8.9 million fractures annually worldwide, accounting for an osteoporotic fracture every three seconds. One in three women over age 50, while one in five men aged over 50 are likely to experience osteoporotic fractures.

More rampant in women than in men, osteoporosis or brittle bone disease is estimated to affect 200 million women worldwide. A 10% loss of bone mass in the vertebrae can double the risk of vertebral fractures, and similarly, a 10% loss of bone mass in the hip can result in a 2.5 times greater risk of hip fracture. The figures reveal that osteoporosis is a widely common condition with a massive health burden across the world.

Clinical evidence suggests that osteoporosis is rampant in India. In fact, over the past two decades we have witnessed a downward shift in average age of patients being diagnosed with osteopenia and osteoporosis – the progressive manifestations of brittle bones.

How are bones affected?

The relationship between air pollution and bone health is complex and multi-pronged. We know fairly well that tobacco smoke directly induces systemic damage in the body that interferes in absorption of bone minerals and causes low bone density as a result.

At the same time, patients with chronic obstructive pulmonary disease (COPD) are seen to have a high risk of developing osteopenia and osteoporosis. Air pollution, on the one hand is believed to induce tobacco smoke-like changes in the body; on the other it also causes chronic obstructive pulmonary disease which leads to reduced lung function. Compromised lung function is associated with increased levels of systemic inflammation which is yet another risk factor for osteoporosis.

Another explanation derives from how prevalence of pollutant particles in the environment obstruct a large amount of UV radiation from reaching the earth’s surface. Now, the synthesis of vitamin D in the human body takes place when the skin is exposed to UV radiation. Vitamin D controls calcium levels in the blood and helps maintain healthy bones, muscles and teeth while also regulating other aspects of general health. When human body is not exposed to sufficient UV radiation, vitamin D deficiency is a natural consequence. This deficiency serves as a major cause of body’s inability to absorb sufficient calcium and a resultant low bone mineral density.

How to limit the impact

While it is practically impossible to pack up our lives and move to the countryside to avoid air pollution, some small steps can be taken to minimise the impact.

Drink sufficient water everyday to help your system get rid of the pollutants accumulated due to constant exposure.

Consuming liver-friendly foods such as carrots, lemons and bitter greens.

Cinnamon, ginger and turmeric help the body fight inflammation.

Ensure sufficient intake of calcium in the form of dairy products. If needed, talk to a doctor about supplementation. This is especially recommended for post partum and post menopausal women

Spend some time under the sun daily and undertake regular exercises to strengthen the bones.

(The author is consultant joint replacement surgeon, Indian Spinal Injuries Centre, Delhi)