One of the joys of being a grandparent is getting to see the world again through the eyes of a child. Recently, I found my three-year-old grandson picking at a scab on his arm. It brought a flood of memories because I used to do the same thing. It was amazing to watch the blood from an injury dry and, over days, form a scab. Before that scab was ready to fall off, I would pick at it to see what was underneath, and, wonder of wonders -- it was fresh, pink skin!

It's amazing how our bodies regenerate. We get hit and bruises form as blood leaks into tissues. Over time, the dark blue colour is diluted, and may move before disappearing. Even broken bones will heal and return to full strength. And skin, our largest organ, is a miracle layer. It keeps the rest of us inside and everything else outside. It wards off infections, sheds water, cools us in hot weather, and repairs itself.

Still, viruses, bacteria, and parasites are ever-alert for opportunities to penetrate our protective layer. As well as frequent nicks and cuts, we have natural openings like mouths, ears, noses, anuses, and genitals, each with its own protective mechanisms. If an invading organism gets inside, we have an incredible barrier, our immune system, constantly generating new proteins to fight off infections we've never even encountered. We have a defence system that recognizes and fights against any cell with a genetic makeup different from our own (which is why it's so difficult to transplant organs, tissues, or cells). Yet, pregnant women support a foetus that is genetically different for nine months.

Thanks to evolution, our bodies have powerful ways to ward off illness and infection and enable us to live long and healthy lives. Why, then, do health costs continue to climb at unsustainable and frightening rates? Part of it is that medical care has become so sophisticated that doctors are able to treat more problems. Another part is the ever-increasing cost of drugs. And with a medical system, people are more likely to seek help. Still, health-care costs can't continue to rise forever. Governments are always looking for ways to reduce costs, often by offloading a greater share of the burden onto patients.

We must pay greater attention to keeping our bodies and minds healthy and able to heal. Yet we are making it difficult for our defences to work. We allow things to be sold that should not be called food. Many have no nutritive value and lead to obesity, salt imbalance, and allergies.

We spew chemicals into the environment by the millions of tonnes. Molecules pour into us through air, water, and food, overwhelming or weakening our protective immune systems. According to Harvard University doctors Eric Chivian and Aaron Bernstein, "Our behaviour is the result of a basic failure to recognize that human beings are an inseparable part of nature and that we cannot damage it severely without severely damaging ourselves."

The medical literature tells us that the most effective ways to reduce the risk of heart disease, cancer, stroke, diabetes, Alzheimer's, and many more problems are through healthy diet and exercise. Our bodies have evolved to move, yet we now use the energy in oil instead of muscles to do our work.

In 2007, the World Health Organization concluded that environmental factors contribute to 36,000 deaths and 13 per cent of the disease burden in Canada annually. The Canadian Medical Association claims air pollution causes more than 20,000 premature deaths a year.

And according to author and environmental lawyer David R. Boyd, scientists estimate that environmental factors affecting heart and respiratory disease, cancer, and birth problems contribute to anywhere from 10,000 to 25,000 deaths, 78,000 to 194,000 hospitalizations, 600,000 to 1.5 million days in hospitals, and other problems totalling $3.6 billion to $9.1 billion in direct and indirect costs each year.

It's easier, more effective, and cheaper to let healthy bodies fight off disease and infections than to weaken those defence mechanisms and then compensate for them medically. If we want a stable health system, we must put more resources into reducing pollution and environmental degradation and creating a way of life that keeps bodies and minds happy and in good health.

Learn more at www.davidsuzuki.org.

For more insights from David Suzuki, please read Everything Under the Sun (Greystone Books/David Suzuki Foundation), by David Suzuki and Ian Hanington, now available in bookstores and online.

This Blogger's Books from

The Japan We Never Knew: A Voyage of Discovery
by David Suzuki, Keibo Oiwa

David Suzuki: The Autobiography
by David Suzuki