The focus of much of my work as a physician is to help my patients live long, healthy lives. This involves the prevention of injuries, diseases and their complications.

Yet my work has taught me that life is precarious. We can consider ourselves perfectly healthy today, but we could be injured or die in an accident at any time. Even if we've been feeling perfectly fine, we can be surprised by catastrophic illness in the form of a stroke, heart attack or cancer.

If you were told you had only one year left to live, how would you plan your time? What if you had a few months or a few weeks? What would you do this day if it were your last?

These are sobering questions. Most people prefer not to think about their own deaths. We each want to think that the end of our lives is somewhere out there in the distant future. We go about each day as if tomorrow is guaranteed and we have all the time in the world to do what we need and want to do.

Some people are more fatalistic. They continue to smoke, abuse drugs and drink to excess, or they forgo regular exercise and healthy eating because thinking they will die anyway, they see no need to change. Of course, they simply increase the likelihood that they will become sick and disabled or die prematurely.

Some people ignore their family history, not realizing that some cancers, including those of the breast and colon, could be screened for regularly so that they may be detected and treated early and increase the odds of survival.

Others assume that premature heart attacks and strokes in their parents will doom them to the same fate. Yet this family history can be helpful; it alerts us to the need for the early detection and treatment of atherosclerotic risk factors, such as high cholesterol, blood pressure and diabetes.

My dad's mother died prematurely from the complications of diabetes. My own mother died suddenly and unexpectedly from asymptomatic heart disease. This family history has empowered me to be proactive in my own health.

I eat a low-fat diet, exercise at least an hour each day and pay attention to the glycemic index of my food.

Glycemic index refers to the ability of some carbohydrates, such as white rice, to raise your blood sugar more quickly than others, such as brown rice.

It is an important aspect of a healthy diet for people with diabetes and glucose intolerance or other risk factors for diabetes. Glycemic index is explained with examples in the book, The GI Diet, by Rick Gallop, and at www.diabetes.ca, the website for the Canadian Diabetes Association.

I also monitor my blood pressure and cholesterol levels to ensure they remain in a healthy, low-risk range.

A healthy lifestyle tailored to my hereditary risk factors helps me feel more empowered and engaged in my own health.

I'm controlling those factors that are under my control. However, I am not lulled into believing that I am guaranteed to live disease-free into old age. I know that accidents and illnesses may still strike at any time.

In my next column, I'll ask you and myself how we would live if we knew our time was limited.

Dr. Davidicus Wong is a family physician.