Due to advances in medicine, improved access to health care and healthier lifestyles, the average life expectancy of Canadians reached 81.7 years in 2011.

But while life expectancies continue to climb, "healthy life expectancies have improved very little," says Aileen Burford-Mason, a Toronto-based immunologist, cell biologist and nutritionist. The author of Eat Well, Age Better (Dundurn, 2012) attributes this to the rise in chronic degenerative diseases, such as diabetes, heart disease and liver disease. What’s more, many of these chronic illnesses are seen at increasingly younger ages, which is why the current generation of Canadian children may be the first in our history to have shorter life expectancies than their parents.

Dr. Jill Hamilton, staff endocrinologist and head of the Centre for Healthy Active Kids at The Hospital for Sick Children in Toronto, believes the biggest health risk facing Canadian kids is Type 2 diabetes,  a condition that she says was "unheard of in children before the 1980s." Children who are diagnosed with Type 2 diabetes can experience complications from the disease, such as kidney failure, amputation and stroke, which can occur early in adulthood. Another health issue plaguing kids is excess weight: One in three Canadian children is overweight or obese. "Over the past 10 years, we’ve been noticing that complications related to  excessive weight gain can occur during childhood," says Dr. Hamilton. "These complications can be life-threatening and certainly shorten life span."

Dr. David Agus, professor of medicine and engineering at the University of Southern California and director of USC’s Norris Westside Cancer Center and Center for Applied Molecular Medicine, believes we need to start taking ownership of our health to enjoy longer, healthier lives. "It’s possible to prevent or delay most illnesses that develop over time, including cancer and heart disease," says the author of The End of Illness (Free Press, 2012) and A Short Guide to a Long Life (Simon & Schuster, $21).

Burford-Mason agrees that it starts with disease prevention. "We have to put preventive health back at the centre of our lives." The good news is that it’s never too late to turn back the clock. "You can start improving your health at any time, because the body is continuously self-renewing," she says.

So how can you tip the scales in favour of a longer, healthier life? Burford-Mason believes feeding our bodies properly is the key to maintaining them over the long haul. "You can start to nourish your body properly at any age and see benefits." While there’s no nutritional magic bullet, studies have shown that an increased consumption of fruits and vegetables can help you live longer. "There is strong evidence that when fruit and vegetable intake goes up, all-cause mortality—which means dying from any cause—starts to go down," says Burford-Mason, who advises her patients to make sure they get at least 10 servings a day.

Dr. Agus sees physical activity as "the only proven fountain of youth." He advises his patients to fit in aerobic exercise and to get moving consistently. At the very least, that means taking a five-minute walk for every 45 minutes of sitting. "The key to health is not just exercise, it’s movement over time," says Dr. Agus. "It’s great if you go to the gym for an hour, but if you sit for five hours straight, that’s as harmful to your health as smoking a pack of cigarettes."

Dr. Agus also champions the adage, "Know thyself." He’s a big fan of activity trackers, which can provide a realistic picture of movement levels throughout the day. He also advises patients to "get naked" regularly, look in the mirror for changes in their bodies and bring up any issues with their doctors. "All too often, we forget to really listen to what our bodies are saying," says Dr. Agus.

Eating 10 servings of fruits and veggies a day and giving up Netflix marathons? These are tough pills to swallow. But implementing healthful habits today is the only way to prevent illness later. "Some patients tell me they’re too busy to change," says Burford-Mason. "I tell them the alternative is finding time to be sick."

Check out how you can add more fruits and vegetables to your diet.

This content is vetted by medical experts

This story was originally titled "Living Better" in the November 2014 issue. Subscribe to Canadian Living today and never miss an issue!