Unless New Zealand comes to grips with its epidemic of childhood obesity, you're certain to pay more for health insurance. You're likely to prematurely lose friends and family members to obesity-related diseases. You may know children who suffer the social stigma of being overweight and feel powerless to do anything about it.

The issue is not about looking pretty or handsome. It's about helping children stave off devastating diseases and the consequential loss in quality of life. It's about changing a cycle of behaviour that becomes more difficult to change as people become older. And it's about the health-care costs that we all pay.

In most cases, obesity is preventable. Habits can be changed, one step and one day at time.

Yes, genetics plays a role in obesity. But the greater impact comes from reasons that can be controlled.

Parents set a bad example when they plop in front of the TV after dinner instead of going for a family walk. Families give in to the pressures of society's fast pace and drive-through mentality; it's easier to grab a high-calorie meal at a fast-food joint than to eat a nutritious breakfast or dinner at home.

The symptoms of this obesity epidemic are evident everywhere. Few kids ride bikes to school anymore. Neighbourhood games of cricket, rugby and tag have largely disappeared. Kids rarely play sports unless they're on an organised team or in a physical education class. Even in P.E., many kids hang back because their weight makes them embarrassed or less able than other children.

Meanwhile, today's kids are drinking high calorie fruit juices, sodas and sports drinks. They're munching on lollies, fast foods and high-fat meals, despite living in one of the most productive fruit and vegetable farming regions in the world. And they're sitting in front of the TV or video game machine instead of getting exercise in the beautiful New Zealand outdoors.

Obesity is not an individual problem; it's a family issue. Don't waste your breath lecturing kids. Instead, set the good example and bring the kids along.

For starters, go for a walk with your kids, grandkids or other children. Start with five minutes a day if that's all the time or energy you have. Gradually add minutes and distance. Over time, you'll feel healthier and less stressed.

Something amazing will happen as well. You'll build stronger bonds with those children.