Dear Mr. Dad: My 7-year-old has always been a little chunky, but recently, his doctor said he was obese. I don’t want him to go through what I did in school, and I don’t want him to develop the health problems that come from being obese either. What can I do to help him burn some of that fat? Or is it just “baby fat” and he’ll burn it off as he goes through the next growth spurt?

A: Let me start with your last question: The baby fat excuse runs out of steam by around age two. After that, kids who are overweight or obese are at risk of becoming overweight and obese adults. So, while your son’s next growth spurt may slim him down a little, if your doctor says he’s obese, you’ve got a problem.

Before we go on, you deserve some sincere congratulations. First, recognizing that your son is overweight is, well, huge. A number of studies have shown that as many as 80 percent of parents with an overweight child believe the child’s weight is fine. And over half of parents of an obese child (one who weighs at least 20 percent more than the recommended number) don’t see their child’s weight as an issue.

Being overweight is seen as a kind of new normal, and when compared to the images of obese people we see so much in the media, a lot of parents say their child doesn’t look so bad.

Second, you may not realize it, but you did a great job selecting your son’s pediatrician. A lot of doctors, perhaps bending to a kind of political correctness, don’t use the words “overweight” or “obese” to describe children. However, parents whose doctors talk to them directly about their children’s weight problems are less likely to be so blind to those problems.

Sounds like you know about the physical health risks of obesity. But for those readers who don’t, here’s a one-sentence review: Overweight children are more likely than normal-weight kids to develop high cholesterol, high blood pressure, Type 2 diabetes (formerly called “adult onset”), heart disease, or have a stroke.

You mentioned that you don’t want your son to go through what you did in school. Overweight kids are more likely to be teased and bullied, and because they’re often unable to play with other kids, they can face a lot of social isolation, which in turn can increase the risk of depression and anxiety.

So what can you do? Start by asking the pediatrician to do a complete physical—obesity can sometime be caused by a medical condition. If there’s no underlying problem, there are really only two ways to help your son: reduce the number of calories he eats and increase the amount of physical exercise he gets. Our kids learn a lot from watching—and imitating—our behavior. If your son has a weight problem, there’s a pretty good chance that it’s at least partly caused by habits he learned at home. The solution is to lead by example: you’ll have a tough time convincing your son to make changes in his life that you’re not willing to make.

Leading by example also means that everyone in the family will make the same changes your son does. Singling him out as the only one with a problem could make him rebel by putting on even more weight. Plus, eating better and doing exercise together is not only good for you physically and mentally, it can also bring your family closer together.