'GMA' Q and A: Ask Joan Lunden

May 3 -- Joan Lunden brightened the days of Good Morning America viewers for 17 years.

The former morning show anchor talked about her new book, Growing Up Healthy: Protecting Your Child From Diseases Now Through Adulthood, on GMA Monday. The book is chock full of information she's learned on the job — as a mother of five — over the years.

Read an Excerpt

Lunden also answered questions for an online Q & A on ABCNEWS.com.

Q: How do you help an overweight child lose weight without making them miserable, because all of his friends are eating what they want? — Gina, Hackettstown, NJ

A: It's tough to tackle the issue of a child's weight. You're to be commended for addressing the problem. The important thing to do in this situation is to sit down with your child and explain that he is overweight. Be very supportive and try not to be judgmental. Make it clear to him that by making some simple changes — cutting back on calories and exercising more — he can trim down and become healthier.

That doesn't mean doing without his favorite foods or not joining his friends at fast food places. It just means becoming informed and leaning to make better choices, like ordering the single burger instead of the double, substituting a salad for fries, and choosing water or juice over the milkshake. When it comes to diet and exercise, small changes can add up to big benefits.

Ironically, while peer pressure may be causing your child to make poor choices in some situations, your son's peers may also be making fun of him for being overweight. Overweight children and adults are one of the most discriminated against groups in the US. Explain this to your child, and help him see that better eating habits-eating a variety of healthy foods, making sure that trips to the fast food joint are considered a treat, and not the norm-are essential to his physical healthy and emotional well-being.

Q: What's the most important life lesson you've learned since leaving Good Morning America? — Emily, Long Beach Calif