The conversation parents dread even more than the one about the birds and the bees? It’s the one about their kids’ weight.

Sure, the facts-of-life talk is awkward and needs to be age-appropriate and you want your facts straight, but it’s different when you’re talking to your kids about what they weigh. Your children never view such talks as positive, only as being about what’s “wrong” with them. But you can have this talk without damaging your children or your relationship with them.

The one thing you never want to do is tie weight to the children’s appearance or “acceptability.” I recently saw an obese 8-year-old and we discussed the health issues related to the child’s weight and some easy ways to get started changing her diet and lifestyle. Her mother then told the girl, “If you lose weight you’ll be so pretty and I’ll buy you lots of pretty clothes.” I halted the conversation and told the mother that her daughter was already pretty and that I just wanted her to be healthier and feel better, and that that was the point of changing her diet and lifestyle. I then spoke directly to the girl and told her the same thing.

It cannot be emphasized enough: this is a health issue, not a cosmetic one.

Here are some other critical things to remember before even considering discussing body weight with your child.

First, make sure there’s a health or medical issue that needs to be addressed. There’s a healthy and normal weight range for a child’s height: the body mass index, or BMI. It’s not a perfect measure of overweight and obesity, but your child’s pediatrician or health professional can determine the BMI and put it into context for your child.

Another issue is you. If the child’s BMI is within normal range but you want the child to lose weight, then your child’s pediatrician may need to have a talk with you about you, not your child. Children should never have a reason to feel they are not loved or accepted by a parent because of their weight. On the contrary, it’s often a good idea to clear the air about this right at the start of the talk and repeat it a few times during and afterward, to reinforce the importance of the health aspect.

Usually when I see overweight children, there’s at least one overweight parent. Studies and statistics bear this out, too. Whether this is due to genetics or the home environment has been debated by my colleagues for decades; when it comes to treatment, it likely doesn’t matter so much.

Permanent solutions require permanent but gradual changes. This is where there’s an opportunity for you really to do some good. If a parent is overweight or obese, it’s an ideal time for the parent to make his or her own diet and lifestyle changes. When kids hear “We’re going to do this together,” it becomes not “their” issue but “our” issue, and they feel supported, not isolated. Then kids will likely see the parent as an advocate, not an authority figure.

Changes in how the family approaches food, eating and lifestyle don’t need to be made suddenly. Indeed, if changes are to be permanent, they really should be made gradually and persistently.

Food often spells comfort for children and adults, and both need to understand that it’s not about “good vs. bad” foods, but about “how much and how often” they’re eaten. You can seize the opportunity to leverage the healthful foods the child may actually like and let the child know that those foods will be around a lot more.

Talking about physical activity can be especially touchy. Overweight kids can be teased and bullied about their weight and may have had negative experiences with team and organized sports. Let them know that becoming more active is also a gradual process and there’s no need to run marathons, start martial arts or join Little League, unless they want to. Getting the child an inexpensive pedometer to track his or her steps each day, however, is a good move, and the proof of activity is something kids love. Adding 2,000 steps a day is equivalent to about a mile, and simple nonfood rewards for achievement can maintain motivation and compliance.

Involving children in each aspect of the family changes can inspire success. Making them a part of the process just underscores that they’re important members of the family who deserve to have some say about how they achieve success. When parents see their children adapting well to the changes in their diets and lifestyles, praising the children is an absolute must. The only thing kids like more than achieving a goal is being told by their parents that they did a good job—and that isone talk all parents want to have with their kids.

Keith-Thomas Ayoob is director, nutrition clinic, Children’s Evaluation and Rehabilitation Center, Albert Einstein College of Medicine. He blogs at The Doctor’s Tablet.