Losing the baby fat

The issue: Somewhere between the ages of 4 and 6, most children have lost their baby fat and are as skinny as they’ll ever be.

Why it matters: Parents sometimes respond by prompting the child to eat well beyond satiety. That forms an image of their child as skinny, which persists well beyond the age when natural weight gain has made it inappropriate. Parents may need reassurance that this “skinny age” is natural, appropriate, and typical.

Starting the conversation: “When you look at photographs of yourself growing up, when do you think you were skinniest? How old were you when you started to put on a little more weight? Does your child take after you, do you think? Most children are at their skinniest between the ages of 4 and 6, and after that they start putting more weight on. Some parents worry that their child is always going to grow up to be too thin. Do you ever worry about this?”

A third factor that may be operative has to do with maternal concepts of an ideal body type for a child. If her ideal body type is heavy, a mother may see her normal-weight child as needing to gain weight, and feed her or him accordingly. There are no strong data to support the notion that low-income or minority mothers prefer a heavier body type for children, however.

Pediatricians should also be aware that talk about growth charts, BMI, and percentiles may not be meaningful to many mothers. Several studies of low-income mothers report that they don’t understand growth charts, or think the charts have no relevance for their children.

“I don’t care what the growth chart shows. I know he’s too skinny!”

You pull the chart from the bin on the door for the next well-child exam. Jaden is a 5-year-old boy who has always been healthy, with attentive and conscientious parents eager to follow your every recommendation. You anticipate a smooth well-child visit, but sigh as you flip to the growth chart and note the pattern so many of your patients have taken on in the past 10 years. Jaden’s BMI has crept up from the 85th percentile to over the 95th, which puts him in the “overweight” category.

You prepare to discuss nutrition, exercise, and media exposure, and hope that since this family has so eagerly sought and followed your advice in the past, they will take your recommendations to heart. After catching up on events in the family’s life over the past year, you ask Jaden’s mother if she has any concerns she’d like to address today.

“He’s too skinny!” she exclaims. She recounts the concerns of both grandmothers that he is losing too much of his baby fat, and that he is thinner than most other boys in the neighborhood. She concludes by explaining to you that this is just not normal for their family, which is full of people who are naturally “big.” As you begin to explain the meaning of his BMI on the chart, she politely cuts you off and says, “Those charts just don’t apply to my son, doctor. I know my son and what he should look like, and he’s too skinny.”