Ask any new parent how their baby is doing and you will most likely get an update on recent weight gains.

Regular baby weigh-ins are a rite of passage, but many parents look back at this time with a deep sense of failure; when told their child isn’t “gaining enough,” they’re left feeling like they didn’t try hard enough with this whole feeding business.

Numbers on the scale have become a defining measure of an infant’s progress. And the message given to parents is that more weight gain is better.

But this is not how percentiles work. By definition, half the population has to be above the 50th, and half below. There will always be infants who track in the third percentile and some in the 97th. This is OK.

Mothers reported insisting their toddler eat despite not being hungry, using desserts as a bribe to get the child to eat the main course, and showing disapproval when the child did not eat.

We want children to eat because they are hungry, not to keep us happy. Eating for reasons other than hunger leads to overeating and overweight.

Our love of chubby babies makes a lot of sense. Most of human history has been a time of food scarcity. Extra weight, especially in infancy, conferred a survival advantage.

But today, our children are born into an “obesogenic environment,” where unhealthy food is cheap and readily available, and our surroundings encourage us to move less and sit more. It’s really hard not to put on weight.

If and when this information is incorporated into the guidelines, there is no comprehensive method of informing practitioners what has changed and no way of measuring whether guidelines are implemented.

Practitioners can continue to talk to parents about what normal child growth looks like at any percentile, and to monitor growth—not just weight.

Most importantly for parents, if someone says your baby is not gaining enough weight, question it. Ask them to explain what criteria they are using to make that judgment and how they can help you comprehend those charts.

I love a chubby baby too. But I love a baby who tracks on the same percentile over time for their weight, length, and head circumference, even more.

Rebecca Byrne is a dietitian and research fellow at Queensland University of Technology. This article was originally published on The Conversation.