eli5: why do babies appear to be fat?


Why do babies when born, appear to have a lot of fat along their arms, legs, and chest?

In: Biology

It’s a combination of fat and loose skin. They have a lot of growing to do and store a lot of calories.

Human babies have the highest percentage of body fat at birth compared to all other land mammals, peaking around 25% at 9 months.

The closest other mammals are seals and guinea pigs.

A lot of the fat mammals put on weight quickly but aren’t born as fat as humans.

The fat insulates as well as providing energy for a power hungry brain.

Because they are. The first commenter said it best but also beast milk often doesn’t come through properly for a couple days so babies are born a bit chonky to compensate for this.