Dr. Christof (Christoph) Koch

But one of the big one is loss of autonomous play.

When is the last time you heard someone say, oh, yeah, I sent my kid outside.

I haven't seen her for three hours, but, you know, it's not dinner yet.

Well, that's how I grew up.

You send out the kids and they come back.

Today, that's utterly impossible.

I mean, you know, there are these cases where parents get arrested because their 12-year-old was walking to the store by themselves.

Well, so if you don't give kids, you know, if there's constant helicopter parents and having, oh, my God, don't do this, don't do that, you know, this is not good for you.

This is a big driver.

Social media is definitely a big driver, partly because of all these filters.

So you always compare yourself.

You know that your friends put their pictures on also through filters, but that's very easy to forget.

And you see these perfect pictures.

Pictures of everyone else, and you look at yourself, you don't look anything like this.

Oh, my God, there's something wrong with my body.

And then, of course, the pandemic has made it worse because people had to stay home.

I mean, it's certainly worldwide in all the advanced economies.

So this is in Europe, in Asia.

The other big driver is, I think, although no one studies this, probably for, well, I'll leave it to you, family size.

It used to be...