Nature deficit disorder is a phrase coined by Richard Louv, who wrote a book called Last Child in the Woods in 2005 that brought a lot of this stuff together. I've worked with Rich for the last five years as part of his strategic planning committee in the U.S.
I'll throw some stats out. Right now the average screen time for an 8- to 18-year-old in North America is 52.5 hours per week. That's average. That means that there are a lot of them who hit 70, and there are a few who hit 30. The Kaiser Family Foundation did this stat two years ago. They didn't believe the stat when they did it, so they tested again with thousands more people, and they ended up with a bigger number.
What happens? What happens is the difference between the kids who hit 30 hours a week as their average screen time versus the kids at 70. What's different between them? There was one specific question that they addressed—one thing, one statement—that they had that was different. It was that almost all of the ones in the 30 range—94% of them—could remember a moment before they were eight years old when they had an immersive, important, life-changing, memorable experience in nature with a grown-up. For the ones at 70, the numbers were around 40% to 45% of them.
There is something significant that happens. In some of the research, they talk about how it's akin to imprinting, just like a duckling imprints. We imprint on this stuff. Right now, we're working awfully hard as a society to make sure that they don't have that moment when they imprint on nature.
What does 40 hours a week mean in terms of health and well-being—40 hours a week of not being in front of a screen, but actually 40 hours more of engagement? It means they're not going to be obese. This is the first time in history when we, as the grown-ups around this room, are going to have a longer lifespan than our kids.
They are going to die faster, they are going to cost more, and that's the big change. That's the big payoff. It saves us loads of money. There can't be an easier intervention: go outside.