Back in the day, scientists Kevin Hall had a vice.

Yeah, unfortunately, way back when I was kind of addicted to reality television and a friend of mine said,

you've got to watch this show. This is like right up your alley.

No matter who they train with, their lives will be changed forever.

And so I turned it on and saw this kind of horror show reality program where people are getting sort of yelled at on treadmills.

Here we go!

But only one will become the next biggest reason.

Yeah, the biggest loser, that long-running, heavily criticized TV show.

Basically, it showed contestants with obesity competing to see who could lose the most weight.

And we're talking, like, 100 pounds or more.

They went on really restrictive diets and took up hard core exercise routines.

Now, a lot of people think this show was the epitome of everything that's wrong with diet culture.

It showed people pushing themselves to unhealthy limits to lose weight.

And then it celebrated those losses as if they were the most important thing they'd ever achieve.

And Kevin was horrified, too.

But he studies metabolism.

So he also had questions about what was going on with their physiology.

The thing that kind of caught my attention was the fact that these people were losing so much weight so quickly.

And that didn't mesh with what I knew about weight loss and how difficult it is.

And kind of struck the question of, you know, what's going on inside the bodies of these people?

So Kevin decided to do a formal study looking at contestants from one season of the biggest loser.

Many of them had gained most or all of the weight back.

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