Adam Ruins Everything – Why Extreme Diets Don’t Work | truTV

artist’s rendering of what you
could look like. Huh? Inspired yet? Well, now,
that is… sexy. Yeah, I want to
look like that. Unfortunately,
it probably won’t last. In a few years, you could actually end up looking more or less
like you did before. Why?
Who are you? Oh, this is Dr. Kevin Hall. He’s an expert
on metabolism at the National
Institutes of Health, and he conducted
a six-year study of contestants
on “The Bigger Loser.” Hey, Sam,
while I can’t speak to how they produce
these shows, what I can tell you is
that of the 14 contestants that we studied,
80% of them regained most of the weight
that they’d lost. But why?
I don’t understand. When you work out,
you shed pounds. When you go on one
of these extreme diet
and exercise programs, your body doesn’t
have enough food
energy available, so it does burn
body fat. Right!
Very thin-spiring. Unfortunately, the body
soon lowers its metabolism to offset
that energy deficit. And that means
that you’d have to keep exercising and dieting
at this extreme rate just to maintain
the weight-loss. But on the show
we work out, like, 18 hours a day
and eat nothing. I can’t keep that up.
That’s impossible. Exactly. That’s why most
of the contestants we studied
regained the weight. Aah! Okay, all right! I’ll work
out this hard forever. Then will I stay thin? Not necessarily. One of our most surprising
findings of our study was that “The Biggest
Loser” contestants had slowed their metabolism by several hundred
calories per day, and that’s
even after they
regained the weight. So you’re telling me
that losing weight faster could make it harder
for me to stay thin? I’m afraid so. But Mandy said that
willpower was the key. Sam, if anyone
had willpower, it was the people
that I studied, and they showed that willpower
alone isn’t enough. In fact, research has shown
that genetics explains most of the weight differences
between people. So, as much as we
all want to be thin, we have to accept that
that might not be an achievable or realistic
goal for many of us. Now, who wants some fruit? (excited chatter) Bye, Dr. Hall! Whoa, whoa, whoa!
Hey, hey, hey! What’s goin’ on here?
Lunch is over! No, back to work.