Each pre-teens eats about 49 pounds of sugar a year.

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Everyone knows Dr. Oz loves to bring props with him, but this time he didn't bring along a brain, a lung or a heart. Instead, he has a sobering reminder of the obesity crisis in America. Three huge jars hold 49 pounds of sugar—equal to the amount the average American pre-teen eats in a year. Eating this much sugar and other unhealthy things sets in motion a lifetime of health problems, Dr. Oz says.

"As you get older, the fat comes alive," he says. "It becomes a hormone secreting gland. They get acne because they're getting feminized, because those hormones are estrogen. [Boys] grow breasts, which hurts your self-esteem and scars you your whole life. And as you get older, you begin to develop fat around your jowls. Now you can't sleep at night because you've got sleep apnea, which is like having a bunch of rear-end collisions all day long."

That's not where it stops. Dr. Oz says an enlarged omentum squeezes the kidneys, leading to high blood pressure. It poisons the liver and leads to more bad LDL cholesterol. And it blocks insulin, which leads to diabetes. "The next generation will be the first that we know of in our recorded history that will have a shorter life expectancy than its parents," Dr. Oz says. "The major driver of that is the obesity that's causing diabetes. Almost a fifth of the kids in the country today are overweight. Thirty-five percent of the kids that are born in this decade will be diabetics. If you're black—40 percent of the kids. And if you're Latino, half the kids."