By John Dodge

CHICAGO (CBS) — Celebrity chef Graham Elliot decided he needed to do something when he was having trouble tying his shoes and playing with his children.

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Elliot, owner of Graham Elliot Bistro and star of “Master Chef,” weighed 405 pounds.

So, eight months ago, he had gastric sleeve surgery at the University of Chicago.

He has since shed 150 pounds–or about 63 percent of his body weight.

The surgery involves removing a significant portion of the stomach, turning it into a thin sleeve.

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The concept seems simple: A smaller stomach means patients feel full faster when they eat.

However, the surgery cannot be reversed, and patients must adhere to a healthy diet to avoid complications.

He tweeted this pictures in December, and he has since lost another 20 pounds.

Elliot explained his decision to have surgery, rather than try to lose the weight only by dieting.

“You can keep saying, ‘Well, you’ve got to do it the real, old-fashioned way,” he told MSNBC last month.

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“‘You’ve got to do it on your own. The surgery is the easy way out.’ But again, when you get to 400 pounds and you have a family to look after, you realize, that’s all ego. You can try to do it on your own, [but] if you don’t get the results, you’ve got to do whatever you’ve got to do.”