EAST RUTHERFORD, N.J. – Seattle Seahawks linebacker Malcolm Smith won the MVP award at Super Bowl XLVIII on Sunday night, but that won't go down as his greatest achievement.

For Smith, just being in football's biggest game, just having a pro career at all, is a remarkable feat after overcoming a rare and debilitating illness that makes eating food and keeping it down a daily struggle. Smith suffers from achalasia, a condition that affects around 1 in 100,000 people and causes those afflicted to throw up food mid-meal unless it is consumed at an extremely slow pace and with a special chewing technique.

The 24-year-old contracted the condition while at USC in 2009. It caused his weight to plummet by more than 30 pounds and threatened his NFL prospects.

"He has fought and battled through a lot of things that a lot of guys may not have battled through," said his brother, Steve Smith, a wide receiver who won the Super Bowl with the New York Giants in 2008.

"It is hard. I watch him eat and I am worried about him. He has to swallow differently, he has to chew his food more, drink a lot, take a sip every time. It is not like you and I eat and drink our food. You can see him sort of regurgitating his food a little bit and swallow it back. It is not a comfortable or fun thing. He has tubes inside his body and it is so tough.

"He deserves this more than anyone and the way he has come through it is his greatest achievement. It is inspiring."

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Smith picked off Peyton Manning at 3:32 in the second quarter and ran it back for a 69-yard touchdown – to make the score 22-0. He swooped to grab the ball after Cliff Avril hit Manning and sprinted for what was the longest interception return in a Super Bowl since Tracy Porter of the New Orleans Saints returned a Manning throw for 74 yards to change the face of Super Bowl XLIV.

In the second half Smith recovered a fumble from Demaryius Thomas as the Seahawks strolled to a resounding 43-8 victory at MetLife Stadium.

Smith often eats his meals away from his teammates after training and separately from his family at home because he is embarrassed by the length of time it takes him. He is prevented from eating certain foods, such as rice, tuna and peanut butter, and needed an array of medical tests to figure out his ailment during his time with the Trojans.

However, his condition has not stopped him from being part of some of the most significant moments in Seahawks history. Remember, it was Smith who grasped the interception from Colin Kaepernick in the NFC championship game; you know, the one that followed Richard Sherman's leaping tip and before the rant that transfixed a national audience.

"I never wanted my condition to be something that would affect my career," Smith said. "I was fortunate to be around great doctors who have helped me come through it and I am grateful and thankful for this."

Smith is one of the unsung heroes of Seattle's domineering defense and by helping Pete Carroll's team earn the title of world champions he became part of the seventh pair of brothers to win a Super Bowl.

"He is just one of those solid guys who is always there and always works hard," said teammate Russell Okung. "You can tell what a strong character he has and his illness is proof of that. It is something he has been struggling with for a long time but the way he is able to come back and prepare himself for games is great."