Americans don't choose to be fat. Many live within a 'system they don't control.'

Part 4 of a six-part USA TODAY series examining America’s obesity epidemic.

Nathaniel Louis Brown always loved his food, especially spaghetti and potatoes. On a typical night, he would eat three dinner-plates full. On holidays, Brown, 64, served himself on a platter.

He knew he should cut back, but he didn't have anyone who cared enough to tell him to eat less. Plus, food helped him curb life’s stresses and his constant worry. 

Then came the heart attack.

Brown's life is far from perfect, but he wasn't ready for it to end.

"I want to try to live up to 100, 120. I know that ain't going to happen, but that sounds good to me," said Brown, a former long-haul truck driver, factory worker and prison guard now living in Indianapolis.

The social, racial and economic inequities that people like Brown face help explain why the nation's obesity epidemic remains so challenging.

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(Photo: NiCole Keith)