The real problem is that the human body is not designed to function optimally in an environment where food is so plentiful.

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That in turn increases both the amount of fluid and the movement of food in the intestine, helping it function better.

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But the Food and Drug Administration does not prospectively review food claims because American law says that foods are allowed to affect the "structure and function" of the body, so long as they do not actually claim to treat disease.

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