At least, in everyday life it isn't--outside of the occasional "cheat day" on a diet.

FORBES: Magazine Article

Stick to a cheat meal, rather than a cheat day.

FORBES: Can Cheating On Your Diet Actually Help You To Lose Weight?

When you eat right for 6 days a week, one cheat meal on the 7th day will still allow you to reach your goals.

FORBES: Can Cheating On Your Diet Actually Help You To Lose Weight?

And I think until that day comes - that a Nike or whatever says no, you cheat, we will take away ever cent - I think we're going to continue to see cheating, unfortunately.

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