Say you're eating lunch with a friend who's overweight. She's sipping a Diet Coke while dousing her salad in gobs of Ranch dressing, croutons, and shredded cheese. Would you politely offer some tips about how to make her meal lower in calories, or would you keep your mouth closed? Offering health and fitness advice is a tricky thing. There's a fine line you can cross over, where you end up hurting her feelings instead of helping her become healthier.

Is it your duty to spread the word of health and fitness to the world, or are you careful about who you spread the word to?

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