Conversation

Doctors think that telling people the facts will prompt them to change their habits.

Hahahaha! That's so adorably naive.

Make reasonably healthy food cheaper, tastier and more convenient to buy than junk, and people will buy less junk. Make exercise more enjoyable than sitting on your bum and people will exercise more.

This is impossible, of course. Eating chocolate and sitting on your bum will always be more pleasant than eating carrots and taking a run.