Dr. David Rahm encourages his patients, clients, and readers to follow the 80/20 rule.  Basically, instead of having some hard and fast diet that you stick to to the death (and then when you mess up one time you completely cave in and fall off the wagon) to basically make margins for not being so strict on yourself.

In line with the post on lifestyle changes, as you are “dieting” through this contest, try to stick to your principles 80% of the time.  the other 20%, don’t go crazy, but give yourself a little breathing room.  Your results will be FAR BETTER than going 100% for 10 weeks then back to hardly any principles after that.  It is much better to each well four out of 5 meals, or 4 out of 5 days, then on the off day or that off meal, in moderation, treat yourself to a reasonable amount of something you like.

Blessings on Your Journey!