I am on my fourth day of 21 trying the Virgin Diets cycle 1 where you remove the seven foods that can create intolerances to let your body heal. So at the moment no sugar/artificial sweetners, gluten, dairy, eggs, soy, corn or peanuts are allowed. I fill in a journal about what I have been eating and general symptoms to see if anything gets better over time when my body gets a chance to heal. So far it has gone great. It takes some extra planning since almost everything seems to have one or the other of these foods but I was quite use to it even before I became this strict with it.
I find that Black & White rules (Swedish) from Bevan James Eyles meaning a clear yes or no rule to steer your behaviour helps a lot. If you don’t have a set rule your brain tries to come up with excuses and exceptions to this rule. You need to decide firmly that it’s a Black & White rule there is no space for negotiations from your tired/hungry/craving brain. Back it up with all the great benefits that you will get if you do it properly and all the negative aspects of not changing your behaviour. Since I’ve set this up as a Black & White rule I don’t have to use willpower. I just have to plan and be prepared for all eventualities.