The hardest part for me is definitely the first couple days. It's not so much that I'll buckle and cheat, because I'm pretty good at sticking with it, but my body has trouble adjusting to the much smaller portion sizes and I feel hungry almost all the time.
Of course, that's the fault of me being a glutton when I'm off a diet. I eat massive meals and my stomach gets stretched, so when I reduce my intake to an appropriate level I'm left hollow until my stomach can shrink to a healthy size.
Where I risk falling off a diet is when I visit home. I've lived on my own for the last five years, but when I spend a week or two at my parents' place for Christmas or a summer vacation I'm just surrounded by food that I'm better able to avoid at my own house. They've got two fridges, two freezers, and two pantries overflowing with delicious food.
I could go in the fridge to get some mustard to put on a low fat wrap and emerge with cheese and salami. Then I could go to the pantry to choose a can of soup and see my favourite flavour of chips and think, "One or two while my soup is heating up won't hurt." Except one or two becomes half the bag... or more. My parents' house is where diets go to die.
