Well, for me this is a real problem. I cheated one time after 3+ months, I ate some cake at a wedding and... got 400 grams! If you take into account that I lose about 200 grams a day... and that the cake wasn't so good...this wasn't worth it. But as others said this is a WOL so if you don't do it frequently you won't have a problem. Try also not to go from 20 to 40 or more if you want to cheat. Up your carbs as little as possible as this sudden carb intake may cause you gain weight.