For the first few days of Atkins Diet Induction phase, you will be withdrawing from sugar and caffeine addiction. It will take 3 to 7 days for the sugar and caffeine addiction to leave your system. During this time, you may find that withdrawal from sugar and caffeine food addiction causes you to have headaches, diarrhea, nausea, "brain fag", and muscle cramps. This is commonly referred to as "induction flu". These are temporary side effects of Atkins Diet Induction phase. Soon, you will experience more energy, better moods, and no hunger pangs.