Five weeks for me. The first week was the easiest. Then I lost the ability to hold a conversation with people. Then I started to feel weak and tired. Then I started feeling good. Then the fourth/fifth week was the worst. I cramped up to the point my arms were curling in on themselves and I thought I would die. Potassium, magnesium and licking salt off my hand fixed that up and it's been smooth sailing ever since.
Female, 5'3", 49, Starting weight: 163lbs. Current weight: 135 (more or less).
Starting squat: 45lbs. Current squat: 162.5 x 2