On Atkins you really should eat every 5-6 hours. If not hungry then a small controlled carb snack. There are some people who do choose to do 1 day fasts, mostly for spiritual reasons. If you choose to do that I wouldn't recomend going over 1 day. Also NO JUICE. Juice is the fastest way for the gluclose to enter your system and your insulin will shoot up. Instead of doing a detox you may actuly do more harm. Juice is one of the very last things that are added back in on OWL or premaintanance.