I have used Mega Hoodia for years. I use it to fast for roughly 36 hours at a time, from dinner 6-7pm the day before all the way until 6 am the day after. I take 3 pills at a time, hourly or as needed to fight appetite pangs. I normally fast one day a week to maintain my weight and 2 days a week, not consecutive, if I am dieting. Before Hoodia, if I fasted i would inevitably get stomach cramps. Not so, with the use of this product.