Intermittent fasting gets most of the attention, but extended fasting — 24 hours or more — offers profound metabolic benefits that shorter fasting windows cannot replicate.
A 24-hour fast, done once or twice per week, dramatically increases autophagy (cellular self-cleaning), depletes liver glycogen completely, and deepens ketosis. Most people find a dinner-to-dinner fast easiest.
At 48 hours, human growth hormone peaks, autophagy reaches its highest rate, and the immune system begins regenerating stem cells. This can be done monthly for a powerful metabolic reset.
The 72-hour fast is advanced. It triggers the most significant immune regeneration and is used therapeutically in cancer support research. Requires medical supervision for those with health conditions.
Break gently with a small serving of easily digestible fat and protein — such as bone broth, then soft eggs or avocado. Avoid large meals immediately. Explore our keto beverages for excellent fast-breaking options and light keto snacks.
Extended fasting is not for beginners, but for experienced keto dieters it is a powerful tool. Start with 24 hours and progress slowly.