The re-feeding period after water-only fasting is essential to ease the person back into normal eating, optimize the benefits of the fast, and reinforce the success of the fasting experience. In fasting centers, the typical standard of care is to utilize half the time of the fast to ease back into a full eating regimen. So if you fast 7 days, you should take another 3-4 days to break the fast. If you fast two weeks, you should take another week to break the fast. A conservative approach to the introduction of food and activity is in the best interest of all fasters at any age.

This is especially important following extensive periods of fasting to avoid a potential devastating metabolic condition called re-feeding syndrome. This can occur when an abrupt, rapid and excessive intake of carbohydrates, like that found in whole fruits and vegetables,  causes a sudden and rapid shift from the fat-burning metabolism of fasting to the glucose-dependent growth of cells (anabolism). A rapid elevation of glucose can cause a surge in insulin, and a voracious demand of electrolytes by growing/rebuilding cells that results in potentially dangerous deficiencies of electrolytes (phosphorous, magnesium and potassium) in the blood. This can result in an array of diverse symptoms including nausea, vomiting, low blood pressure, weakness, seizures and heart arrythmia. 

This is another reason why fasting with proper professional monitoring by physicians sanctioned by the IAHP,  and associated with the NHA, is so important. If there are two mistakes that are commonly made after fasting, they are eating too much too soon, and moving too much too soon. Food needs to be gradually introduced after a period of water only fasting. Fasts are most successfully broken with a succession of nutrient dense foods including diluted and full strength greens-based vegetable juices, vegetable broth/soups, melons and other fresh fruit, fresh raw vegetables and salads, and eventually cooked vegetables/starches  (potatoes, legumes and whole grains). The sequence and quantity of these food items should be carefully monitored, and adjusted to the needs, responses and conditions of the faster.  

Just remember that because of the elimination of all calories, a natural starvation response  may be enhanced after periods of severe calorie restriction that can promote significant reactive weight gain after a fast if healthy, low calorie dense, low sodium, plant-based eating and lifestyle habits are not maintained. All processed, ultra-processed and animal based foods should be avoided. There is a kind of ledger sheet, an internal recognition system that the body uses to match its calorie intake to its calorie output. If you’re restricting your intake of calories but burning a lot of calories in physical movement, the body will slow down resting metabolism to hold on to future calories more forcefully, and you can begin to gain weight on less and less food intake. 

Since there are no calories coming in during a fast, increasing physical activity during a fast should be avoided. It can promote excessive reactive weight gain after the fast, and also promote negative reactive changes in blood sugar and blood pressure during the fast. Therefore, maintaining as much rest as possible is recommended during the fast, followed by moderate activity, and a whole food plant-exclusive diet without added oil, refined sugar, animal products, and salt. 

Physical activity should also be gradually introduced after a fast. If you have been doing nothing but resting during an extensive fasting period, it is in your best interest to ease back gently into an ongoing exercise regimen. Doing too much too soon can cause undue physiological stress to the body, extend weakness and frailty, and delay recovery time. Depending on the length of the fast, I typically recommend short periods of walking, swimming, or biking on a stationary bike, or even rebounding on a rebounder, just about 4-5 minutes at a time a few times a day, for the first few days after fasting. After this period, activity can be extended several minutes a day over time until you’ve built up to about 30-45 minutes a day.

Breaking the fast with proper supervision is essential to an optimal fasting experience. Being conservative in your eating and exercise choices after water only fasting will enhance any of the benefits you have achieved during the fasting process.