ד״ר זיו אב - איך לשבור צום

Short Summary

Main recommendation: break a short fast (water fasting up to about three days, or a 4–5 day "Salem" fast-mimicking diet) gently, starting with a small, easy-to-digest meal rather than a heavy or sugary one, while continuing electrolytes. Dr. Ziv Av notes that after several days of fasting the digestive system is sluggish, so overeating or eating heavy food can cause gas, pain, or diarrhea. Refeeding syndrome is more relevant to longer fasts, but he says similar effects can occur with shorter ones.

Key Points

• Break longer fasts more gradually, since the digestive system needs time to "wake up" after several days without food.
• Avoid sugary foods, carbohydrates such as flour products, and sweeteners (including artificial ones), which spike insulin and raise appetite.
• Use the post-fast period to keep avoiding sweets for a few more days, so the craving for sweetness fades.
• Electrolyte drinks help because fasting increases urinary loss of electrolytes; continue them on the day of breaking the fast, ideally before eating.
• Insulin spikes after eating drive electrolytes into cells, which is why sugary or carb-heavy meals raise the risk of dangerous electrolyte drops.

Details Worth Noting

• Concrete instructions:
  • Optionally eat a small "mini-meal" about 30 minutes before the main meal, such as some cooked vegetables, to gently wake up the digestive system.
  • Drink an electrolyte beverage before starting to eat.
  • Choose clean, non-heavy foods, for example avocado, olives, healthy fats, and fiber, and avoid carbohydrates and sweeteners.
  • Examples he gives of suitable foods: a small amount of olive oil, or a small portion of salmon — and he notes that for someone who no longer cares about preserving autophagy, this is also fine.
  • If you have high blood pressure or take diuretic medications (or any medication that increases electrolyte excretion), keep taking electrolytes on the day you break the fast.
  • Test on yourself whether eggs and dairy upset your stomach after a fast; if you want to be cautious, avoid them that day.
• Dr. Ziv Av says refeeding syndrome is mainly a concern after fasts longer than about a week, but people sometimes experience similar symptoms after shorter fasts.
• Bone broth is nutritious and supports gut lining recovery, but it contains more protein, so it may not suit someone who wants to minimize protein on the day of breaking the fast.
• He frames these as personal observations, and the video does not present them as professional medical advice.

Bottom Line

Breaking a fast is mainly about pacing and food choice: start light, keep electrolytes going, and avoid sugar and heavy carbs so the body can transition without digestive discomfort or electrolyte imbalance.