Survive the Fast – A Practical Guide


tisha-bav1. Before the Fast – Hydrate

a. The #1 best preparation for fasting is adequate hydration. Drink the equivalent of 8-10 cups of water in the course of a day (about 4 or 5 water bottles) for at least 3 days before the fast. Electrolyte replacements like PowerAde or Gatorade are useful after strenuous exercise but are no substitute for regular and adequate hydration.

b.      Avoid drinks or foods that cause your body to get rid of water on the day before the fast. Such foods and drinks include alcohol, tea, caffeinated coffee and chocolate. Avoid processed foods containing lots of salt such as pickles, cold cuts, or cheese. Most tomato sauces, canned fish and smoked fish have a lot of added salt.

c.       The above is a good rule-of-thumb for hot, humid days in general.

2.      Erev Ta’anis

a.      Eat a good breakfast. It will help stretch your stomach and give you energy throughout the day.

b.      Eat a light lunch and avoid eating between lunch and the pre-fast meal. Avoid starting the pre-fast meal on a full stomach.

c. Don’t get a headache: Withdrawing from caffeine produces a headache in people who drink several cups of coffee a day. If you consume this much caffeine in coffee or other foods or drinks you should prepare yourself for the caffeine-free period by reducing or eliminating caffeine from your diet in the days before the fast. Don’t try to get through the fast by drinking coffee right before the onset of the fast, since this will cause you to lose a lot of water.

d.      The Pre-Fast Meal:

i.      Drink at least 2 cups of water to help digestion.

ii.      Include some foods high in oils and fats in the pre-fast meal, since such foods delay emptying of the stomach and effectively prolong your meal.

iii.      Beware of fatty meats or salted potato chips that could load you up with too much salt.

iv.      Salads and other high fiber foods that are so important in one’s normal diet should be de-emphasized for the pre-fast meal since they travel quickly through the digestive system.

v.      Fruit, despite its high fiber content, is worthwhile since it carries a lot of water in a “time-release” form.

vi. Make the meal tasty enough so people will eat: The pre-fast meal doesn’t have to be bland. Spices such as lemon or herbs are fine for fasting, but salt and monosodium glutamate should be reduced as much as possible.

3. The Fast

a. Do Not Stop taking Medications without consulting your physician.

b.      Any medications taken on a fast day must be taken with enough water to clear the esophagus. Serious injury and infection can be caused. This is not considered drinking and breaking the fast.

c.       Anyone with a medical condition or recent infection or illness MUST CONSULT WITH A PHYSICIAN AND ROV first, before undertaking the fast. Avoid waiting to the last minute to ask a Shailah.

d.      Children under Bar-Mitzvah or Bas-Mitzvah have absolutely no obligation, Mitzvah or benefit from fasting any of the Ta’aneisim besides Yom Kippur. There is no Chinuch or training for fasting.

e.      The Halacha clearly states that boys 12 years old and girls 11 years old should try to fast as much as they can on Yom Kippur. But they must avoid becoming weakened or ill. At the age of 11 and 10 respectively, they should fast till an hour or two past their usual breakfast time AND THAT’S IT. Any children below that age should not fast at all. If they are up to it, they may withhold food and drink on the night of Yom Kippur since they ate earlier.

f.        DO NOT ASSUME that it’s okay to continue fasting if you are not feeling well. Speak to a doctor. Ask a Rov.

4. After The Fast

a. Don’t eat improperly after Fasting: Even people who have prepared well for fasting will be hungry after Maariv.

b. Be sure not to eat food too quickly at the post-fast meal.

c. Begin the break-fast meal with several glasses of milk or juice: these put sugar into the bloodstream and occupy space in the stomach, discouraging you from eating too rapidly.

d. Be careful about eating high salt foods such as lox, since you will still be a little dehydrated.

e. Don’t try to make up for fasting by stuffing yourself. Keep it light and simple.

f. Drink a lot of fluids to avoid waking up extremely thirsty in the early morning hours.

Adapted from an article by Michael M. Segal MD PhD

Prepared by Rabbi Yisroel Kleinman, Former Oorah Camp Director

{ Newscenter}


  1. Wow! I am so happy this doctor and Rabbi Kleinman are bringing us this article about “surviving” the fast. Mommish till now there were people dropping like flies R”L. Without this knowledge about drinking lots of water “it should clear the esophagus”, there were mommish multitudes that had this problem. Yidden always fasted and B”H nothing happened. Everyone used common sense.
    Dear yidden, why do we need these scare tactics and made up problems? Don’t we have enough without these people? Maybe they should set up an organization for this cause?

  2. Thank you. There is a lot of great advice. You should of published this a few days ago so we could of prepared ourselves better (like drinking a lot of water 3 days in advance). Let’s hope everyone has an easy fast.

  3. Excellent general advice but if you are at risk for hyponatremia or have potassium disorders ask your doctor and he will advise adjustments. Remember, electrolytes imbalance is very dangerous and quickly so, and it may not be obviously evident.

    As for children, ask your Rav, I don’t think everyone holds like Dr Segal.


Please enter your comment!
Please enter your name here