Dizzy & Sick From Fasting

September 9, 2018

3 min read


It’s almost impossible for me to survive fast days. I get dizzy, sweaty, and nauseous to the point of throwing up. And I’m sick for two days after. I certainly wouldn’t be able to go to synagogue this Yom Kippur if I have to fast. What is my obligation for this fast day and for other fast days?

The Aish Rabbi Replies

I’m sorry to hear of your difficulties. On the minor fast days (all the others except Tisha B’Av and Yom Kippur), you should try to fast, but once you do not feel well you can eat as regular. The same is true of Tisha B’Av when it actually falls out on Shabbat but is pushed off until Sunday. (Note that this does not pertain to feeling weak and drained from the fast as most people do (or suffering a minor caffeine headache), but to actually feeling sick.)

Of course, in cases where you are permitted to eat, you should not pamper yourself. Only eat simple foods, and as needed to maintain your health.

Tisha B’Av and Yom Kippur are more stringent, and you should make a greater effort to fast for the entire day. In fact, it is better to rest in bed the entire Yom Kippur and not attend synagogue than to go out and make yourself sick so that you will have to eat. Fasting is practically the most important obligation of Yom Kippur – certainly more than hearing the inspiring High Holiday services.

If even with bedrest you begin to feel dizziness and signs of dehydration – or if you are certain they will begin, such as during very hot weather, then you may drink (and eat if necessary) in very small amounts at a time. Small amounts do not contradict the Torah’s obligation to “afflict” ourselves on Yom Kippur (Leviticus 16:31). Even after them, we are still so hungry and thirsty that we are “afflicted” by the fast. Thus, in cases of great necessity, this may be done to avoid having to actually eat and drink on these days.

See this related response about the amounts one may eat in such cases, and the intervals he must wait in between.

If even this is not sufficient and you are beginning to feel real dehydration, you may eat and drink as regular on Tisha B’Av and Yom Kippur. Note that on Tisha B’Av a person who is sick, even without a life-threatening illness, may eat as regular.

Although we have just presented the general rules, it’s important to discuss the particulars of each situation in person with a competent Orthodox rabbi. Every person and every situation is different.

We wish you an easy fast and a meaningful Yom Kippur. May you and yours be inscribed in the Book of Life!

(Sources: Shulchan Aruch O.C. 550:1, 686:2, Mishna Berurah 554:14, Biur Halacha 559 s.v. “v’aino”, 618, s.v. "choleh." Igrot Moshe O.C. III 91, Biur Halacha 554, s.v. “d'b'makom”, "Ohr L'Tziyon" III 29:10, Shemirat Shabbat K’Hilchatah I 39:18, Shiurin Shel Torah – Shiurei HaMitzvot 24,29, Middos V'Shiurei Torah (R. Ch. Benish) 15:10.)

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