Q. Dear Rabbi, many of us need a little coffee in the morning to have enough concentration on our tefillos. However, I'm finding recently that my stomach acids are creating a strong bad smell from my breath. I've tried extra brushing and mouthwash, but it's not from the mouth but the stomach. I'm concerned it may affect others around me as the smell certainly bothers my wife. While on weekdays it's a smaller issue.... but on Shabbes it's worse as we don't eat until nearly noon. Not sure if I should try to daven part of the tefillos and then say kiddush at home and eat something small before coming to shul? Any ideas/suggestions. Thank you.
A. Shulchan Oruch (O.H. 89: 3) rules that you may eat and drink for medical reasons before davening. Mishna Berura (ibid. 24) explains that the reasons for not eating mentioned in the Talmud (Berachot 10b) "You hast cast Me behind your pride" (Melachim I, 14:9) and the prohibition of; "You shall not eat on the blood" (Vaykra 19:26), meaning; "Do not eat before you have prayed for your blood" do not apply when eating for healing purposes. Mishna Berura and other Poskim are also more lenient once Krias Shema and the "Morning Brochos" have been recited. However, your situation may not necessary qualify as a medical condition.
Shmiras Shabbos Kehilchoso (2: 52: 29) quotes Rav Sh. Z. Auerbach Zt"l opinion that these two prohibitive reasons do not apply for amounts of food less than a "kezais" (approximately 28 grams), although some Poskim disagree (see Asia, Shvat 5765).
Horav Shlomo Miller's Shlit"a opinion is that it is better to avoid eating solid foods before praying when possible, and rather settle your stomach acidity with milk, tea or other non-acidic drinks.
(I consulted with an experienced and well-informed doctor, and he explained to me that the bad breath when fasting may be a symptom of Gastroparesis, or delayed gastric emptying or other conditions. This is worth checking.
Rabbi A. Bartfeld as advised by Horav Shlomo Miller Shlit"a