Acid reflux while fasting

Why reflux can show up on a fast

Heartburn is a burning feeling in the chest from stomach acid travelling up toward the throat. The NHS page on heartburn and acid reflux says symptoms are often worse after eating, when lying down, and when bending over. If it keeps happening, that page calls it gastro-oesophageal reflux disease (GORD).

You can still have acid in the stomach when you have not eaten. Some people notice the burning then. Others notice it when they break the fast with a large meal. Both show up. The research is too thin to turn either pattern into a rule about fasting.

In 2023, Yan Jiang, Irene Sonu, and colleagues followed 25 people who were already being tested for reflux. They published the results in the Journal of Clinical Gastroenterology. For two days the people ate as usual. For the next two days they kept a 16-hour fast and an 8-hour eating window, during a 96-hour acid measurement. Nine of the 25 kept the full schedule. Average acid exposure time was 3.5 percent on the fasting days and 4.3 percent on the other days. The estimated change was a drop of 0.64 percentage points, but the range around it runs from a drop of 2.32 to a rise of 1.05. That range includes no change, so they call it weak evidence of a mild drop. Scores for heartburn and regurgitation were 14.3 on the usual days and 9.9 on the fasting days, and the range around that drop did not include zero. It is one short study, and most people in it did not keep the full fast. It does not settle the question for everyone else.

The NHS lists coffee, fatty food, and spicy food among the things that can cause heartburn or make it worse. People who fast also describe burning after strong tea on an empty stomach, after lying down soon after a drink or a meal, and after a large first meal eaten quickly.

Baking soda

Baking soda is sodium bicarbonate. MedlinePlus describes it as an antacid for heartburn and acid indigestion, and lists baking soda as another name for the same medicine. It neutralizes acid, which is why it is an old home remedy.

It is mostly sodium. A Church & Dwight Arm & Hammer baking soda label in the U.S. DailyMed listing, revised in January 2020, says each half teaspoon contains 616 milligrams of sodium. The same listing shows a marketing end date of 3 September 2020, so another box can print a different number. The sodium sits on top of any salt already in the water. Which salt for a water fast? is the note on that pinch.

A doctor sometimes prescribes sodium bicarbonate to make the blood or the urine less acidic. MedlinePlus says not to use it for longer than 2 weeks unless a doctor tells you to. The Arm & Hammer label says to stop and ask a doctor if symptoms last more than 2 weeks. Day-after-day use is a different act from a one-off. This library does not publish a dose.

Tell a doctor before using it if you have high blood pressure, congestive heart failure, or kidney disease. MedlinePlus also says the medicine adds sodium, so people on a sodium-restricted diet should check with a doctor first. The Arm & Hammer label says to ask a doctor before use on a sodium-restricted diet, and to ask a doctor or pharmacist before use with a prescription drug, because antacids can interact with some medicines. MedlinePlus says to separate sodium bicarbonate from other medicines by at least 2 hours.

What people usually change first

Skip coffee on an empty stomach, or drink it in the eating window. The NHS lists coffee among the drinks that can make heartburn worse. People who feel water come back up usually sip it, instead of drinking a large amount at once.

Stay upright after you drink or eat. The NHS says not to eat within 3 or 4 hours of bed. If nights are the problem, raise the head of the bed by about 10 to 20 cm, with wood, bricks, or books, so the chest and head sit above the waist. Extra pillows are a different setup. The NHS says they can press on the belly and make symptoms worse.

Break the fast with a small, plain meal. Fatty food and spicy food are on the NHS list of things that can make heartburn worse. Breaking a fast gently is the note for that first meal. A pharmacist or a doctor can suggest a reflux treatment and check it against your other medicines.

When it is not just reflux

See a doctor if the burning shows up on most fasts, or if it keeps coming back. The NHS says to see a GP when heartburn happens most days, when simpler changes and pharmacy medicines are not helping, or when food gets stuck, you are often sick, or you lose weight for no reason.

Get help promptly for trouble or pain when you swallow, for vomit that is blood or looks like coffee grounds, for black stools, and for weight loss you cannot explain. The NHS page on vomiting blood says vomit can look like coffee granules, and that black stools along with vomiting blood need emergency help. MedlinePlus lists vomit that resembles coffee grounds, and bloody, black, or tarry stools, as reasons to stop sodium bicarbonate and call a doctor.

Chest pain can be the heart. The NHS page on heart attack says the pain can feel crushing or squeezing, can feel like indigestion, and can spread to the arm, the neck, or the jaw. Shortness of breath and sweating are on that list too. If the pain is new or severe, if it spreads to the arm, neck, or jaw, or if it comes with breathlessness or sweating, treat it as an emergency.

Stop the fast for chest pain, and get help. The signs for stopping are in When to stop a fast. Heart disease, kidney disease, and the medicines that change whether a fast is safe are in Who should be careful with fasting.