If you’re on GLP-1 drugs and plan to fast for Yom Kippur, here’s what you need to know
Most people on GLP-1 drugs can safely fast for Yom Kippur or other religious observances, but they may need to plan ahead, take certain precautions or be ready to call it quits if they feel ill.
Millions of individuals in the United States, as many as one in eight adults, are currently taking GLP-1 medications like Ozempic, Mounjaro, Wegovy, and Zepbound to manage diabetes or aid in weight loss. The upcoming Jewish holiday of Yom Kippur, observed from sundown on September 20, 2026, until nightfall on September 21, 2026, adds a medical complication for those adhering to this fast.
Traditionally, Yom Kippur involves abstaining from both food and water for approximately 25 hours, significantly impacting a person's metabolism. Interestingly, various religious practices incorporate fasting, such as Muslims during Ramadan, who break their fast each night, and Christians and Hindus engaging in partial or dry fasts, like during Lent and Navratri.
As an obesity medicine specialist, I frequently interact with patients taking GLP-1 drugs and must provide them with essential guidance on fasting during religious observances. Most individuals can safely fast for Yom Kippur or other religious or cultural practices. However, depending on their circumstances, they may need to prepare ahead, take precautions, and be aware of situations where their doctor advises breaking their fast.
GLP-1 drugs, which include Ozempic, Mounjaro, Wegovy, and Zepbound, mimic a natural hormone called glucagon-like peptide 1. This hormone lowers blood sugar by triggering insulin release when levels are high and slows down stomach emptying, reducing appetite and promoting weight loss. Side effects of GLP-1 drugs can include nausea, vomiting, dizziness, constipation, and dehydration, which may worsen during fasting, especially for those susceptible to gastrointestinal discomfort.
To avoid exacerbating these side effects, it's advisable for patients to avoid starting a new GLP-1 medication or increasing their dose within two weeks or less before Yom Kippur. For those on a weekly injection schedule, it's crucial to adhere to the established routine, even during fasting. Weekly doses remain active throughout the week, so administering them as scheduled is generally safe, except on the day of fasting if it causes significant discomfort.
Patients using daily GLP-1 injections may need to adjust their timing. If a diabetic patient takes GLP-1 medication, it's essential to consider fasting's impact on blood sugar levels. Combining GLP-1 drugs with other diabetes treatments, such as insulin or sulfonylureas, increases the risk of hypoglycemia during a prolonged fast. Diabetic patients must consult their healthcare providers to adjust insulin doses, insulin type, and GLP-1 medication timing to ensure safe fasting practices.
For patients managing diabetes with GLP-1 medications, not overeating and staying well-hydrated before fasting are crucial precautions. Fasting can pose serious risks, particularly for diabetics taking these drugs alongside blood sugar-lowering medications, due to the heightened risk of blood sugar crashes. In such cases, adjusting medication timing, dosing, and insulin type is vital for safe fasting.
People with Type 1 diabetes, poorly controlled diabetes, frequent or severe blood sugar drops, hypoglycemia unawareness, severe kidney disease, or intolerable GLP-1 side effects should avoid fasting altogether.
Written by urgent.news from The Conversation's reporting — not their text. Machine-written — may contain errors; check the original before relying on it.
