Most mainstream halachic opinions hold that you should not chew gum on Yom Kippur, even if you don’t swallow it and even if it is flavorless.

Core halachic idea

  • Yom Kippur includes a Torah-level prohibition on eating and drinking, and rabbinic law adds that even “tasting and spitting out” is not allowed on this day.
  • Chewing gum is treated by many rabbis as a form of “eating,” since you enjoy flavor and extract substance from it, and would normally require a berachah when chewed on a regular day.

Gum on Yom Kippur

  • Several halachic Q&A responsa state clearly: “No, it is not permitted to chew gum on Yom Kippur,” comparing it to tasting and expelling food.
  • Some modern guides mention a limited leniency for completely flavorless gum for those who truly struggle to fast, but they immediately add that it is proper to be strict and avoid it.

Why it’s discouraged

  • Even when flavor is gone, the act of chewing closely resembles eating, which goes against the spirit of the fast and the focus on spiritual reflection.
  • There is also a concern of mar’it ayin (appearance): other people may think you are eating on Yom Kippur if they see you chewing.

What if you already did?

  • Many rabbinic answers stress that someone who chewed gum by mistake should not panic, but should stop immediately and continue fasting.
  • For personal guidance (especially if you have medical or anxiety issues), a competent rabbi who knows your situation should be consulted before the fast.

In practice: if you are healthy and asking, “Can you chew gum on Yom Kippur?”, the recommended answer from contemporary halachic sources is no, you should avoid chewing gum at all.

Information gathered from public forums or data available on the internet and portrayed here.