Flour has a long shelf life but generally goes bad after 3–8 months. White flour may last longest due to its lower fat content, while whole-wheat and gluten-free varieties spoil sooner. ... Be sure to throw out your flour if it has any unpleasant odors, discoloration, or mold growth.

What happens if you use expired flour?

Eating expired flour generally doesn't have significant consequences. “Most of the time, nothing happens other than that your baked goods don't taste good,” Knauer says. ... “If rancid flour contains large amounts of mycotoxins, it can make you sick,” explains Knauer.

Is out of date flour bad?

When flour goes rancid, its molecular structure changes — which may produce harmful compounds. However, no recent studies have revealed any detrimental effects of eating rancid flour. Although cooked foods made with it may taste unpleasant, they're unlikely to harm your health if eaten in small amounts.