Eating expired bread is generally harmful, food poisoning and other hazards may occur, while the nutritional value is reduced. If the expiration date of the bread stale, the surface of the mold and odor, after eating may cause poisoning, mild nausea, vomiting, fatigue, diarrhea and other symptoms; serious may also cause dizziness, headache, severe vomiting, blurred vision, pupil dilatation, dyspnea, blood pressure and pulse changes and other phenomena, need to pay attention to. If necessary, you should seek medical attention in a timely manner, under the guidance of the doctor for gastric lavage, rehydration and other treatments. A lot of nutrients in expired bread will be reduced accordingly, resulting in the loss of nutrition and little food value. It is recommended that you do not consume expired bread in your daily life, and if you have already consumed it, you should go to the hospital immediately for diagnosis and treatment if you experience any discomfort, to avoid delaying the treatment and causing adverse consequences. If you eat a lot of moldy expired bread for a long time, it may also increase the risk of cancer.