Ever noticed your face turning red after a drink or two? Experts say this common reaction, known as “alcohol flush,” affects nearly 540 million people worldwide — and it may signal more than just embarrassment.

Normally, your liver breaks alcohol down into a harmless substance called acetate. But for those with alcohol flush, this process happens much slower. The body struggles to clear acetaldehyde — a toxic byproduct of alcohol — which builds up in the blood. According to doctors, this buildup triggers a histamine response, dilating blood vessels and causing the skin to turn red, especially on the face and neck.

Dr. Richard Piper of Alcohol Change UK warns, “People with alcohol flush are at higher risk of alcohol’s harmful effects, both immediately and long-term.” These risks include higher blood pressure, heart disease, and even certain cancers.

Because alcohol flush is genetic, there’s no cure — but experts say reducing or avoiding alcohol is the best prevention. Even light drinkers benefit from taking breaks, such as during “Dry January.” Cutting back can improve sleep, boost mood, and give your skin a healthy glow — without the flush.