Opinion: Doctors should educate patients about ‘Asian glow’ and drinking risks

The author opens with a childhood memory: at age 8, watching Gong Gong's face turn bright red after a few sips of yellow wine; he enjoyed his drinks, but seemed to enjoy the author's laughter even more. More than a decade later, the author recognized the same alcohol flush reaction at parties and happy hours in some East Asian friends and in themselves. Some friends took histamine blockers such as Pepcid AC before going out to hide the anticipated redness, and the author once watched someone keep drinking through the flush to prove a higher tolerance than their body was signaling. Most knew the reaction by the colloquial name 'Asian glow,' which makes it sound harmless, even playful.

During medical school, at an Asian American and Pacific Islander Heritage Month event, the author learned the science after an ethanol patch test turned positive. Flushing is a common marker of reduced activity in mitochondrial aldehyde dehydrogenase 2, or ALDH2, an enzyme involved in breaking down alcohol. This inherited deficiency affects an estimated one-third of people of East Asian descent and is exceedingly rare in other ethnicities. The associated redness may be mistaken for rosacea—some studies suggest drinking can raise the risk of developing rosacea—but rosacea is a separate chronic inflammatory condition that affects all skin tones and types.

There is no safe or healthy level of alcohol consumption for any given person, the author writes, but people with ALDH2 deficiency face both immediate discomfort and long-term cell damage and susceptibility to cancers of the upper digestive tract. Every clinician with East Asian patients should dedicate time to explaining the biological consequence behind what has long been dismissed as an aesthetic quirk. When ALDH2 activity is reduced, acetaldehyde, a toxic intermediate in alcohol metabolism, accumulates; it dilates blood vessels, promotes histamine release, and causes facial redness, nausea, and rapid heartbeat. Acetaldehyde is also a DNA-damaging mutagen with implications in cell death pathways.

Not every person with the deficiency presents the same way. People heterozygous for the most common reduced-function mutation, ALDH2*2, inherit one active copy of the gene from one parent and one variant copy from the other. Their symptoms are not severe enough to discourage continued drinking, so they often keep going, even though their alcohol consumption is associated with a greater risk of cardiovascular disease, brain disorders, pancreatitis, and malignancies, particularly esophageal cancer. Homozygotes, who inherit two inactive copies of the gene, are less likely to develop cancer because they get such severe reactions to drinking that they avoid alcohol. The excerpt then begins a final point noting that although many East Asians recognize that they flush after drinking, the sentence is cut off.