Headache after drinking wine. What is the cause?

Headaches are common, and headaches after drinking alcohol are particularly common. An interesting epidemiologic phenomenon, not yet adequately explained, is why red wine is associated with more headache than other forms of alcohol. There have been many studies fingering many suspects, from sulfites to tannins to various phenolic compounds, but none have really provided a concrete explanation for what might be going on.

A new hypothesis came to the fore this week in the journal Scientific Reports:

Alcohol is metabolized by the enzyme alcohol dehydrogenase in the gut and then in the liver. That turns it into acetaldehyde, a toxic metabolite. In most of us, aldehyde dehydrogenase (ALDH) quickly metabolizes acetaldehyde to the inert acetate, which can be safely excreted.

Some populations, particularly those with East Asian ancestry, have a mutation in the ALDH gene which can lead to accumulation of toxic acetaldehyde with alcohol consumption — leading to facial flushing, nausea, and headache.

The researchers focused in on the aldehyde dehydrogenase enzyme and conducted a screening study. Are there any compounds in red wine that naturally inhibit ALDH?

The results pointed squarely at quercetin, and particularly its metabolite quercetin glucuronide, which, at 20 micromolar concentrations, inhibited about 80% of ALDH activity.

Source: Medscape