A small glass of red wine may not be harmful, but while this may hold true for some adults, a few individuals experience severe headaches even with a few sips. Red wine is considered a trigger for migraine attacks, although this association is not entirely undisputed. Histamine intolerance may play a role, but the research is still puzzling over the exact mechanisms that cause the symptoms in the body.
Recently, a group of substances called polyphenols, specifically the flavonol quercetin, has come under scrutiny as a potential trigger for headaches. Quercetin appears to interfere with the metabolism of alcohol in some individuals, according to findings from the University of California, Davis.
This wine component is naturally present in almost all fruits and vegetables in varying concentrations, with higher amounts found in red wine compared to white wine. Despite being recognized as a healthy antioxidant and even included in dietary supplements, when quercetin interacts with alcohol, it can lead to issues, as observed by the researchers.
Quercetin and Alcohol Metabolism
“When it enters the bloodstream, the body converts it into quercetin glucuronide,” explained Andrew Waterhouse, senior author of the study published in the journal Scientific Reports. “In that form, it blocks the metabolism of alcohol.” The conversion process stutters, leading to a buildup of acetaldehyde. This intermediate in alcohol breakdown significantly contributes to the morning-after “hangover,” causing notable symptoms such as facial flushing, headaches, and nausea.
“Acetaldehyde is a well-known toxin, irritant and inflammatory substance,” noted Apramita Devi, the lead author of the study from UC Davis. A medication named Disulfiram operates on a similar principle to quercetin, blocking alcohol metabolism to deter alcoholics from drinking. Acetaldehyde accumulates, resulting in unpleasant hangover symptoms without the preceding intoxication.
Beneficial Without Alcohol
The researchers hypothesize based on genetic variations in these interactions. About 40% of people of East Asian descent possess a genetic variant causing metabolism issues when consuming alcohol. In these individuals, acetaldehyde accumulates, leading to headaches, facial flushing, and nausea. Laboratory investigations revealed that quercetin indeed has a comparable effect on alcohol metabolism. When exposed to sunlight, grapes produce the substance, which Waterhouse described as acting as a “sunscreen” for grapes.
While quercetin in combination with alcohol may induce headaches, it alleviates them when consumed without wine. Anecdotal reports of its effects have been supported by studies with laboratory rats, demonstrating that increased quercetin intake can reduce or even prevent migraine pain. The researchers suspect this is due to the antioxidative and anti-inflammatory potential of quercetin.
Mitigating the Consequences
However, robust confirmation that quercetin is responsible for red wine-induced headaches still awaits validation. Not all experts in the field are convinced. Vasilis Vasiliou, an alcohol metabolism specialist at Yale University, raises concerns in the New York Times, pointing out that what happens in a petri dish may not necessarily occur the same way in our bodies. Some studies even suggested that quercetin could protect against alcohol-related damage, such as liver issues.
Devi’s team acknowledges that detailed studies are still pending. Their next step involves initiating clinical tests where participants will consume wines with varying quercetin doses. “Researchers said there are still many unknowns about the causes of red wine headaches. It’s unclear why some people seem more susceptible to them than others,” concluded the scientists.