Researchers have finally figured out why red wine, despite being one of the most consumed alcoholic beverages, induces headaches for some, even if they are fine drinking other alcohol.
And there have been cases where some even experience flushes and feel nausea soon even after consuming in small amounts.
According to University of California researchers, who published their study in Scientific Reports, this happens because of a chemical compound present in red grapes that affects how the body metabolises alcohol in wine.
This compound is called quercetin, which is naturally found in fruits and vegetables, including grapes.
Occurs due to quercetin
“We think we are finally on the right track toward explaining this millennia-old mystery,” co-author Morris Levin, professor of neurology and director of the Headache Center at the University of California, San Francisco, said in a statement.
“Quercetin is produced by the grapes in response to sunlight,” wine chemist and co-author Andrew Waterhouse, professor emeritus with the UC Davis Department of Viticulture and Enology, said in a statement.
“If you grow grapes with the clusters exposed, such as they do in the Napa Valley for their cabernets, you get much higher levels of quercetin. In some cases, it can be four to five times higher.”
Quercetin is generally believed to be a healthy antioxidant and is sold as a supplement in the markets. However, when mixed with alcohol, it can produce certain reactions that our body can’t handle.
“When it gets in your bloodstream, your body converts it to a different form called quercetin glucuronide,” Waterhouse said. “In that form, it blocks the metabolism of alcohol.”
Millennia-old mystery solved
Generally, there is a two-step process for how the body metabolises alcohol. The first converts alcohol in the form of ethanol to acetaldehyde. The second turns acetaldehyde to acetate, which is used to produce energy, carbon dioxide and water.
However, in the presence of quercetin glucuronide, this second step is disrupted, resulting in a buildup of acetaldehyde.
“Acetaldehyde is a well-known toxin, irritant and inflammatory substance,” lead author Apramita Devi, a postdoctoral researcher with the UC Davis Department of Viticulture and Enology, said.
“Researchers know that high levels of acetaldehyde can cause facial flushing, headache and nausea.”
(With inputs from agencies)