If you enjoy drinking red wine, you've likely experienced the headache that can come with it.

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It's often the result of drinking one glass too many — but some people experience these headaches from just one small glass, as quickly as 30 minutes after drinking it.

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Why does this happen?

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Well, researchers from the University of California, Davis, and the University of California, San Francisco, have found a compound that may be responsible.

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In their study, published in Scientific Reports, the researchers did tests on different compounds found in red wine.

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Red wine contains high levels of quercetin, a compound found in many fruits and vegetables, including grapes, dark berries and onions.

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Quercetin usually has many health benefits — it's an antioxidant and is believed to help with things like inflammation and blood pressure.

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However, when mixed with alcohol, the researchers found that it can block the alcohol-metabolizing enzyme ALDH2.

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In the body, alcohol is first broken down into a toxic compound called acetaldehyde. ALDH2 then breaks that down into something called acetate, which is then broken down into water and carbon dioxide.

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If the action of ALDH2 is blocked, acetaldehyde builds up, which has been found to cause headaches, nausea flushed cheeks and sweating.

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The researchers were able to show that quercetin blocks ALDH2 in the lab and now hope to test these results with a group of human volunteers.

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The research also suggests that not all red wine may have the same effect. Grapes make more quercetin when exposed to sunshine — so wines from sunnier places are more likely to give the drinker a headache.

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Study co-author Morris Levin also said that people who are more susceptible to headaches in general are more likely to be affected by red wine.

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So if you're one of those people, maybe reach for a glass of white wine instead!