A study published in ‘Science Advances’ explains why some people cannot drink red wine, even in small quantities, because it gives them a headache.

A team from the University of California at Davis (USA) has identified the flavanol compound, quercetin, found naturally in red wines as the culprit behind this issue. Quercetin is known for its antioxidant properties and is consumed as a supplement. However, when metabolized with alcohol, it can cause problems.

When quercetin reaches the bloodstream, it converts into a different form called quercetin glucuronide and blocks the metabolism of alcohol. This buildup of acetaldehyde toxin causes redness, headache, and nausea.

Acetaldehyde is a toxin that can cause facial redness, headaches and nausea in high levels. The medicine disulfiram prescribed to alcoholics to prevent them from drinking causes these same symptoms because the medication also causes the toxin to build up in the body when normally an enzyme in the body would break it down. About 40% of East Asian population also have an enzyme that doesn’t work very well allowing acetaldehyde to build up in their system.

The researchers believe that susceptible people who consume wine with even modest amounts of quercetin develop headaches, particularly if they have a preexisting migraine or other primary headache condition. The next step is to test this theory scientifically in people who develop these headaches by conducting clinical trials with red wines containing a lot of quercetin and red wines with very little to no quercetin levels. It’s important to note that there are still many unknowns about this subject, such as why some people seem more susceptible than others and what role do enzymes play in this phenomenon?