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Medical considerations for red wine headaches back to Roman timesbut the experience is probably as old as winemaking – Something like 10,000 years. As a chemistspecialized in winemakingWe wanted to try to figure out the origin of these headaches.
Many components of red wine have been accused of causing this misery. sulfites, biogenic amines and tannin are the most popular. Our research suggests that the likely culprit is something you didn’t consider.
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The usual suspects
Ever since labeling became mandatory on US wines in the 1990s, sulfites have been a popular scapegoat for all kinds of ailments. However, there is not much evidence directly linking sulfites to headaches, and other foods have comparable levels of wine without the same effect. White wines also have it the same amount of sulfites as red wine.
Your body produces about 700 milligrams of sulfites every day metabolize protein in your food and excreted as sulfate. For this purpose, it contains compounds called sulfite oxidase that produce sulfate from sulfite; the 20 milligrams in a glass of wine are unlikely to overwhelm sulfite oxidases.
Some point the finger at biogenic amines for red wine headaches. They are nitrogenous substances found in many fermented or spoiled foods, and they can cause headaches, however quantity in wine is too low to be a problem.
Tannin is a good guessbecause white wines have only small quantities, and red wines have large quantities. Tannin is a type of phenolic compound – found in all plants and usually prevents disease, repels predators or promotes animal seed dispersal.
But there are many others phenolic compoundsin grape skin and seeds in addition to the tannins that turn into red wine from the winemaking process, which are not present in white, so any of these could be a candidate for the culprit.
Tannin is also found in many other common foods, such as tea and chocolate, and generally does not cause headaches. And phenolics are good antioxidants– they are unlikely to cause inflammation that would cause a headache.
A red wine
Some people get red skin when they drink alcohol, and it’s red accompanied by a headache. This headache is caused by a delayed metabolic step, when the body breaks down alcohol.
Alcohol metabolism occurs in two steps. First, ethanol is converted to acetaldehyde. The ALDH enzyme then converts acetaldehyde into acetate, a common and harmless substance. This second step is slower for people with red skin because their ALDH is not very effective. They accumulate acetaldehydethis is a somewhat toxic compound also hangover related.
So if something special about red wine inhibited ALDH, slowing down this second metabolic step, would that lead to higher acetaldehyde levels and headaches? To try to answer this question, we analyzed the list of phenolics that are abundant in red wine.
We saw a paper showing that quercetin is a good inhibitor of ALDH. Quercetin is therefore a phenolic compound found in the skin of grapes it is much more abundant than in red wines, because the skins of red grapes remain in the fermentation process longer than the skins of white grapes.
Enzyme testing
Testing for ALDH was the next step. We set up an inhibition assay in test tubes. In the experiment, we measured how the ALDH enzyme decomposes acetaldehyde. We then added the suspected inhibitors – quercetin, as well as some other phenolics we wanted to test – to see if they slowed down the process.
These tests have confirmed it that quercetin was a good inhibitor. Other phenolics had different effects, but quercetin glucuronide was the winner. When your body absorbs quercetin from food or wine, it’s most of it is converted to glucuronide to remove the liver from the body quickly.
Our enzyme tests suggest that quercetin glucuronide disrupts your body’s metabolism of alcohol. This disruption means extra acetaldehyde circulates, causing inflammation and headaches. This finding represents what is known as a secondary or synergistic effect.
These side effects are much more difficult to identify, as both factors must be in play for the result to occur. In this case, other foods containing quercetin are not associated with headaches, so quercetin may not be the cause of the red wine problem at first.
The next step might be to give human subjects two red wines that are low and high in quercetin and ask whether either wine causes headaches. If wine high in quercetin causes more headaches, we know we’re on the right track.
So if quercetin causes headaches, are there red wines without it? Unfortunately, data on specific wines is too limited to provide helpful advice. However, grapes exposed to the sun produce more quercetin, and a lot of it cheap red wines they are made with grapes that see less sunlight.
If you’re willing to take a chance, look for a cheaper, lighter red wine.
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