“Every time I drink that particular producer’s Nebbiolo, I get a headache”
“Whenever I drink [a popular South African red] I have a migraine.”
These two comments did not come from casual wine drinkers; the two people who made them are internationally respected winemakers. Neither is about to restrict their consumption to whites or organic or zero-sulphur natural reds, as many a non-professional headache-sufferer has done, but both were serious about their experience with these specific wines.
While a growing number of wine people are increasingly exercised about the threat of WHO health warnings, remarkably little attention has been paid within the industry to the very real phenomenon of wine headaches.
According to a study published late last year, over a third (37%) of alcohol drinkers get ‘occasional’ headaches from wine, beer or spirits that affect them too quickly and after too little alcohol to be dismissed as hangovers. In particular, of those whose ‘primary headaches’ set in within three hours of drinking, 28% blamed a glass or two of red wine: twice as many as named spirits. The figure for white, sparkling and beer, by comparison was just 10%.
Historically, blame for the problem has been directed at SO2, which is generally considered guiltless, and histamines. However, the researchers behind the latest study suggest that the culprit might be a combination of a naturally occurring flavonol called quercetin with alcohol.
The liver makes the poison
Whatever one’s opinion of the WHO attitude to alcohol as a poison, there is no dispute that, when ethanol is delivered to the liver, a highly toxic product called acetaldehyde is created. The human body is programmed to protect itself from harm, so it converts the acetaldehyde to acetate, a harmless fatty acid that is also created when fibre is fermented by bacteria in the gut.
Responsibility for the conversion of the acetaldehyde is delegated to a set of enzymes collectively known as alcohol dehydrogenase (ADH) or aldehyde dehydrogenase (ALDH), and this is where everything gets complicated, because the specific enzymes you or I may have will depend on our genes.
It is widely known that approximately 30-50% of East Asians — principally Japanese, Koreans and Han Chinese — suffer the blushing, nausea and headaches resulting from having ALDH enzymes that are ‘dysfunctional’. Their blood levels of acetaldehyde after drinking are higher. Perhaps not coincidentally, they have a lower incidence of alcoholism.
But, just as there are people in those countries who can drink some Westerners under the table, there are variations in the effectiveness of the enzymes between individuals in any group, irrespective of ethnicity.
The bad compound
This brings us back to the new research and quercetin, a plant compound found in a wide range of foods ranging from dark berries to citrus fruits, parsley, olive oil, apples, grapes and wine. Until recently, it was seen as an effective antihistamine, which, if previous theories about RWH – red wine headaches – were correct, might have made it a useful preventative. However, if Professor Andrew Waterhouse and Dr. Apramita Devi, of UC Davis are correct, when combined with alcohol, quercetin creates a compound called quercetin glucuronide that can inhibit ALDH.
The UC Davis research has only been carried out in the laboratory and at quite high doses, so we will have to wait for the results of scheduled tests on headache-suffering human beings before we can declare quercetin guilty.
But, in any case, that will only be part of the story. We will still have to analyse the specific wines that gave my winemaking friends so much discomfort and those two individuals’ genetics that made them susceptible while others could enjoy the same reds with no ill effects.
All I know is that the study of wine and health is not nearly as simple as the binary ‘alcohol gives you cancer’ or ‘wine protects you from heart disease’ arguments that increasingly seem to be dividing the medical and wine communities. And that, for as long as small amounts of some red wines give my friends and seemingly a large number of other people unexplained headaches, I’m not going to join any anti-WHO marches.
