By Christophe Lavelle - Researcher in molecular biophysics, epigenetics and nutrition, CNRS UMR 7196, Inserm U1154, National Museum of Natural History (MNHN)
When your head reminds you of the excesses of the previous night... Does the quality of the drink have an impact on the pain? Are there any scientifically approved remedies? Can a hangover be prevented?
Illustration image Pixabay
Since when have we had a
hangover (or "veisalgia" for scientists)? Probably for much longer than wine and other fermented beverages have been invented. Indeed, 10 million years ago, our ancestors could have consumed fallen fruits, potentially rotten and therefore loaded with alcohol. However, while this consumption has an advantage due to the calorie richness of ethanol, with its 7kcal/g compared to only 4 for carbohydrates or proteins, it does not come without a downside that our predecessors probably quickly realized: alcohol first makes you cheerful... then sick.
Indeed, our body is not well adapted for this consumption, and alcohol remains toxic, even though evolution has done what it could by stabilizing a mutation in our genome in the gene coding for
the enzyme ADH4 (alcohol dehydrogenase 4), making it 40 times more efficient in performing the first step of alcohol detoxification.
This mutation does not, however, immunize us against the effects of alcohol.
As soon as it is swallowed, alcohol quickly passes through the stomach to reach the intestine, then the bloodstream (it is detected in the blood a few minutes after ingestion), irrigating all our organs, including the brain (the first effects are then felt) and the liver (the second effects arrive), quite dramatically if the ingested doses are extreme: the body then signals poisoning with nausea, vomiting... or even an alcoholic coma (and death) in the most severe cases.
But let's return to the fortunately more common case of a "moderate excess." In the brain, first, alcohol will have different roles, including boosting the secretion of dopamine (hence the rather stimulating and euphoric effect at first), before the sedative effect takes over and leads to the characteristic drowsiness phase. We then fall into a rather restless sleep... and the awakening painfully reminds us of the excesses of the previous night, and
the more or less severe intoxication that results.
Because it is the liver that is responsible for breaking down alcohol, transforming ethanol into acetaldehyde and then into acetate, these two compounds unfortunately still being toxic to our body. However, alcohol also disrupts the production of vasopressin, an antidiuretic hormone that regulates kidney activity, which is rather a good thing, as it is necessary to urinate to eliminate all these toxins: the body then uses water, a lot of water to eliminate alcohol... resulting in dehydration which is one of the causes of migraines.
Add to this the vasodilatory effect of alcohol (with that little feeling of "heat rush" after the first sips, which is a real trap, because, once the misleading sensation has passed, the body cools down even faster), as well as the disruption of blood sugar, the secretion of neurotransmitters and the triggering of an inflammatory response,
all effects that contribute to headaches, without the mechanisms always being very clear.
On this subject, down with legends: yes, even very good wines give you a hangover. Yes, even "natural" wines. Because no, sulfur is not responsible, but indeed alcohol. Or only in some people particularly sensitive to sulfites; but others will be more sensitive to histamines and other biogenic amines,
which some low-sulfite wines contain in larger quantities...
Finally, in case of unavoidable excess, are there any relief strategies? Foods that can help? Medications? Only fasting seems recommended (to lighten the liver) and rehydration with your best winter herbal teas,
even if it won't work miracles on your headache.
As for the over-the-counter market, it may be flooded with "anti-hangover" formulas (based on vitamins supposed to boost liver activity or probiotics supposed to "capture" alcohol before it enters the bloodstream), no reputable scientific study has been able to prove the effectiveness of these pills. There is little left but paracetamol or ibuprofen to relieve the pain.
However, beware of the hepatotoxic effects of these molecules: it is not about finishing off your liver. And above all, also avoid the temptation to treat the problem with the problem by having another drink, because while the anesthetic and analgesic effect may give the impression of temporarily relieving your cranial pain, it will only make it come back stronger later!