by HARVEY FINKEL, MD
We are now greeted by a new report of a cure for hangover. We get one of these about once a year. This one, from the University of Helsinki and the University of Eastern Finland by Eriksson, et al., was published in the journal Alcohol and Alcoholism on August 18, 2O2O, and has stimulated many stories in the international press.
A double-blind study was performed on 19 healthy male volunteers (they answered advertisements), who drank 1.5 grams of alcohol per kilogram of body weight over three hours, about equivalent to a liter of wine, then ingested L-cysteine or a placebo. After a dose of 12OO milligrams, the L-cysteine group was observed to suffer reduced hangovers or even none at all, as compared to the placebo group. The authors also reported that a dose of 6OO milligrams of L-cysteine reduced post-drinking anxiety. Neither alcohol concentration, nor acetaldehyde concentration differed between the L-cysteine-treated subjects and those who received placebo.
L-cysteine is a non-essential amino acid, which is important in a number of metabolic roles. It is thought to neutralize acetaldehyde, a toxic product of alcohol that may be involved in the genesis of a hangover. It is sold in pills containing other vitamin supplements. One should be warned that, unfortunately, “health supplements” are generally not subject to FDA controls.
For several reasons, such reports must be viewed with watch-and–wait skepticism. Historically, hangover cures come and go. None have stayed the course. This study involves a pitifully small number of subjects and a lot of subjective observation. Too few women remained eligible subjects to be counted. The contributions, if any, of the other contents of the L-cysteine-containing pills are unknown. Alcohol abuse is common in Finland. The subjects’ previous experiences with alcohol were variable. Some were not able to consume all the alcohol required; some had such a high tolerance that they developed no hangover symptoms, even without L-cysteine; some were excluded because they added to the test dose by heading to a bar for more booze. Scientific rigor suggests that the journal editors might have been wiser not to accept the paper for publication. It is perhaps irrelevant that funding for the study was supplied by a company marketing L-cysteine.