Water intake during drinking does not alleviate hangover symptoms

Hangovers can impair the ability to drive a car or work in industrial settings, in addition to causing unpleasant symptoms such as headaches and fatigue. As for reducing hangover symptoms, the effect of consuming water between drinks, often referred to as a "chaser," has been empirically recognized; however, this effect has not been verified to date. The purpose of this study was to clarify whether intermittent drinking of water during alcohol consumption affects the ethanol and acetaldehyde kinetics in the body and whether it alleviates hangover symptoms with the psychomotor function test and subjective symptoms on the following day.

Thirteen healthy Japanese adult males with wild-type aldehyde dehydrogenase (ALDH)2 (ALDH2 *1/*1) were included in this study. The trial design was a randomized, 2×2 crossover study in which subjects drank (1) sake equivalent to 1.3 g/Kg body weight of pure alcohol (Control group) and (2) the same amount of sake and 15 mL/Kg body weight of water (Water group) intermittently, each at a constant pace over 1 hour. Before drinking, immediately after drinking, and at various times up to 15 hours after, we measured ethanol and acetaldehyde concentrations in the expired air, administered the Digit Symbol Substitution Test (DSST), and evaluated the subjective intoxication symptom score (VAS). Breath ethanol and acetaldehyde concentrations were determined by sensor gas chromatography. Differences in breath concentrations and pharmacodynamic indices between the two groups were evaluated using a linear mixed-effects model with fixed effects for the test beverages and the number of administrations, and random effects for the subjects.

No differences were observed between the two groups in the kinetics of exhaled ethanol and acetaldehyde. The DSST scores were similar between them. The VAS assessed subjective symptoms of facial flushing, headache, nausea, concentration, sleepiness, and mood elevation, and no differences were found between the two groups.

The intermittent addition of drinking water during ethanol consumption did not significantly alter ethanol disposition or pharmacodynamic parameters, suggesting it did not affect hangover symptoms.