Hello Claire. To answer your question directly, the idea that sticking to a single type of alcohol will prevent a hangover is essentially a myth. While it is a very common belief, biological research shows that the primary cause of a hangover is the total amount of alcohol you consume, not the variety or combination of drinks.
When you drink, your liver metabolizes ethanol into acetaldehyde, a toxic compound that contributes significantly to the headache, nausea, and fatigue you feel the following day. Ethanol also suppresses vasopressin, a hormone that regulates water retention, which leads to dehydration regardless of whether you drank only wine, only beer, or mixed several different spirits.
The reason many people associate mixing drinks with worse hangovers usually comes down to behavior. When switching between different beverages, such as having beer first, moving on to wine during dinner, and finishing with cocktails or shots, it becomes much harder to keep track of your total alcohol intake. Furthermore, carbonated drinks can increase the rate of alcohol absorption, and sugary cocktails can mask the strength of the alcohol, leading you to drink faster and in larger quantities.
Another factor worth considering is the presence of congeners. Congeners are chemical byproducts of fermentation and aging that give certain drinks their color and flavor. Darker liquors like bourbon, dark rum, and red wine contain significantly higher levels of congeners than clear spirits like vodka or gin. Consuming drinks high in congeners can lead to a more severe hangover, but this is due to the specific compounds in the beverage rather than mixing them together.
In short, avoiding a hangover comes down to moderation, drinking plenty of water alongside your alcohol, eating a substantial meal, and pacing yourself throughout the evening. Sticking to one drink may help you pace yourself, but it will not prevent a hangover if the total volume of alcohol consumed is high.
