While any type of alcohol can leave you feeling intoxicated, there are some differences in the effect dark versus clear alcohol can have on the body. The various shades come about due to the ingredients used to make them, as well as the fermentation process. And it's this process that can set the two types of alcohols apart.
"All distilled liquor starts out clear or light. Then as it is aged in barrels or similar, it ferments and takes on a darker appearance," Jamé Heskett, MD, medical expert at Fresh n' Lean, tells Bustle. "Additionally the liquor absorbs some of the substances that are present in the container that it is fermented in, i.e., 'oak barrels.' These organic compounds then end up in the liquor."
Darker alcohols may have more side effects than clear, thanks to the organic compounds and impurities — also known as congeners, in the biz — that they pick up in the production process. And as a result, "not only must you be conscious of the volume at which you are drinking but the alcohol that you are drinking," Dr. Duy Nguyen, psychiatrist at Beachway Therapy, tells Bustle. Read on below for some of the reasons why, because as it turns out, not all alcohols are created equally.
1Dark Alcohols Contain More Impurities
While it's considered safe to drink dark alcohols in moderation, they do contain a higher number of congeners, Dr. Nguyen says, which are impurities that form during the fermentation process.
"Several chemicals are produced in this process, such as acetone," Dr. Nguyen says. "If one compares whiskey to vodka, whiskey contains many times more the number of congeners than vodka."
Congeners are what give many types of dark alcohol their flavor, but they can also impact how you feel.
2Dark Alcohols Are More Likely To Cause Hangovers
In general, dark alcohols are more likely to give you a headache than clear alcohols, all thanks to the congeners.
"One congener called methanol breaks down into the toxins formaldehyde and formic acid, which can worsen a hangover," Dr. Nguyen says. So if you'd like to have a drink, but don't want a headache, a clear alcohol may be your best best.
"The color of the drink does matter," Dr. Nguyen says, pointing to a study published in the journal Alcoholism: Clinical & Experimental Research. In it, participants drank equal amounts of alcohol in either vodka or bourbon forms. Thirty three percent of the bourbon drinkers reported next-day pain while only three percent of vodka drinkers had hangovers.
"One can clearly see," Dr. Nguyen says, "that the darker liquor had more of an impact than the light."
3Dark Alcohols Contain More Toxins
While there are many different types of congeners, some of them are considered toxic. But that doesn't mean they impact everyone in the same way.
"Acetaldehyde, a congener produced when ethanol is metabolized, is a chemical far more toxic than alcohol itself and can have a profoundly negative effect on one person and affect another significantly less," Dr. Lawrence Weinstein, chief medical officer of American Addiction Centers, tells Bustle.
This doesn't mean dark alcohol is unsafe to drink, as long as it's done in moderation, but that it might make some people feel worse than others.
4Clear Alcohol Produces Fewer Hangovers
Since clear alcohol has a much lower concentration of congeners, Dr. Weinstein says, it produces hangover symptoms less frequently than darker alcohol.
That doesn't, however, mean it's impossible to get a hangover when drinking gin, vodka, or other clear alcohols.
"A good rule of thumb for liquors is that the clearer they are, the less of these substances they contain," Dr. Nguyen says. "While light-colored drinks may lessen a hangover, imbibing them is not a license to become impaired and unsafe."
5Some Dark Alcohols Protect The Stomach Lining
Some other types of congeners — which again, contribute to the flavor of the alcohol — are yeast, tannins, and sulfites. "These organic compounds are basically impurities," Dr. Heskett says. And it's possible to be sensitive to them.
But other congeners can have a protective effect. "In some cases, like the congener butanol found in [whiskey], has a protective function for the stomach lining," Dr. Heskett says.
6Dark Alcohols May Contain More Antioxidants
Due to their color, darker alcohols may contain more antioxidants, which are "generally felt to be protective," Dr. Heskett says. Think along the lines of red wines, and how many studies have shown they provide various health benefits.
7Clear Alcohol Contains Fewer Allergens
"Clear liquor is liquor that has not been fermented," Dr. Heskett says. "Higher quality clear liquors are filtered to remove any impurities. Impurities generally contribute to the taste of liquor, and this is why high quality clear liquor has little taste."
But it's also why it tends to contain fewer allergens. "Impurities in liquor are thought to contribute to an individual's reaction to liquor and may be related to allergies," Dr. Heskett says, "or to just the way their own physiology process a particular alcohol."
It can be difficult to predict, from person to person, the type of effect alcohol will have. "Data in studies regarding the impact of clear and dark liquor isn’t always consistent across individuals, meaning one person might experience [a] negative physical response to one brand of whiskey with a high level of impurities, but another may not," Dr. Heskett says. "That individual my not feel well after drinking a top quality clear liquor."
That's why, when it comes to dark and clear alcohol, it's really all about personal preference. For some, dark alcohols may cause side effects. Or they may not. And the same is true for clear alcohols. Congeners may play a role in how each alcohol affects the body, but it really does come down to the individual.
