
The inhibitory effects alcohol has on critical thinking is never more present than the morning after a night of partying. Though we know to drink water and eat a nutritious meal to keep ourselves from hurting the next morning, alcohol silences our better judgments and the next day we find ourselves vowing to never drink again. But have you ever wondered what exactly is causing your hangover? You might be surprised to find out that simple dehydration and “picking your poison”, has a lot less to do with how you feel than you may think.
As it turns out, our body produces a chemical during the metabolism of alcohol that makes us feel worse than alcohol would alone. When alcohol, biochemically identified as ethanol, reaches your liver, it’s met by two enzymes, and those enzymes are responsible for breaking ethanol down into less harmful byproducts to be excreted from your body (Goodsell). The first enzyme is known as Alcohol Dehydrogenase (ADH). Alcohol dehydrogenase, with the help of an NAD+ cofactor (basically a helper-enzyme), turns the ethanol into an intermediary molecule known as acetaldehyde. From there, a second enzyme called Aldehyde dehydrogenase (ALDH), breaks the acetaldehyde down into harmless acetate, which eventually leaves our bodies in the form of carbon dioxide and water (Cederbaum, 2012). However, that intermediary molecule, acetaldehyde, is 10x more toxic for our bodies than ethanol (i.e. the alcohol) would be alone (Goodsell).
So why doesn’t drinking immediately make us feel sick? Well, when our liver is healthy and working properly, ADH and ALDH are extremely efficient at converting ethanol into acetate, and the two main nutrients that allow these enzymes to function at their full potential are: vitamin B3 (Niacin) and zinc. Zinc is a vital component of ADH by holding and positioning the alcohol group on ethanol in place. Then, vitamin B3 (Niacin) constructs the coenzyme NAD+, which performs the reaction, converting ethanol to acetaldehyde, and then to the harmless form of acetate (Samir et al., 2006). But when our liver gets overloaded with the need for ethanol metabolism, ADH and ALDH begin depleting their Vitamin B3 and zinc stores, and acetaldehyde begins to accumulate in excess, amplifying its toxicity and overall detrimental effects.
This accumulation of ethanol and acetaldehyde and its tie to hangover severity is evidenced by higher concentration of these two molecules found in the urine of study participants who reported more severe hangover symptoms, compared to those who reported less severe symptoms. In this study, participants who had a higher intake of Vitamin B3 and Zinc prior to alcohol consumption had less severe hangover symptoms and lower urine concentrations of acetaldehyde and ethanol the next day, despite the study groups not having significantly different blood alcohol content (BAC) levels (Verster et al., 2019). This highlights the importance of having the nutrients that our bodies need in order to function properly. While our bodies produce the enzymes needed to metabolize ethanol (i.e. ADH and ALDH), our bodies cannot produce the minerals and vitamins like Zinc and Vitamin B3, which are needed for those enzymes to function. And understanding why we need to eat nutritious meals may change the way we treat our bodies in more ways than one.
Despite how efficient our bodies may be at metabolizing alcohol and quelling the effects of a hangover when we’re young, chronic alcohol consumption hinders this ability to keep up over time. Alcohol consumption is related to a wide range of progressive diseases and is a fifth major cause of death in men and women worldwide. The toxic effects of alcohol have been attributed to a wide range of adverse side effects in nearly every tissue in the body, including multiple cancers (Meza et al., 2022). But since alcohol consumption is synonymous with many celebratory practices with cultures across the world, it is important to understand the underlying mechanisms of how our body is treating it, in turn how that same alcohol is treating us. And what, if any, nutrients we need to ensure we’re getting if we do decide to indulge every once in a while.
Works Cited
Cederbaum, Arthur I. “Alcohol Metabolism.” Clinics in Liver Disease, vol. 16, no. 4, Nov. 2012, pp. 667–685, https://doi.org/10.1016/j.cld.2012.08.002.
Goodsell, David. “Virtuelle (Nano) Welten: PDB Molecule of the Month 13: Alcohol Dehydrogenase.” Bioc.uzh.ch, 2025, plueckthun.bioc.uzh.ch/nanowelt/Molekuele/013_ADH/pdb13_1.html. Accessed 3 Feb. 2025.
Meza, Victor. “Alcohol Consumption: Medical Implications, the Liver and Beyond.” Alcohol and Alcoholism, vol. 57, no. 3, 2022, https://doi.org/10.1093/alcalc/agac013.
Samir Zakhari. “Overview: How Is Alcohol Metabolized by the Body?” Alcohol Research & Health, vol. 29, no. 4, 2006, p. 245, pmc.ncbi.nlm.nih.gov/articles/PMC6527027/.
Verster, Joris, et al. “Dietary Nutrient Intake, Alcohol Metabolism, and Hangover Severity.” Journal of Clinical Medicine, vol. 8, no. 9, 27 Aug. 2019, p. 1316, https://doi.org/10.3390/jcm8091316. Accessed 11 May 2021.