Alcohol does not directly cause vitamin C serums to oxidize faster, but alcohol exposure is known to increase oxidative stress in biological systems, which can conceptually relate to oxidation processes. However, the specific interaction between alcohol and vitamin C serums in topical skincare products has not been directly studied or documented in authoritative medical literature.
Vitamin C serums contain ascorbic acid, a molecule highly sensitive to oxidation when exposed to air, light, heat, or metal ions. Oxidation of vitamin C serums leads to a loss of potency and changes in color and smell. The main factors accelerating this oxidation are environmental, such as exposure to oxygen and light, rather than the presence of alcohol in the serum or on the skin.
From a biochemical perspective, alcohol (ethanol) is a small molecule that can act as a solvent or carrier in cosmetic formulations, but it is not a strong oxidizing agent. In fact, alcohol is often used in skincare products to help stabilize formulations or enhance penetration. The oxidation of vitamin C in serums is primarily driven by reactive oxygen species (ROS) and metal-catalyzed reactions, not by ethanol itself.
Medical and biochemical research shows that chronic alcohol consumption increases oxidative stress in the body by generating reactive oxygen species and impairing antioxidant defenses. This oxidative stress contributes to cellular damage and diseases such as neurodegeneration and liver disease [1][2][6]. However, this systemic oxidative stress is different from the chemical stability of vitamin C in a topical serum.
Vitamin C is an antioxidant that neutralizes free radicals by donating electrons, and it can be regenerated by other antioxidants such as vitamin E [5]. In skincare, formulations often combine vitamin C with stabilizers and antioxidants to prevent rapid oxidation. Alcohol in the formulation does not inherently accelerate vitamin C oxidation; rather, exposure to air, heat, and light are the main culprits.
In summary, while alcohol consumption increases oxidative stress in the body, there is no authoritative evidence that alcohol causes vitamin C serums to oxidize faster when applied topically or stored. The oxidation of vitamin C serums is mainly influenced by environmental factors and formulation stability rather than the presence of alcohol. If alcohol is present in a serum, it is typically as a solvent or preservative and does not chemically promote oxidation of vitamin C.
Sources:
[1] Nature Communications, 2025: Alcohol addiction and Alzheimer’s disease molecular pathways
[2] PMC, 2025: Ethanol-induced oxidative stress and neurodegeneration
[5] Frontiers in Nutrition, 2025: Vitamin C and E co-administration in oxidative injury
[6] Tandfonline, 2025: Ethanol exposure triggers oxidative stress in organs
