Hydrogen Peroxide: A Ubiquitous Component of Beverages and Food

Hydrogen peroxide (H2O2) plays a signaling role in the body. Numerous studies demonstrated that H2O2, generated mainly by autoxidation of polyphenols, ascorbate and other reduced compounds, is a common component of beverages such as honey, tea, coffee, formulated drinks and alcoholic beverages, and is generated in cooked vegetables. It is produced in fresh milk predominantly by xanthine oxidase. The antimicrobial action of honey depends mainly on H2O2 generated by glucose oxidase and polyphenol autoxidation. Many components of beverages and food scavenge generated H2O2, so its level is a result of the balance between generation and scavenging. This review discusses the mechanisms of hydrogen peroxide formation, collects evidence for the presence and generation of H2O2 in beverages and food, discusses its fate in the gastrointestinal tract, evolutionary aspects of human exposure to alimentary hydrogen peroxide, and both adverse action and possible beneficial effects of the consumed hydrogen peroxide.