Microplastics in Food and Drinking Water: Evidence on Dietary Exposure, Gut Health, Metabolic Risk, and Safer Food-Contact Packaging

Microplastics have been reported in bottled water, tap water, table salt, seafood, packaged foods, and many commercially sold beverages. This makes long-term dietary exposure an important food-safety question. This structured narrative mini-review focuses on two linked questions: where food- and water-borne microplastics are most often reported, and what present research suggests about possible gut and metabolic effects. The review gives special attention to food-contact packaging because it is one of the few parts of this exposure pathway that companies can directly redesign, test, and regulate.Peer-reviewed literature from 2010 to 2025 was organized into five evidence layers: packaging context, occurrence studies in food and drinks, packaging-related release studies, gut and metabolic health studies, and implications for safer packaging practice. Across the retained literature, bottled water and plastic-packaged beverages often show higher or more variable particle counts than tap water, while salt and seafood also appear repeatedly as important contributors. Packaging-related evidence suggests that polymer type, storage duration, heat, cap friction, abrasion, and repeated handling may influence particulate release.The health evidence is less settled than the exposure evidence. Recent reviews, experimental studies, and limited human data suggest that ingested microplastics may affect gut barrier integrity, microbial balance, oxidative stress, inflammatory signaling, and possibly metabolism, but direct human clinical proof remains limited and not fully consistent. The most careful conclusion at present is that dietary exposure occurs, while the size of the human health risk remains uncertain because analytical methods, particle-size cutoffs, contamination controls, and real-world dose estimates vary widely across studies. Even with this uncertainty, the packaging literature supports a precautionary approach: better particulate-release testing, standardized reporting, realistic stress testing, and safer-by-design food-contact materials.