Human stomach acid is typically 1.0 to 2.0, meaning that it has an impeccably strong pH. In a study, scientists found that the “thickened back of a single-edged blade” dissolved after two hours of immersion in stomach acid.
True, hydrochloric acid in the stomach is a potent substance. Human blood has a pH of about 7.4, whereas stomach acid has a pH of 1 to 2. That indicates it’s a powerful acid, however our “gastric juice” is a complex cocktail of secretions, not simply acid.
Metal corrosion by stomach acid was examined in vitro, which means “outside the body in a mimicked environment since a razor blade in your stomach would do a lot of damage.” According to Paul K. Li et al study, razor blade corrosion happens rather quickly in the healthy stomach. ” According to the study, double-edged blades become weak and readily broken after 24 hours, with just 63% of the blades original mass.
Reference: Li PK, Spittler C, Taylor CW 3rd, Sponseller D, Chung RS. In vitro effects of simulated gastric juice on swallowed metal objects: implications for practical management. Gastrointest Endosc. 1997 Aug;46(2):152-5. doi: 10.1016/s0016-5107(97)70064-6. PMID: 9283866.