Owners of aluminium-case Apple Watches may want to consider how their body chemistry could affect the device's long-term durability.
Images shared in an online forum show a six-year-old Apple Watch with extensive pitting and elongated grooves across the casing and its openings.
The damage appears consistent with pitting corrosion, a localized form of metal degradation.
Commenters suspect the wearer's sweat triggered the reaction, with chloride ions from sodium breaking through the aluminium's protective oxide layer.
Once exposed, the underlying metal reacts with additional chloride ions, creating a localized acidic environment that eats further into the case.
Some observers also questioned whether lotions or skin creams may have contributed to the wear.
The case appears to be an isolated incident rather than a widespread defect, as sweat composition and volume vary significantly between individuals.
Corrosion from bodily fluids is not unique to smartwatches; traditional watchmakers have long tested cases against artificial sweat to measure chemical resistance.
No support documentation specifically addresses sweat-related corrosion for the Apple Watch.
Standard care guidance recommends regular cleaning and notes precautions for users with skin sensitivities or allergies.
