A 2025 study at Tokyo Metropolitan Institute for Geriatrics and Gerontology found that applying vitamin C to aged skin flips on genes responsible for regenerating skin cells—resulting in noticeably thicker, more resilient skin.

Recent reports suggest the body absorbs up to 64% of pool chlorine through the skin, with children absorbing as much as 88%. This exposure can lead to skin irritation, dryness, and potential long-term effects like thyroid issues.