Spit Prevents Foggy Swim Goggles

Human spit does have the potential to keep your swimming goggles fog-free.

By spitting on the lenses of your goggles before a swim, and rubbing that delicious mix of mouth bubbles around the rim, you're actually creating what science calls a "surfactant". In simple terms, what the spit does is stop moisture particles from connecting with each other on the lens of your goggles, which slows down the ability of fog to form.

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