Bacteria are made of proteins, and proteins hate being overheated—kind of like me in a crowded subway. When you boil water, the heat denatures those proteins, which is a fancy way of saying they curl up and stop working.
Without their proteins, bacteria die instantly. It’s not a slow, dramatic death—it’s more like flicking off a light switch.
And poof—your water is now safe to drink. No microscope required.
Does It Kill Everything?
Here’s the honest truth: boiling kills almost all the bad guys. We’re talking about 99.999% of bacteria, viruses, and parasites. That’s a five-star kill rate.
But—and this is a tiny but—some sneaky bacterial spores can survive boiling. Think of spores as bacteria in hibernation mode, like a bear in a cave.
Don’t panic! Spores are usually harmless unless you’re a zombie apocalypse survivor. For everyday water, boiling is more than enough to keep you safe.
