Three Weeks Without Washing Your Gym Bottle? Here’s What’s Actually Growing Inside

Three Weeks Without Washing Your Gym Bottle? Here's What's Actually Growing Inside

That stale, plasticky taste in your gym bottle isn’t the water—it’s a microscopic bacterial fortress called biofilm. We reveal exactly what’s living inside, why it thrives in your bottle, and the specific cleaning methods backed by microbiology research that actually eliminate it.