Microbiologists say there’s a tipping point when simply rinsing is no longer safe for your health. I regularly rinse my gym water bottle with some water before refilling it again for another day, but I sometimes worry about how gross this habit is. When I asked experts about how long I can safely go without properly cleaning my water bottle, they were pragmatic but firm. You don’t need to clean your water bottle with soap and water after every single use ― but there’s a tipping point when