Using your own water bottle can keep 92 plastic ones from heading to the landfill each year, but make sure to keep it clean. If that bottle has a cap with a spout, your hands could corrupt it with germs when you pull it open.
The solution: Wash the bottle often, especially the cap, Gerba says. If you’re sharing it, wash it after each use. Even better, use a bottle with a screw top, which doesn’t pose as big a threat for germs.