Brushing in the shower can save a couple minutes from your morning routine but, there are a couple things you may want to consider before putting a toothbrush holder next to your shampoo. The water in the shower pipes sits unmoved for most of the day allowing bacteria to flourish until the valve is opened again, resulting in water that’s 100 times more likely to harbor harmful bacteria than water from the faucet. Immediate and excessive rinsing after brushing washes away much of the toothpaste’s effects. Ideally you shouldn’t rinse excessively for about a half-hour after brushing to allow fluoride or desensitizers to be effective. Storing your toothbrush in a damp environment also allows bacteria to flourish on the bristles. Finally, and least-pleasantly, you smell molecules. Molecules are microscopic pieces of what you smell. Keep that in mind if someone forgets to put down the toilet seat!