Up to 12 hours of lasting fresh breath is based on In-vivo study with regular use over 4 weeks Kill the bacteria that cause bad breath with Closeup Deep Action Eucalyptus Mint Gel toothpaste. Bad breath can be caused by the millions of bacteria that live in your mouth. If you don't brush and floss every day, plaque germs can form. Closeup gel toothpaste helps kill the bacteria and helps prevents bad breath. Brushing with Closeup gel toothpaste is one simple step you can incorporate into your daily routine to help keep your mouth healthy, and it can have a positive effect on your oral health.