Brushing will remove the harmful plaque from your teeth and gums. Frequently removing food particles from your teeth and gums prevents bacteria in the food you eat from turning into harmful, cavity causing acids.
Brushing three times a day is the minimum. If you use fluoride toothpaste in the morning and at night, you don’t have to use toothpaste during the middle of the day. Perform a simple brushing with plain water or rinse your mouth with water for 30 seconds after lunch. That should do the job.