Brushing is the most effective method for removing harmful plaque from your teeth and gums. Removing debris from your teeth and gums in a timely manner prevents cavity causing acids from bacteria in your food.
Brushing three times a day is the recommended minimum. If you use a fluoride toothpaste in the morning and before bed at night, you can get away without using toothpaste during the middle of the day. A simple brushing with water or rinsing your mouth with water for 30 seconds after lunch is generally sufficient.