Certain foods and drinks - especially those high in carbohydrates and sugars - spur the creation of certain bacteria in your mouth that attack your tooth enamel for at least twenty minutes after you eat a meal or have a snack. By brushing teeth right after you eat, you will get rid of bacteria before they attack your tooth enamel.
For the best results, you should use a fluoride toothpaste containing fluoride to prevent tooth decay and triclosan to reduce plaque and gingivitis, ensuring that your teeth stay squeaky clean after you eat.
However, you should know that brushing teeth after eating can sometimes affect your tooth enamel too. According to an article published in the Journal of Indian Society of Pedodontics and Preventive Dentistry, if you've consumed anything acidic, you should avoid brushing your teeth for at least 30 minutes. Foods containing citric acid, like oranges, grapefruits and lemons, weaken tooth enamel. Brushing too soon after eating them can damage the enamel in its weakened state.
Consequently, it's a good idea to brush your teeth before eating an acidic food and to drink a glass of water when you are finished, to wash away the acids. As an alternative to waiting to brush your teeth, try eating nutritious foods that are low in carbohydrates and sugar after eating something acidic. This will help reduce the harmful effects that such foods create.
In addition, according to the Indian Dental Association, prolonged exposure to phosphoric acid - which can be found in soft drinks like soda and diet soda - can erode hard tissues from the tooth surface. Acid erosion causes permanent damage to your teeth. To keep acid erosion to a minimum, limit snacking between meals and be mindful of consumption of soft drinks and sugary snack foods.