Article: Each whitening product works slightly differently. Some have to be removed after just a few minutes. Others can be left overnight. Read instructions on the package carefully to make sure that you receive the maximum benefit without causing harm to your teeth or mouth. It is essential that you do not leave products on for longer than the recommended time.  Avoid acidic foods and drinks after use. These can hurt the effectiveness of the whitening product as well as irritate your sensitive teeth.  Repeat whitening treatments as necessary. Don't whiten your teeth too often: simply use top ups as needed every six months or so. Whitening toothpastes are a gentler, slower way to whiten teeth. They will not work as quickly or effectively as other whitening methods, though they can be a great way to preserve your desired shade of teeth once you've achieved it in other ways. Whitening toothpastes do not have bleaching agents, but rather use polishing and other chemical reactions in order to remove surface stains. Look for a whitening toothpaste that has been approved by the American Dental Association or other professional dental group in order to ensure that the product is safe and effective. Some studies show that toothpastes with baking soda might be more effective at cleaning teeth than other toothpastes. Baking soda has also long been used as a natural tooth-whitening agent; however, baking soda can also irritate your delicate skin around your mouth. A toothpaste with baking soda should have concentrations low enough that you will receive some benefit from the baking soda without experiencing irritation. There isn't solid data about the usefulness or safety of natural tooth-whitening treatments; however, some individuals report positive effects from their use. Be wary when using these treatments, and it is a good idea to talk to your dentist first. These natural treatments include the following:  Applying mashed strawberries to your teeth. Strawberries have an enzyme, malic acid, that supposedly brightens teeth. Mash fresh strawberries and apply them to your teeth. Let them sit for five minutes and then rinse.  Using lemon juice and baking soda. Shake a small amount of baking soda onto a thick fresh lemon wedge. Bite into this wedge and let it sit for a few minutes, until the fizzing subsides.  Note that strawberries and lemons both contain citric acid, which can cause your teeth to become weaker and predisposed to developing sensitivity. Use natural tooth whitening treatments with caution, and be suspicious of their claims.
What is a summary of what this article is about?
Follow package instructions carefully. Brush with a whitening toothpaste. Consider a toothpaste with baking soda. Be cautious about natural tooth-whitening treatments.