Whiten your teeth.
Yellow teeth are no match for apple cider vinegar. For stubborn stains, rub apple cider vinegar directly on your teeth then rinse with water. Be careful not to do this too often, as it can break down tooth enamel. For a less abrasive whitening mouthwash, mix one teaspoon of apple cider vinegar with a cup of water, then swish around in your mouth.