Inexpensive ways to whiten teeth include brushing with a baking soda and water paste once a week and eating greens such as broccoli and lettuce, and cellulose-rich foods such as celery and apples, according to Women's Health. Additionally, wearing dark-colored clothes and blue-based lipsticks makes teeth appear whiter in contrast.
Teeth whitening aims to undo the discoloration of teeth that happens through natural yellowing with age or from antibiotic or food stains, explains Women's Health. All commercial teeth bleaching techniques use peroxide because it absorbs quickly into the teeth's porous tubules to lighten them. Since the teeth's reactions to the whitening process can vary, it is important to consult a dentist before beginning a whitening process, even with over-the-counter bleaching kits.