After researching a new toothpaste called Dentisse Natural Reflection, I became curious about what exactly I should be looking for in a toothpaste. What is the magic component that fights cavities, tartar and plaque? And is there anything that should send up red flags when skimming through the ingredients on the back of my toothpaste tube?

The most obvious place for me to start my research was the American Dental Association’s website. Most dentists recommend only ADA-backed toothpastes and most major brands (including Colgate and Proctor & Gamble’s Crest) have been approved. According to the website, all ADA-accepted toothpastes contain fluoride and none contain sugar; other than those two rigid standards, the ADA allows flexibility with regards to ingredients, which may include abrasives that remove debris, humectants that stop toothpastes from losing water, flavoring/sweeteners, thickening components and detergents which create foam.

But before I get into all that, I should elaborate on fluoride and the controversy that surrounds the ingredient. According to the ADA, fluoride strengthens enamel and removes plaque, which can lead to disease and tooth decay. One report gathered 74 studies about fluoride in dentistry and concluded that the benefits of the ingredient are “supported by more than half a century of research,” and that fluoride does indeed prevent cavities. Another study proved that less tooth deterioration was shown in “the presence of fluoride toothpaste than in the presence of the non-fluoride toothpaste with an otherwise identical formulation.”

So why is it that there has been a backlash against fluoride? There are several reasons, but the primary one is concern about fluoride’s toxicity. While children are the ones who are most at risk of dental fluorosis, which is caused by excessive fluoride intake and can appear as white streaks on teeth or even black, stained and cracked teeth, anyone can be poisoned if even small amounts of toothpaste are swallowed consistently. Also, because tap water is often treated with fluoride, many people are weary of the possibility of ingesting too much. Dentisse is just one example of a toothpaste that doesn’t contain fluoride; another popular brand is Tom’s of Maine.

There are other ingredients to be on the look out for, as well. Saccharin, which gives toothpaste its sweet taste, has been linked to cancer in rats by several studies. However, there is no clear evidence that it is linked to cancer in humans. An ingredient that I personally like to avoid is sodium lauryl sulfate; not only is it an irritant, but also it has been linked to canker sores (also known as aphthous ulcers, which I am unfortunately prone to) by several studies. Finally, triclosan, an ingredient used to kill bacteria and prevent gingivitis has been the subject of some scrutiny. While studies have found that it kills harmful germs in the mouth, it is important to note that some research has linked triclosan to hormonal alterations in animals. The FDA is currently reviewing various studies regarding the safety of the ingredient, and will make its findings public in spring 2011.