Did Anyone Check To See Whether Flossing Actually Works?

Evidence for flossing's effectiveness isn't great

Teeth with floss
A guy getting flossedWalter Siegmund | CC BY SA 2.5

I'm going to get my bias out of the way right at the start. I hate flossing. I have bad teeth, said my dentist, so despite flossing every day the right way, I still have to get cavities filled every time I go. I don't like going to the dentist. Also, used floss is one of the worst smelling things on the planet. Okay, that's out of the way:

An Associated Press investigation showed that despite being a federal government recommendation since 1979, no research proved whether flossing was actually effective or not. Those recommendations were scrapped last year.

The AP looked at the most rigorous research conducted over the past decade, focusing on 25 studies that generally compared the use of a toothbrush with the combination of toothbrushes and floss. The findings? The evidence for flossing is "weak, very unreliable," of "very low" quality, and carries "a moderate to large potential for bias."

The investigation did find some studies that showed flossing might reduce gum inflammation. The studies cited by the American Dental Association and American Academy of Periodontology "used outdated methods or tested few people," even though the ADA has been telling Americans to floss since 1908, when no one really needed to test scientifically whether or not flossing worked.

I'm not going to say you shouldn't floss. However, after reading the AP's article, I myself couldn't find unanimous recommendations about how and when to do it. The ADA says "don't jerk or snap the floss" but this dentist is clearly snapping his floss, and dentists can't agree whether before or after brushing is correct. So I am going to say: Don't take every fact you hear for granted and always ask yourself what science-based evidence is backing the decisions you make.