It's a no-brainer, right? You floss your teeth every day to keep them healthy. Turns out it might not be that simple.

FOX's Jack Callaghan reports:

How many times has your dentist told you, floss every day, it prevents gum disease and cavities. Maybe not, the federal government has quietly dropped a recommendation for daily flossing from their latest health guidelines.

Pressed for a reason, the Department of Health and Human Services admits the effectiveness of flossing has never been proven by research.

Even Dr. Wayne Aldredge, president of the American Academy Periodontology, admits the scientific evidence about flossing is weak, but he still advises his patients to floss anyway to help avoid gum disease.

Jack Callaghan, FOX News.