Arginine, a common amino acid found naturally in food, fights cavities and gum disease, a study shows.

The enzyme, known also as L-arginine - present in red meat, poultry, fish and dairy products - is already used in dental products for tooth sensitivity. L-arginine is also widely available in supplement form.

Now researchers from the University of Michigan have discovered in lab experiments the enzyme also can break down down dental plaque, which causes gum disease.

The U.S. Centers for Disease Control and Prevention estimates that half Americans over age 30 – nearly 65 million people – have peritonitis (gum disease.)

Gum disease leads to tooth loss, and can also introduce bacteria into the blood stream, causing inflammation, which is increasingly linked to a number of serious diseases, including heart disease, diabetes and some forms of cancer.

Most methods for dental plaque control involve antimicrobial agents, such as chlorhexidine, but they can affect sense of taste and stain teeth. Antimicrobial treatments have been the subject of debate about overuse in recent years.

It isn’t clear how L-arginine causes the disintegration of the biofilms, but the enzyme apparently can alter how plaque bacteria behave, preventing them from sticking to tooth surfaces, the researchers said.

The study is reported in the journal PLOS ONE.