Dentists say that leaving toothpaste uncapped can affect your oral health. So what actually happens if you leave toothpaste uncapped?

Attract bacteria

According to Dr. Bill Dorfman, dentist at DDS Century City Aesthetic Dentistry (USA), an open toothpaste tube is a "breeding ground for bacteria."

Similarly, Dr. Lauren Becker, a dentist at Lauren Becker Dental (USA), also explained: Leaving toothpaste tubes open, uncapped, or loosely capped can attract bacteria. This can affect overall health. For example: If you leave toothpaste tubes uncapped in the bathroom, bacteria in the toilet can enter.

What's more, according to Dr. Dorfman, research has found both bacteria and fungi growing in uncapped toothpaste.

Bacterial growth can lead to oral health problems like cavities, gingivitis, and bad breath, says Dorfman. Those problems, including plaque, can lead to more serious health problems like heart disease.

The cream is dry.

Dentists also say that leaving toothpaste uncapped can cause it to dry out, and no one likes that hard, sticky feeling on their teeth.

Leaving the cap on can cause the toothpaste to dry out and become more difficult to use, says dentist Jeffrey Sulitzer, clinical director of SmileDirectClub Dentistry.

Less effective

In addition to drying out, opening the lid also reduces the effectiveness of the toothpaste.

Dr. Lior Tamir, DDS, a cosmetic dentist in San Mateo, explains that when the cap is opened, the toothpaste dries out and oxidizes.

This can make the active ingredients in the toothpaste less effective, which can make the toothpaste less effective at removing plaque, restoring and reducing cavities, warns expert Tamir.

This is especially important for toothpastes that contain fluoride, notes Dr. Dorfman.

Fluoride can break down when exposed to air, light or heat, leaving toothpaste unable to protect teeth from cavities and other oral health problems, says Dorfman.

Dentists agree: Keep the cap on the toothpaste tube. Additionally, Tamir recommends keeping an eye on expiration dates — something people often overlook, according to Best Life .