Toothpaste tabs are made from powdered toothpaste that's condensed into tablets. They're small and solid, more closely resembling a pill than a paste. They can be packaged and shipped in recyclable glass or paper containers, negating the need for tubes—which are often made from a combination of plastics and aluminum.

Any time you combine materials, they become infinitely more difficult to recycle, so more often than not these tubes end up in landfills. (Estimates for how many we trash globally each year are well into the billions.) Some companies like Colgate's natural brand Toms of Maine are working on rolling out tubes that are completely recyclable but they likely won't be widely available for another few years.

In the meantime, recycling your tube through specialty service TerraCycle or opting for a tube-free tablet are the most eco-friendly choices when it comes to brushing.

Like gel toothpaste, toothpaste tabs come in many different flavors and varieties. When shopping around for one that will keep your pearly whites looking pearly and white, Mark B. Desrosiers, DMD, a member of the American Association of Endodontists and assistant professor at Boston University School of Dental Medicine, recommends ones that contain fluoride and an abrasive like calcium carbonate.

"I measure effectiveness in two ways, ability to remove plaque and stain without damage to the teeth, and effective delivery of fluoride to the tooth," Desrosiers tells mbg. "Along with abrasiveness, fluoride is essential. Fluoride acts to strengthen the teeth by making them more resistant to decay."

Fluoride, as you may have heard, is slightly controversial in the dental space. Since it has been found to be a developmental neurotoxicant1 in high volumes, some more holistic-leaning dentists will recommend steering clear of it (and potentially risk more cavities in the process).

The American Dental Association asserts that the naturally occurring ingredient is safe to use and essential for preventing tooth decay and cavities. The ADA seal marks products that have been shown to effectively deliver fluoride to the teeth.

Here's the kicker: You'd be hard-pressed to find a toothpaste tablet with this seal. An FDA loophole says that once a toothpaste tablet contains fluoride, it's technically a drug and needs to adhere to federal guidelines.

No matter which one you use, a tablet will never deliver quite the same mouthfeel as a gel. The texture will always be a little less full and frothy. But Abby Cannon, J.D., R.D., CDN, a dietitian and low-waste lifestyle expert who has been brushing with toothpaste tablets for years, asserts that they do "get foamy."

To activate the foam factor, she says you just need to pop one into your mouth, chew it, and start brushing. One tablet is usually enough to last her a full two-minute brushing, but she knows of some people who have better luck using two at a time.

All in all, Cannon says the switch over to tabs has been painless. Though these tablets do tend to be more expensive, she appreciates that they can often be ordered on a subscription refill model, crossing another drugstore trip off the list and saving on packaging.