Prone to Canker Sores? ARU’s SLS-Free Toothpaste May Help

You’ve vetted your supplements, scrutinized your skincare, and probably banished most of the seed oils from your kitchen. But the toothpaste you’re using twice a day, every day, has somehow escaped the same scrutiny.

ARU toothpaste is part of a new generation of oral care built for people who actually read the back of the box — shorter formulas, ingredients with a purpose and evidence behind the choices.

Conventional toothpaste tubes carry 15 to 20+ ingredients, many of which exist for foam, color or shelf appeal rather than dental outcomes. The pushback consumers have applied to food, beauty and cookware is finally reaching oral care, and the data behind cleaner formulations is more substantial than the category’s marketing has historically let on.

Making a Case for SLS-Free Toothpaste

Sodium lauryl sulfate, or SLS, is the foaming agent in most conventional toothpastes. It’s the reason your brush feels productive. It’s also a detergent originally developed for industrial cleaning, regulated as safe at toothpaste concentrations but well-documented as an irritant to soft tissue and a contributor to canker sores.

A 2019 systematic review in the Journal of Oral Pathology & Medicine found that SLS-free toothpaste reduced the number of ulcers, duration of ulcer, number of episodes and ulcer pain.

“Minor changes in a toothpaste can really make a difference in a patient’s quality of life,” Diana Messadi, a professor and the chair of oral medicine, oral pathology and orofacial pain at the UCLA School of Dentistry, told The Washington Post.

If you’ve quietly written off canker sores as bad luck, switching to an SLS-free toothpaste is one of the cheaper experiments you can run.

What’s Actually In Every ARU Toothpaste Formula

The ARU toothpaste line comes in four different formulas. None of them contain SLS. They’re also free from microbeads, dyes, parabens, phthalates, triclosan, fluoride, artificial flavors and animal testing.

They each share eight ingredients in common, all of which serve a specific purpose:

1. Cocamidopropyl betaine, a coconut-derived surfactant that creates gentle foam and lifts away plaque and debris without irritating gum tissue (an SLS alternative).
2. Sorbitol, a natural sugar alcohol that sweetens the formula and keeps it from drying out.
3. Cellulose gum, a plant-derived thickener that keeps the paste smooth, stable, and evenly textured.
4. Silica. a naturally occurring mineral that adds texture and gently scrubs away plaque and surface stains.
5. Natural mint flavors, a blend of eucalyptus, spearmint, and peppermint oils for flavor and fresh breath.
6. Potassium sorbate, a preservative that prevents mold, yeast, and bacterial growth in the tube.
7. Stevia rebaudiana leaf extract, a natural, zero-calorie sweetener that rounds out the flavor without contributing to decay.
8. Aqua (water), the solvent that dissolves and binds the other ingredients into a paste.

Three of the formulas add one more ingredient to the mix, while the fourth adds three. Those ingredients are specifically chosen to either whiten teeth, reduce sensitivity, improve gum health or protect cavities.

Here’s a breakdown:

1. The fluoride-free whitening toothpaste adds sodium bicarbonate (baking soda) to polish away surface stains, calcium carbonate as a gentle abrasive for plaque and calcium peroxide to break down deeper stains through slow oxidation.
2. The fluoride-free sensitive toothpaste adds hydroxyapatite, the same mineral that makes up natural tooth enamel, to remineralize teeth and fill in the micro-fissures that cause hot, cold, and sweet sensitivity.
3. The gum health toothpaste adds stannous fluoride, which strengthens enamel while also reducing the bacterial overgrowth and nerve stimulation that lead to bleeding and inflamed gums .
4. The cavity protection toothpaste adds sodium fluoride, the standard cavity-fighting active, which remineralizes enamel and increases its resistance to the acid erosion that causes decay.

Fluoride-Free Toothpaste: What the Evidence Says

The scientific consensus is clear. Fluoride is safe at the concentrations used in commercial toothpaste, and the American Dental Association still recommends fluoride toothpaste for daily use.

“The fluoride will help reduce the demineralization process, which is the first stage of tooth decay,” says Dr. David Okano, a periodontist and assistant professor at the University of Utah School of Dentistry. “Also, if you have the demineralization but not yet a full-blown cavity in the tooth, the fluoride can be taken up into that demineralized area to help it remineralize.”

A growing share of consumers still skip it. The most established concern is dental fluorosis, a cosmetic condition that develops when young children ingest too much fluoride while permanent teeth are still forming, which is why kids toothpaste choices warrant extra scrutiny. Some adults also report sensitivity or irritation from fluoride formulas. Others simply prefer shorter ingredient lists.

ARU’s line covers both lanes, so a fluoride-free toothpaste and a remineralizing toothpaste with hydroxyapatite sit alongside the two fluoride picks.

Hydroxyapatite Toothpaste as a Remineralizing Alternative

The most evidence-supported fluoride alternative is hydroxyapatite, the same mineral that makes up natural tooth enamel. As a remineralizing toothpaste ingredient, it fills the micro-fissures that cause hot, cold, and sweet sensitivity and rebuilds enamel from the surface in.

ARU’s sensitive formula is a hydroxyapatite toothpaste — a credible toothpaste for sensitive teeth that doesn’t rely on fluoride to do the work. If you’ve been looking for a clinical reason to avoid fluoride beyond preference, remineralization via hydroxyapatite is the answer with the most data behind it.

The Honest Worth-It Verdict

Pick by goal. Want whiter teeth, go with whitening. Bleeding gums, gum health. Standard daily protection, cavity protection. Sensitive teeth, the hydroxyapatite formula. All four are available at Walmart and on Walmart.com.