Sodium lauryl sulfate (SLS) is a common ingredient in toothpaste that acts as a surfactant to create foam for deeper cleaning. While it is safe and not harmful when adequately formulated and qualified, there are some potential side effects of using toothpaste with SLS. These include:

Positive:

• SLS reduces bacterial plaque in the oral cavity as it binds with bacterial protein and disrupts the bond between bacteria and the tooth surface.

Negative:

• Mucosal desquamation, irritation or inflammation of oral mucosa or the dorsal part of the tongue, ulcerations, and toxic reactions in the oral cavity.
• SLS can increase the incidence of aphthous ulcers.
• SLS can limit fluoride bioavailability, which undermines one of the major benefits of brushing your teeth.
• Repetitive application may result in inflammation of the skin (contact dermatitis) .

It is important to note that these side effects are not life-threatening but require an individuals attention. Patients with recurrent aphthous ulcers may benefit from using SLS-free toothpaste in terms of decreasing the number of ulcerations, duration of the ulcerations, and the intensity of the pain caused by the ulcerations. However, further research is needed on the effect of SLS on oral and gastrointestinal systems when used in toothpaste. When it comes to choosing a toothpaste, it makes sense to select one that is SLS-free to avoid the potential downsides and maximize the oral health benefits of toothpaste.