Toothpaste may seem harmless, but many popular brands contain ingredients that have raised serious health concerns. Research-backed data reveals that harmful ingredients like sodium lauryl sulfate (SLS), triclosan, fluoride (in excess), propylene glycol, parabens, and artificial sweeteners or dyes may cause adverse effects ranging from skin irritation and ulcers, to hormonal disruption, neurotoxicity, and potential links to cancer.
Several of these compounds are classified as endocrine disruptors or flagged for their potential to cause organ damage, developmental concerns in children, or contribute to antibiotic resistance. Even ingredients marketed for cavity prevention, like fluoride, carry risks if swallowed in high amounts—particularly by young children.
This article “Harmful Ingredients in Toothpaste” presents only the facts, citing clinical studies, toxicology reviews, and data from agencies like the FDA, CDC, and WHO. If you’re looking for a science-based breakdown of what’s inside your toothpaste and why it matters, you’ll find everything you need right here.
1. Sodium Lauryl Sulfate (SLS)
What it is: A detergent and surfactant used to create foam.
Why it’s concerning:
- A study published in the Journal of the American College of Toxicology found that SLS can cause skin irritation in concentrations as low as 0.5% and becomes increasingly irritating with higher concentrations (Vol. 2, No. 7, 1983).
- Research in the Journal of Oral Pathology & Medicine found that SLS may increase the frequency of recurrent aphthous ulcers (canker sores) in some individuals (Herlofson & Barkvoll, 1996).
2. Triclosan
What it is: An antibacterial and antifungal agent once commonly used in toothpaste.
Why it’s concerning:
- Although Colgate Total with triclosan was FDA-approved, the FDA later banned triclosan in over-the-counter antiseptic products in 2016 due to insufficient evidence of long-term safety.
- A 2017 study in Environmental Science & Technology noted that triclosan disrupts the gut microbiome and may contribute to antibiotic resistance (Zhang et al.).
- The Endocrine Society has identified triclosan as an endocrine-disrupting chemical (EDC).
3. Fluoride (in excessive amounts)
What it is: A mineral used to strengthen enamel and prevent cavities.
Why it’s concerning:
- While fluoride is effective for dental health, excessive ingestion—particularly in children—can lead to dental fluorosis.
- According to the CDC, children under six who swallow toothpaste with fluoride regularly are at risk of mild to moderate fluorosis.
- A 2019 study published in JAMA Pediatrics associated higher prenatal fluoride exposure with lower IQ scores in children, though the topic remains debated.
4. Artificial Sweeteners and Dyes
What they are: Ingredients like saccharin, aspartame, and colorants such as Blue 1 and Red 40.
Why they’re concerning:
- Saccharin was once linked to bladder cancer in rats, though later human studies reduced this concern; it remains controversial.
- Aspartame has been scrutinized for potential neurological effects; a 2023 WHO report classified it as “possibly carcinogenic,” although not conclusively.
- The Center for Science in the Public Interest (CSPI) has flagged artificial dyes like Red 40 and Yellow 5 for potential behavioral effects in children and possible allergic reactions.
5. Propylene Glycol
What it is: A humectant used to retain moisture.
Why it’s concerning:
- Used in antifreeze and cosmetics, propylene glycol can cause allergic reactions and skin irritation.
- The Agency for Toxic Substances and Disease Registry notes potential liver and kidney effects in high exposures, though low levels in toothpaste are generally considered safe.
6. Parabens
What they are: Preservatives used to prevent microbial growth.
Why they’re concerning:
- Parabens are known endocrine disruptors. A 2004 study in Journal of Applied Toxicology detected parabens in breast cancer tissue, though causal links were not established.
- Methylparaben and propylparaben are the most commonly found in dental products.
Final Notes on Ingredient Transparency
According to a 2020 survey conducted by the Environmental Working Group (EWG), more than 60% of consumers are unaware of the full list of ingredients in their personal care products, including toothpaste. Transparency and regulatory scrutiny remain key concerns.
Conclusion of Harmful Ingredients in Toothpaste:
Understanding the data behind common toothpaste ingredients is essential for informed decision-making. While regulatory agencies monitor many of these substances, ongoing research suggests a need for caution and ingredient awareness—especially for vulnerable populations like children and pregnant women.