Hormone Disruptors Found in Toothpastes: What You Need to Know

Every day, most of us brush our teeth at least twice, often without thinking about what’s inside our toothpaste or mouthwash. While oral care products are designed to protect teeth and gums, some ingredients have raised concerns for their potential to interfere with the body’s hormonal balance.

These substances are known as hormone disruptors, or endocrine-disrupting chemicals (EDCs). Because oral care products are used daily and absorbed through the oral mucosa, even low-level exposure may matter over time.

This article explains what hormone disruptors are, how they affect the body, and which ingredients commonly found in toothpaste and mouthwash may act as hormone disruptors.

What Are Hormone Disruptors?

Hormone disruptors, scientifically referred to as endocrine-disrupting chemicals, are substances that interfere with the endocrine system — the body’s network of glands and hormones that regulate metabolism, growth, reproduction, mood, and immune function.

These chemicals can:

• Mimic natural hormones (such as estrogen)
• Block hormone receptors
• Alter hormone production, transport, or breakdown
• Disrupt feedback loops in hormone regulation

Because hormones act at extremely low concentrations, even small disruptions may lead to measurable biological effects over time.

How Do Hormone Disruptors Affect the Body?

The endocrine system plays a central role in overall health. Scientific research has linked endocrine disruptors to a wide range of effects, including:

• Thyroid dysfunction
• Reproductive and fertility issues
• Altered menstrual cycles
• Reduced sperm quality
• Developmental effects in children
• Metabolic changes
• Hormone-sensitive cancers

Importantly, exposure is often chronic and cumulative, meaning daily use products — like toothpaste and mouthwash — deserve closer scrutiny.

Hormone-Disrupting Ingredients Found in Oral Care Product

1. Triclosan

Triclosan is one of the most well-studied endocrine disruptors historically used in toothpaste and antibacterial mouthwashes.

Research shows that triclosan:

• Has a chemical structure similar to synthetic estrogens
• Can interact with estrogen and androgen receptors
• Disrupts thyroid hormone regulation
• Interferes with steroid hormone production

A comprehensive review of human and animal studies found that triclosan exposure is associated with altered reproductive hormone levels, impaired fertility markers, and potential effects on embryonic development.

Triclosan has also been detected in human urine, blood, breast milk, and amniotic fluid, confirming systemic absorption following repeated exposure.

👉 Although triclosan has been removed from many consumer soaps, it has historically been permitted in some toothpastes due to its antibacterial properties.

2. Fluoride (Hormonal Considerations)

Fluoride is widely used to prevent tooth decay, but its relationship with the endocrine system — particularly the thyroid gland — has been debated in scientific literature.

Several studies suggest that excessive or chronic fluoride exposure may:

• Interfere with iodine uptake
• Alter thyroid hormone levels
• Affect thyroid-stimulating hormone (TSH)

You can explore this topic in more detail here:
→ Fluoride Affecting the Thyroid
→ Fluoride and Its Effects on the Body

This does not mean fluoride should automatically be avoided by everyone, but it highlights the importance of dose, individual susceptibility, and cumulative exposure.

3. Sodium Lauryl Sulfate (SLS)

Sodium lauryl sulfate is a foaming agent commonly used in toothpaste. While not classically categorized as a hormone disruptor, SLS may indirectly affect hormonal balance through:

• Irritation of oral tissues
• Increased mucosal permeability
• Enhanced absorption of other chemicals
• Inflammatory responses that can influence endocrine signaling

For individuals with sensitivities, this can be particularly relevant.

→ If you want to know more about this ingredient, read this article: “Sodium Lauryl Sulfate in Toothpaste: Is It Safe?”

4. Parabens

Parabens are preservatives sometimes found in toothpaste and mouthwash. They are known to mimic estrogen, earning them classification as endocrine disruptors.

Studies have detected parabens in human tissues and fluids, and their estrogen-like activity raises concerns about long-term hormonal effects, especially with daily exposure.

Common examples include:

• Methylparaben
• Propylparaben

5. “Fragrance” and Hidden Phthalates

The term fragrance or parfum on an ingredient label can mask a mixture of chemicals, including phthalates, which are well-documented endocrine disruptors.

Phthalates have been linked to:

• Altered reproductive hormone levels
• Reduced sperm quality
• Developmental effects

Because they are not always disclosed individually, they are difficult for consumers to identify.

6. Alcohol and Antibacterial Agents in Mouthwas

Some antibacterial or alcohol-based mouthwashes contain ingredients that may:

• Disrupt the oral microbiome
• Increase mucosal absorption of chemicals
• Contribute to systemic exposure of endocrine-active substances

Choosing alcohol-free formulations with transparent ingredient lists can help reduce unnecessary exposure.

Why Oral Care Products Deserve Special Attention

Unlike many cosmetics, oral care products:

• Are used multiple times per day
• Come into contact with highly absorbent tissues
• May be partially ingested
• Are often used from early childhood

This makes ingredient quality and formulation especially important.

How to Reduce Exposure to Hormone Disruptors in Oral Car

• Read ingredient labels carefully
• Avoid triclosan, parabens, and vague “fragrance” listings
• Consider SLS-free options if you have sensitivities
• Be mindful of total fluoride exposure from all sources
• Choose brands that prioritise transparency and evidence-based formulation

Final Thoughts

Hormone disruptors in oral care products are not always obvious, but growing scientific evidence suggests that repeated, low-level exposure may influence hormonal balance over time.

Being informed allows you to make better choices — not out of fear, but out of understanding. Oral health and overall health are deeply connected, and what we use every day matters.

Reference

• Marques, A. C., Mariana, M., & Cairrao, E. (2022). Triclosan and its consequences on the reproductive, cardiovascular and thyroid levels. International Journal of Molecular Sciences, 23(19), 11427. https://doi.org/10.3390/ijms231911427.
• Costa, N. O., Forcato, S., Cavichioli, A. M., Pereira, M. R. F., & Gerardin, D. C. C. (2020). In utero and lactational exposure to triclocarban: Age-associated changes in reproductive parameters of male rat offspring. Toxicology and Applied Pharmacology, 401, 115077. https://doi.org/10.1016/j.taap.2020.115077.
• Maksymowicz, M., Ręka, G., Machowiec, P., & Piecewicz-Szczęsna, H. (2022). Impact of triclosan on female and male reproductive system and its consequences on fertility: A literature review. Journal of Family & Reproductive Health, 16(1), Article 8592. https://doi.org/10.18502/jfrh.v16i1.8592.
• De Coster, S., & Van Larebeke, N. (2012). Endocrine-disrupting chemicals: Associated disorders and mechanisms of action. Journal of Environmental and Public Health, 2012, Article 713696. https://doi.org/10.1155/2012/713696.
• Lee, I., & Ji, K. (2022). Identification of combinations of endocrine disrupting chemicals in household chemical products that require mixture toxicity testing. Ecotoxicology and Environmental Safety, 240, 113677. https://doi.org/10.1016/j.ecoenv.2022.113677.