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Can food additives found in chewing gum and toothpaste cause cancer?

A common food additive called titanium dioxide (TiO2) is what often gives toothpaste and gum their pure white look. Found in many processed foods and personal care items, TiO2’s impact on gut microbiota composition and function may also be harmful. 

What is Titanium Dioxide?

  • A nanoparticle food additive used in food and personal care products.
  • Typically used to enhance colour or make lighter foods appear white, shiny, and attractive.
  • Changes the appearance and texture of food and personal care items.

Titanium Dioxide in Canada

In Canada, titanium dioxide is not required to be explicitly listed on food product ingredients and can be listed simply as “colour”.

In a comment to the National Post, a Health Canada spokesperson indicated that manufacturers will be required to list food colouring agents like titanium dioxide starting in December of 2021. Health Canada also indicated that if new research indicating safety concerns with titanium dioxide become available, it would consider making changes to the list of approved additives.

Research Study

Some research has shown that when ingested by rats, titanium dioxide can accumulate in the liver, spleen, kidney, and lungs and can damage the liver and heart muscle.

Titanium dioxide can cause a biofilm to form in the gut and intestines. Biofilms secrete harmful bacteria to help themselves grow and can inhibit the immune system’s ability to fight infectious bacteria. In fact, biofilms are often present in infections that are resistant and hard to treat.  

According to a paper released in May 2019, titanium dioxide may be linked to certain cancers and stomach ailments.

The aim of the study was to “establish the effects of food grade TiO2 on gut homeostasis in vivo.” 

For up to four weeks, three groups of mice were fed a regular diet and water containing titanium dioxide. Groups one and two were fed 10 mg per kg of body weight each—approximately the same amount humans ingest each day. The third group of mice was fed a more toxic amount: 50 mg per kg of body weight each day.

The Results

According to the authors, “The team investigated the impact of food grade TiO2 on gut microbiota of mice when orally administered via drinking water. While TiO2 had minimal impact on the composition of the microbiota in the small intestine and colon, we found that TiO2 treatment could alter the release of bacterial metabolites in vivo and affect the spatial distribution of commensal bacteria in vitro by promoting biofilm formation. We also found reduced expression of the colonic mucin 2 gene, a key component of the intestinal mucus layer, and increased expression of the beta defensin gene, indicating that TiO2 significantly impacts gut homeostasis. These changes were associated with colonic inflammation, increased macrophages as well as increased expression of inflammatory cytokines. These findings collectively show that TiO2 is not inert, but rather impairs gut homeostasis which may in turn prime the host for disease development.”

While the study on animals does not definitively reflect how titanium dioxide effects humans or prove that it is dangerous, it did show that a biofilm formed in the large intestine of mice in all three groups. More broadly, this film is known to cause chemical imbalances in the gut that are linked to colorectal concern, intestinal swelling, and bowel diseases.

It is important to note that stomach chemical regulating stomach microbiota found in the large intestine is different in each individual person. Some people are more tolerant to titanium dioxide (and other additives) than others.”

Elsewhere, in France, titanium dioxide will be banned completely in 2020. And though the European Chemicals Agency (EXHA) joined the World Health Organization and US agencies in declaring TiO2 suspected carcinogen, the EU has decided against issuing a health warning for the time being.


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Until next time!

CDA Oasis Team



  1. Vasant Ramlaggan July 9, 2019

    Thank you for the great written synopsis. I much prefer this to the video only interviews on topics such as this (I like the video accompanied by text ones better than just video.) As we all have very busy days, it’s great to be able to run quickly through the text to get to the point.

    Thanks again!

    1. CDA Oasis July 10, 2019

      You are most welcome Vasant and thank you for the great feedback 🙂

  2. Cliff Leachman July 10, 2019

    Gee Whiz, Who Knew?
    Guess blowing it into the lungs with the Cerec spray wasn’t such a great idea after all?
    Wait till the class action lawsuits begin for the early Cerec adopters.
    It’s not like we were not warned by many of us.

  3. Masimo July 11, 2019



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