How we’re exposed to an ingredient matters greatly in terms of our long-term health. 
  
Research shows that inhaling titanium dioxide particles in significant quantities over time can cause adverse health outcomes. Unless you work in an industrial setting, inhaling substantial amounts of titanium dioxide is highly unlikely. 

In a small study published in the European Journal of Nutrition in 2020, researchers examined the effects of several food additives, including titanium dioxide, along with artificial sweeteners and cleaning products by testing the fecal samples of 13 people. Titanium dioxide was among the samples that “induced significant shifts in microbiome community structure.”  The growth of the bacterium species belonging to C. leptum, which has been shown to decrease in patients with inflammatory bowel disease, “significantly decreased in the presence of … titanium dioxide” among other additives and sweeteners tested.

In response to the allegations, Justin Comes, vice president of research and development at Mars Wrigley North America, told Health that safety is of paramount importance to Mars Wrigley. While we do not comment on pending litigation, all Mars Wrigley ingredients are safe and manufactured in compliance with strict quality and safety requirements established by food safety regulators, including the FDA.

Australian researchers examined how titanium dioxide as a food additive affected gut microbiota in mice by orally administering it in drinking water. The study, published in the journal Frontiers in Nutrition in 2019, found the 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 titanium dioxide significantly impacts gut homeostasis.” The changes were then linked to colonic inflammation, along with a higher expression of inflammatory cytokines, which are signal proteins that help with regulation. The researchers concluded that titanium dioxide “impairs gut homeostasis which may in turn prime the host for disease development.”

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