titanium dioxide is prepared from manufacturers

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Titanium dioxide helps protect the skin from both UVA and UVB rays. Plus, it’s generally considered to be safe for sensitive skin types. Not only that, but it might also make for sunscreens that are more suitable for children and infants since it’s much less likely to cause stinging compared to chemical sunscreens. And when used in foundations, titanium dioxide can even provide a little extra sun protection on top of your daily SPF.

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In a study published in the journal Food and Chemical Toxicology in 2016, researchers investigated whether titanium dioxide exposure led to an increase in colorectal tumor creation in mice by using a colitis associated cancer model. By measuring tumor progression markers, the researchers found that mice given titanium dioxide experienced enhanced tumor formation in the distal colon.  There was also a decrease of cells that act as a protective barrier in the colon. The researchers wrote: “These results suggest that E171 could worsen pre-existent intestinal diseases.”

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The disadvantage of Titanium Dioxide is that it's not cosmetically elegant, meaning it's a white, unspreadable mess. Sunscreens containing Titanium Dioxide are often hard to spread on the skin and they leave a disturbing whitish tint. The cosmetic industry is, of course, really trying to solve this problem and the best solution so far is using nanoparticles. The itsy-bitsy Nano-sized particles improve both spreadability and reduce the whitish tint a lot, but unfortunately, it also introduces new health concerns. 

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