Nanoparticles in Food

There's a team of researchers at my undergraduate alma mater who are working on the effects of nanoparticles. This is the second time I've seen an article on their research in my alumni magazine; the first time I meant to post about it, but it never happened. In a way, it's just another thing to worry about that's beyond your control, but still. Better informed than in the dark.

Here's the more recent article:

Need another reason to cut back on processed food? [This] research finds that the ability of small intestine cells to absorb nutrients and act as a barrier to pathogens is significantly decreased after chronic exposure to nanoparticles of titanium dioxide, a common food additive found in everything from chewing gum to bread.

Chronic exposure—defined as the amount of titanium dioxide that could be present in three meals over five days—diminished the absorptive projections on the surface of intestinal cells, called microvilli. With fewer microvilli, the intestinal barrier is weakened, metabolism is slowed and some nutrients—iron, zinc and fatty acids, especially—were difficult to absorb. Enzyme functions were negatively affected, while inflammation signs increased.

"Titanium oxide is a common food additive, and people have been eating a lot of it for a long time. Don't worry, it won't kill you! But we were interested in some of the subtle effects, and we think people should know about them," said [the one of the authors]. "To avoid foods rich in titanium oxide nanoparticles you should avoid processed foods, and especially candy. That is where you see a lot of nanoparticles."

A press release I found online says that titanium dioxide is a white pigmentation used in paints and papers, plus sunscreen and toothpaste (it's also an abrasive). It's found in chocolate (where it makes for a smoother texture... wait, I thought it was abrasive?). It's added to skim milk (!) to make it whiter and more opaque.

That press release contained this gem:

A 2012 Arizona State University study tested 89 common food products including gum, Twinkies, and mayonnaise and found that they all contained titanium dioxide. About five percent of products in that study contained titanium dioxide as nanoparticles. Dunkin Donuts stopped using powdered sugar with titanium dioxide nanoparticles in 2015 in response to pressure from the advocacy group As You Sow.

Grrrrrrreat! Thanks, university!