It seems like food manufacturers and scientists are trying to make food less and less real and more and more alien and unhealthy. First there was homogenization and pasteurization, then the addition of artificial colors, flavors, and preservatives, and next came genetically modified organisms (GMOs). Now we have nanoparticles.

Nanoparticles are ultramicroscopic additives that are usually added to foods to make them look more appealing and to avoid discoloration. Not only do these additives not contribute any nutritional value, they are so small they can infiltrate the bloodstream and thus reach all parts of the body, where they have the potential to cause damage.

In the majority of cases, nanoparticles used in food are composed of titanium dioxide, which has a dubious health record, even though the Food and Drug Administration has classified it as Generally Recognized as Safe (GRAS). In fact, titanium dioxide is widely used in sunscreen because it helps reflect ultraviolet light. Unless you are exposed to internal sunshine, do you need to ingest titanium dioxide?

What some research shows

The findings of a new (December 2016) study in Nanotoxicology, conducted by a team in The Netherlands, found evidence that oral exposure to nanoparticles of titanium dioxide could have negative effects on the liver, ovaries and testes over time. This is especially relevant when it comes to children, who may be more vulnerable to potential dangers from nanoparticles. A report in Environmental Science & Technology pointed out that an analysis of human exposure to titanium dioxide in foods “identified children as having the highest exposures because TiO2 content of sweets is higher than other food products.”

According to Georgios Pyrgiotakis, PhD, of the Harvard School of Public Health, nanoparticles could pass into the bloodstream, where they could cause inflammation as well as accumulate in the body and disrupt normal biochemical processes. The International Agency for Research on Cancer classified titanium dioxide as being “possibly carcinogenic to humans.”

Experts warn about nanoparticles in food

Research in animals suggests that nanoparticles in food can cause inflammation of the digestive tract, destroy DNA, and damage cells. Although these studies used amounts of nanoparticles greater than those present in human foods, there is the cumulative factor to consider in people who continue to consume products that contain these minute substances. Foods that contain the greatest amount of titanium dioxide nanoparticles include candies, chewing gum, and other sweets, such as powdered doughnuts, which are bright white because of titanium. You may also encounter them in coffee creamers, mayonnaise, pudding and some dairy products.

Another reason to worry about health dangers associated with nanoparticles is the lack of adequate testing of their safety. Since the practice is relatively new, we don’t yet have enough scientific evidence to prove the extent of potential damage caused to human health by adding nanoparticles to food. One this is for certain: such testing should be conducted by unbiased parties and not by food manufacturers.

Yet more challenges facing scientists who are exploring the question of safety of nanoparticles in food include the fact that “the difference between humans and laboratory animals prevents extrapolation of the results,” as noted by experts in the Journal of Nanoparticle Research. In addition, investigators don’t have the proper tools to conduct accurate testing of nanoparticles.

Experts note that “improvements in at least three domains” are necessary to better understand the risks: One, accurate testing methods need to be developed that can address the unique properties of nanomaterials, as “conventional methods cannot be used in their case.” Two, there’s a lack of “systematic classification” of nanomaterials, which hinders proper research; and three, scientists must develop adequate models for assessing toxicity of nanoparticles in foods.

It seems clear that the safety of nanoparticles in our food supply is an unknown and that the public is thus a guinea pig in the midst of uncertainty. What we don’t know or understand can harm us, and that would seem to be the case for dietary nanoparticles.