Nanoparticles in food What happens during digestion?

Nanoparticles in food: is that bad for our health

Foods can contain nanoparticles that enhance the product properties as additives. For example, particles of silicon dioxide may be stuck in instant soups to prevent the soup from clumping. Tiny titanium dioxide particles make chewing gum and yoghurt dressing shine in a bright white.

Food additives are tested for their health safety prior to authorization. Manufacturers are required to label all ingredients in the form of "engineered nanomaterials" on the "Nano" label. "Nano" means the billionth part of one meter (= 1 nanometer). However, according to the Federal Association of Consumer Centers e. V. (vzbv) so far practically no conventional ingredients that fall under this definition. Natural, random or process-related nanomaterials are not subject to labeling. These include, for example, particles that are formed when grinding flour, brewing beer or when homogenizing fruit juices.

But how do nanoparticles in food affect our stomach and intestinal flora? Scientists from the Center for Medical Biotechnology at the University of Duisburg-Essen have been dealing with this question. To do this, they simulated the passage of tiny particles through the body in the laboratory. Nanoparticles encounter very different conditions on their way through the digestive tract - from saliva to the acidic environment in the stomach and the more "neutral" intestine.

Apparently, a large number of nanoparticles can bind to harmful and beneficial bacteria, including probiotic germs. This applies to artificial and natural nanoparticles that scientists have isolated from beer. The effects were positive and negative, microbiologists explain in the journal Nature Publishing Journal - Science of Food. Thus, the immune system can recognize pathogenic bacteria worse when they are covered with nanoparticles. This favors inflammatory processes in the intestine. On the other hand, according to the experts, Silicea nanoparticles weaken the infectivity of the seed Helicobacter pylori, which is significantly involved in the development of gastric cancer. There is still a lot of research needed in the field of nanotechnology. The current results should help to better understand the biological mechanisms in the digestive tract and to further develop the use of nanoparticles in food. Heike Kreutz, bzfe