Nanotechnology is now commonplace in the food industry. Nanoparticles, measured in nanometers (or billionths of a meter) are fragments of substances that behave very differently at a tiny scale than they do in their normal, or macro, form. They are hundreds of times smaller than a red blood cell. That means they can go places in the body, and interact with cells, in different ways than do unprocessed foods.
Substantial evidence links nanoparticles with “leaky gut,” numerous autoimmune diseases, and other adverse health effects.
Nanoparticles are used for a variety of purposes in food processing and packaging. They can be used to purify water, to prevent caking in powdered substances, to form gelatin, to protect against UV light in packaging, to prevent the growth of bacteria, and to detect contamination.
One of the most commonly used nanoparticles is titanium dioxide (TiO2). This is used in toothpaste (to make it look whiter), sunscreen, and cosmetics. It is also used in many processed foods including mints, gum, coated candies, vitamins, frosting, pudding, creamers, cheese substitutes, and other items. Most Americans consume at least some TiO2 every day.
Health effects: Because nanoparticles can penetrate the body in ways that naturally occurring substances cannot, they interact with it and affect it in unintended ways. Known health effects of nanoparticles include:
- Systemic genetic damage in mice, including single- and double-strand DNA breaks, chromosomal damage, and inflammation, all of which increase the risk for cancer.
- Pathological lesions in the liver, spleen, kidneys, and brain, when introduced into the body through the lungs or gastrointestinal tracts.
- Diseases associated with inhaled nanoparticles include asthma, bronchitis, emphysema, lung cancer, Parkinson’s and Alzheimer’s.
- Nanoparticles in the gastrointestinal tract are linked to Crohn’s disease and colon cancer.
- Nanoparticles that enter the circulatory system are implicated in arteriosclerosis, blood clots, arrhythmia, and heart disease.
- In human cells as well as in the lungs of mice, nanoparticles have been found to transform the amino acid arginine into a molecule called citrulline. Citrulline is indicated in the development of autoimmune diseases, such as rheumatoid arthritis, lupus, and scleroderma.
Autoimmune disorders: The role of nanoparticles in the development of autoimmune diseases is particularly disturbing, and the mechanism is quite clear. The conversion of the amino acid arginine into citrulline causes human proteins that use this modified building block to become dysfunctional. The immune system targets these faulty (citrullinated) proteins and attacks its own tissues and organs, into which the faulty proteins are incorporated.
Leaky gut: Nanoparticles and other industrial food additives are also implicated in the development of “leaky gut,” or tight junction dysfunction. The tight junction (TJ) is comprised of a complex network of plaque proteins. This thin layer is responsible for preventing intestinal permeability. If the TJ stops working properly, the immune cells in the lamina propria (below the epithelium) will be exposed to a huge number of foreign antigens, causing an overreaction of the immune cells known as the autoimmune cascade.
Diet plays a critical role in determining the development of leaky gut. Emulsifiers, organic solvents, microbial transglutaminase, and nanoparticles have all been shown to increase intestinal permeability by breaching the integrity of the tight junction. Some beneficial bacteria and probiotic strains can help reverse intestinal permeability, strengthening the tight junction.
Transglutaminase: Nanoparticles are used in the production of microbial transglutaminase (mTG), an enzyme widely used in food processing. Transglutaminase is an enzyme that helps proteins bond. Its cross-linking property is used to manufacture cheese, baked goods, and in meat processing (it is sometimes known as “meat glue”). It is used to increase the firmness, viscosity, elasticity and water-binding capacity of processed foods.
Because mTG makes proteins more stable, it makes them harder for the body to eliminate. It has also been found to increase intestinal permeability. This combination exposes gluten proteins (gliadens) in greater quantities to the immune cells in the epithelium, possibly helping to trigger celiac disease.
Additionally, the presence of antibodies to transglutaminase is a key diagnostic indicator of celiac disease, suggesting that the presence of unlabeled mTG in the food supply is not doing celiacs any favors.
In summary, the rise of industrial food additives such as nanoparticles and transglutaminase is probably not coincidental to the rise of autoimmune disorders. Better labeling is needed to make it possible for consumers to determine whether to avoid such ingredients.
For further reading:
Kieliszek, M., & Misiewicz, A. (2014). Microbial transglutaminase and its application in the food industry. A review. Folia Microbiologica, 59(3), 241–250. http://doi.org/10.1007/s12223-013-0287-x
Lerner, A., and T. Matthias. (2015). Food Industrial Microbial Transglutaminase in Celiac Disease: Treat or Trick. International Journal of Celiac Disease, 3(1): 1-6. doi: 10.12691/ijcd-3-1-10
Lerner, A., and T. Matthias. (2005). Changes in intestinal tight junction permeability associated with industrial food additives explain the rising incidence of autoimmune disease. Autoimmune Review, 14(6): 479-89. doi:10.1016/j.autrev.2015.01.009.
Liu, Z., N. Li, and J. Neu. (2005). Tight junctions, leaky intestines, and pediatric diseases. Acta Paediatr 94(4): 386-93.
Mohamed, B.M., et al. (2012). Citrullination of proteins: a common post-translational modification pathway induced by different nanoparticles in vitro and in vivo. Nanomedicine 7(8): 1181-1195. doi:10.2217/nnm.11.177
Shi, H., R. Magaye, V. Castranova, and J. Zhao. (2013). Titanium dioxide nanoparticles: a review of current toxicological data. Particle and Fibre Toxicology 201310:15. doi: 10.1186/1743-8977-10-15
Ulluwishewa, D., et al. (2011). Regulation of Tight Junction Permeability by Intestinal Bacteria and Dietary Components. The Journal of Nutrition March 2011. doi: 10.3945/jn.110.135657.