Are Nanoparticles in Supplement Beverages Harmful?

Nanotechnology is often hailed as the tomorrow of functional foods and beverages. Through nanotechnology, formulators have the potential to deliver nutrients to consumers in new and often more bioavailable ways-for instance, by encapsulating hydrophobic ingredient molecules. However, much is still unknown about nanotechnology, including whether or not these nanoscale particles in fact pose risks because they can go where no particles have gone before. (For more on the risks, read this article.) 

Through a grant from the National Science Foundation, researchers conducted an in vitro study to determine how nanoparticles might affect the digestive system post-consumption. “Little information is available regarding the suitability of analytical methods to evaluate claims regarding the presence of engineered nanomaterials (NMs) in consumer products, their potential toxic effects to humans, or their life cycle after product use. This study was designed to assess the potential interactions across the life cycle of eight commercially available dietary supplement drinks from a single vendor, all purported to contain metal NMs,” the researchers stated.

The researchers ran tests on eight dietary supplement drinks from a company called Purest Colloids Inc., whose products contain colloidal silver or other colloidal metals. On its website, Purest Colloids states, “While we make no health claims about the use or effectiveness of silver colloidal or our product line, our customers have found colloidal silver and many of our other products helpful in a wide variety of applications,” including immune system support, stress relief, and improved sports performance. Also, it states, “Our colloids provide the body with minerals to maintain optimum health. By maximizing the particle surface area of the nanometer-sized particles, we keep our products in the forefront of quality and effectiveness.”

In the study published in the American Chemical Society’s journal ACS Sustainable Chemistry & Engineering, researchers said they found that the metal nanoparticles, once consumed, may effectively decrease the number of microvilli in the small intestine. (Microvilli are the finger-like protrusions on the wall of the small intestine that aid in nutrient absorption.)

“Together, these data indicate the need to investigate further in vivo effects in models that accurately emulate the human gut, since a loss in the number of microvilli could result in pathological states such as malabsorption or diarrhea,” they wrote.

“To the best of our knowledge, the present study is the first to report characterization of metal NM-enabled dietary supplement drinks mean to be directly ingested,” they added.

Food and drink isn’t the only way we interact with nanoparticles. Nanotechnology is also used in packaging to increase tensile strength and to control gas permeability, as well as for antimicrobial purposes. Researchers are also looking at the environmental impact of nanoparticles-for instance, on wastewater-management systems, as nanoparticles pass from human waste to the environment.

Jennifer Grebow
Editor-in-Chief
Nutritional Outlook magazine jennifer.grebow@ubm.com