Proteins in food can trigger an allergic reaction in certain people. However, if the child’s immune system or intestinal barrier is impaired, they may become sensitive and suffer an allergic reaction to foods that they would normally build oral tolerance to.
Two to five percent of adults and six to eight percent of children suffer from food allergies, and this number has risen dramatically over the past few decades. Although environmental factors are well-known to play a role in allergy development, the higher frequency in children shows that environmental influences throughout early life are likely crucial. The development of oral tolerance can be hampered if infants and toddlers aren’t exposed to a variety of foods and aren’t given enough of certain nutrients, such as a diverse gut bacteria and dietary proteins.
New methods of food production, manufacturing, and processing made possible by nanotechnologies have the potential to significantly improve the quality and safety of the food we eat. Such a radical shift in food production may have unintended repercussions for human health, as Mohammad Issa of the Université Paris-Saclay and his colleagues noted in a review article published in Frontiers in Allergy. The group showed evidence that nanoparticles can pass the placenta and pose a danger of life-threatening food allergies to growing fetuses.
In order to learn how nanoparticles can upset this delicate equilibrium, the scientists zeroed in on three chemicals commonly used in food that include nanoparticles.
Although it has been shown that nanoparticles can pass the placenta in rats, there is also evidence that the additives can do so in humans. Nanoparticles are too large to be digested by the digestive system, so they build up in the gut instead, where they alter the composition of the microbiome by altering the number and abundance of different bacterial species. This is worrisome for allergy development given the evidence supporting the role of the gut microbiota in the formation of a mature immune system. The intestinal epithelium is also affected by nanoparticles, which is a bummer because it plays a crucial role in how your body responds to the proteins in your diet.
While proof of immunotoxicity is more difficult to come by, the team did present data suggesting that these nanoparticles have deleterious effects on human gut-associated lymphoid tissue. Consistent with findings from research in rodents, this suggests a much larger impact on the immune system than is currently appreciated. In most cases, however, these indicate a significantly greater dose than what is believed to be consumed by humans.