Chemical Additives in Processed Food Cross the Placenta, Damage Babies’ Immune System, say scientists

A new warning from scientists about food additives: Billions of nanoparticle food additives can reach infants, even crossing the placenta during pregnancy. These chemical food additives can change the baby’s gut microbiome and damage gut cells. This phenomenon, researchers believe, likely raises allergy and immune disorder risk.

Medical reports of child allergies have been on the rise for the past twenty years in both the U.S. and the UK. One culprit may be the chemical additives–especially nanoparticles like titanium dioxide–common in processed foods.

It has been demonstrated that tiny particles added to sugars, sweeteners and preservatives used to make sweets, cakes,  syrups and other processed foods can cross the placenta and reach the fetus. Once this occurs, the nanoparticles accumulate in the gut and disrupt babies’ microbiome.

Study overview

Scientists base their assessment on their analyses of over 170 scientific studies on the topic, including studies carried out in the lab, in animal studies and in human trials. The researchers focused on three additives found in many processed foods — including titanium dioxide, which is commonly used for texture and white coloring in dairy products, candies, salad dressing and chewing gum. The study also looked at the commonly used emulsifier silicon dioxide, which stops foods from caking or sticking together, and the preservative nanosilver, used in food packaging to extend the shelf-life of snacks.

The results demonstrated numerous scientific studies that showed the presence of these nanoparticle food additives common in processed foods with disruption in the guts of newborns.  The gut does not absorb the tiny particles; instead, they clump together and disrupt the surrounding bacteria. Because the microbiome is so connected to the immune system, the researchers theorize it could be playing a role in the development of allergies.


Over 900 food products include at least one additive or component that is defined as a nanoparticle. The most common sub-sectors are infant formula (26 percent), confectionery (16 percent), breakfast cereals (15 percent), cereal bars (13 percent) and frozen pastries and desserts (11 percent).  Women who are pregnant and those who are breastfeeding may want to consider avoiding processed foods that contain nanoparticles.  In the U.S., foods may not list nanoparticles on the ingredients labels, so it is wise to avoid or severely limit processed foods (especially highly processed foods) all together and make your own meals, drinks and snacks using fresh, whole ingredients, organic where possible.

Journal reference: Issa, M., Riviere, G., Houdeau, E. & Adel-Patient, K. Perinatal exposure to foodborne inorganic nanoparticles: A role in the susceptibility to food allergy? Frontiers in Allergy, 05 December 2022 Sec. Food Allergy | overview| Study: