Junk food fiends have more to worry about than a ballooning waistline.
Chemical preservatives and other additives found in many popular processed foods may be undermining snackers’ immune systems, according to a new study.
Two compounds, tert-butylhydroquinone (TBHQ) and per- or poly-fluoroalkyl substances (PFAS), have been identified in more than 1,200 foods sold in the US.
TBHQ, a preservative, can be found in well-known brand foods, including Kellogg’s Pop-Tarts, Rice Krispies Treats and Cheez-Its; PFAS — also known as “forever chemicals” because they survive indefinitely — are often used to create a non-stick lining in packaging, such as aluminum cans, pizza boxes and popcorn bags, and may leach into food contained within the package, according to the Environmental Working Group, whose findings were published in Journal of Environmental Research and Public Health on March 24.
Researchers for the EWG based their assessment on data compiled by the Environmental Protection Agency’s Toxicity Forecaster, a k a ToxCast. The data showed that TBHQ, which has been used to extend the shelf life of processed foods for decades, may impair the immune system, based on animal as well as in vitro (non-animal) testing.
In a statement, Dr. Olga Naidenko, EWG’s vice president for science investigations, suggested that poor diets may have contributed to the severity of the coronavirus outbreak.
“The pandemic has focused public and scientific attention on environmental factors that can impact the immune system,” said Naidenko, who led the study. “Before the pandemic, chemicals that may harm the immune system’s defense against infection or cancer did not receive sufficient attention from public health agencies. To protect public health, this must change.”
Previous studies have indicated that TBHQ could diminish the efficacy of flu vaccines, and may also promote food allergies. This could help explain why food allergy prevalence has increased by about 50% between 1997 and 2011, according to the US Centers for Disease Control and Prevention.
There have also been studies to suggest that PFAS suppresses immune function, including a report, published in Plos One last December, that found an association between people with high levels of these substances in the blood and increased COVID-19 severity. The results reflect that of a similar study in 2013, which determined that children who were exposed to high levels of PFAS in-utero produce fewer disease antibodies following pediatric vaccinations.
Of the more than 4,700 unique PFAS identified in manufacturing, very few have been studied for long-term health effects. In 2019, the EPA announced a research initiative to better understand PFAS following studies that linked them to cancer, thyroid disease, immune suppression, decreased fertility and low birth weight.
Study authors point out that animal and in vitro studies are not always consistent with human studies — as was the case with ToxCast’s data — and called for further research to learn more about how these chemicals interact with our immune system.
These findings are not yet evidence enough for the Food and Drug Administration to enact stricter limits; instead, the FDA continues to allow companies to self-determine whether the additives and preservatives used in their manufacturing are safe for long-term human health.
“Food manufacturers have no incentive to change their formulas,” said Scott Faber, senior vice president for government affairs at EWG. “Too often, the FDA allows the food and chemical industry to determine which ingredients are safe for consumption. Our research shows how important it is that the FDA take a second look at these ingredients and test all food chemicals for safety.”