Versus home-cooked meals, eating out piles on the toxins called PFAS
Home cooking typically features whole foods rather than processed fare.
That matters, given the growing evidence that whole foods are much healthier than packaged and takeout products.
Sadly, a recent analysis of data from the National Health and Nutrition Examination Survey 2007-2012 found that the average American gets about 57% of their calories from “ultra-processed” foods and drinks (Baraldi LG et al 2018).
Ultra-processed foods and drinks share common features: they result from several industrial processes, contain additives designed to mimic natural foods or disguise unpalatable tastes, contain few or no intact whole foods, and are ready to drink, eat, or heat up.
Unsurprisingly, many fast foods and takeout foods fall into the ultra-processed category, and diets high in them are increasingly linked to obesity, diabetes, and heart disease.
Now, new research reveals another good reason to favor home-cooked foods, which is the finding that takeout and fast foods — and people who eat them routinely — frequently contain harmful chemicals called PFAS.
What are PFAS?
PFAS is the acronym for per- and polyfluoroalkyl substances.
This huge group of manmade chemicals — widely manufactured and used since the 1940s, and numbering about 5,000 — includes PFOA and PFOS, which have been the most extensively produced and studied.
Unfortunately, PFAS persist for decades and accumulate in the environment and our bodies, where they can cause or help promote adverse health conditions.
Under pressure from the EPA, all U.S. manufacturers of PFAS had stopped making traditional “long-chain” PFOA and PFOS by 2015. But they’ve replaced them with “short-chain” PFAS, such as GenX, which are about equally persistent and may — judging by emerging evidence — raise similar health concerns.
And long-chain PFOA and PFOS are still entering the country as constituents of imported plastics, packaging, carpet, leather, clothing, textiles, paper (including paper plates and cups), coatings, rubber, and non-stick, stain-resistant, or waterproof products.
According to the American Cancer Society, non-stick cookware coatings aren’t considered a significant source of PFAS, which get “burned off” during the manufacturing process. However, experts still advise people to avoid non-stick cookware, and use well-seasoned iron pans instead.
Because PFAS have been accumulating in the environment since the 1940s, they've been detected in soil, water (see "Alarming levels of PFAS", below), food crops, meats, dairy, and fish, prompting scientists to study the possible health risks.
Lawsuits brought against DuPont forced the chemical company to admit it had contaminated water supplies with PFAS, which it knew were dangerous. To date, people sickened by PFAS have been awarded more than one billion dollars in damages. (A movie based on the story of those lawsuits, titled “Dark Waters”, is due in November of 2019.)
How dangerous are PFAS?
There's no doubt that PFAS-type chemicals are toxic.
But much research on the range and character of the adverse effects of PFAS chemicals remains to be done.
We know that PFOA and PFOS can cause health problems in animals, including tumors of the liver, testicles, breast, and pancreas, as well as adverse reproductive, developmental, liver, kidney, and immunological effects.
As to people, there’s some evidence that PFOA and PFOS can raise cholesterol levels and cause low infant birth weights, adverse immune system effects, cancer (PFOA), and thyroid-hormone disruption (PFOS).
But the evidence collected to date paints a mixed picture. Some population studies link PFAS to immune-related problems — including cancers, allergies, infectious diseases, and chronic inflammatory or autoimmune conditions — while others don’t.
However, there’s more than enough worrying evidence from laboratory and human studies to warrant conscientious avoidance of these chemicals — especially among children and expectant mothers.
New PFAS study fingers takeout foods
Scientists at the Silent Spring Institute just delivered some concerning news about takeout foods and PFAS.
They analyzed data from 10,106 participants in the National Health and Nutrition Examination Survey (NHANES) which the Centers for Disease Control and Prevention (CDC) uses to track health and nutritional trends in the United States.
The participants were asked to recall, in detail, what they ate over the previous 24 hours, 7 days, 30 days, and 12 months, and they provided blood samples that were tested for the presence of several different PFAS.
And the analysis of NHANES data by SSI scientists showed that people who ate more meals at home had significantly lower levels of PFAS in their bodies. Unsurprisingly, the vast majority (90%) of these home meals featured foods purchased at a grocery store.
In contrast, people who consumed more fast food or ate more frequently at restaurants — including pizza places — tended to have higher levels of PFAS in their bodies, probably because takeout foods have more contact with PFAS-containing packaging.
“This is the first study to observe a link between different sources of food and PFAS exposures in the U.S. population,” said environmental chemist and study co-author Laurel Schaider, Ph.D. “Our results suggest migration of PFAS chemicals from food packaging into food can be an important source of exposure to these chemicals.”
The SSI team’s findings fit with those of previous research, including an earlier study by Silent Spring, which showed that PFAS are common in fast food packaging.
As in previous studies, the SSI researchers also found that people who ate more microwave popcorn had significantly higher levels of PFAS, which have previously been found in microwave popcorn bags.
It’s important to note that the SSI team’s analysis only included results for long-chain PFAS, because they were the most frequently detected — probably because U.S. manufacturers have been replacing long-chain PFAS with newer, supposedly safer short-chain varieties.
As study co-author Kathryn Rodgers noted, food packaging can contain other concerning chemicals, including hormone-disrupters such as BPA and phthalates. As she said, “These latest findings will hopefully help consumers avoid these exposures and spur manufacturers to develop safer food packaging materials.”
Alarming levels of PFAS in U.S. communities' drinking water
The Harvard team measured six types of PFAS in more than 36,000 drinking water samples collected by the EPA from 2013–2015.
In addition, they investigated areas around wastewater treatment plants, industrial sites that create or use PFAS, and training sites and airports that use fire-fighting foam containing PFAS.
They found PFAS in 194 out of 4,864 water supplies in 33 states across the U.S.
The worst-affected states, in order of highest to lowest PFAS levels, were California, New Jersey, North Carolina, Alabama, Florida, Pennsylvania, Ohio, New York, Georgia, Minnesota, Arizona, Massachusetts, and Illinois.
The highest levels of PFAS were found in watersheds near industrial sites, military bases, and wastewater treatment plants.
In total, 66 public water supplies serving six million people had at least one water sample that measured at or above the EPA safety limit.
And, according to Harvard professor Elsie Sunderland, a senior author of the study, “... recent work suggests drinking water safety levels should be much lower than the provisional guidelines established by EPA.”
How safe is your water?
The EPA recommends contacting your local county health department, many of which prepare an annual water quality report.
If your local health department doesn’t have a report that covers PFAS, it’s possible to have your water tested by a state-certified lab.
For more information, call the Safe Drinking Water Hotline at 800-426-4791 or visit the EPA lab network online.
- American Cancer Society. Teflon and Perfluorooctanoic Acid (PFOA). Accessed at https://www.cancer.org/cancer/cancer-causes/teflon-and-perfluorooctanoic-acid-pfoa.html
- Baraldi LG, Martinez Steele E, Canella DS, Monteiro CA.Consumption of ultra-processed foods and associated sociodemographic factors in the USA between 2007 and 2012: evidence from a nationally representative cross-sectional study. BMJ Open. 2018 Mar 9;8(3):e020574. doi: 10.1136/bmjopen-2017-020574.
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- Innes KE, Wimsatt JH, Frisbee S, Ducatman AM. Inverse association of colorectal cancer prevalence to serum levels of perfluorooctane sulfonate (PFOS) and perfluorooctanoate (PFOA) in a large Appalachian population. BMC Cancer. 2014 Jan 27;14:45. doi: 10.1186/1471-2407-14-45.
- Silent Spring Institute (SSI). People who eat more meals at home have lower levels of harmful PFAS chemicals in their bodies. October 9, 2019. Accessed at https://silentspring.org/news/people-who-eat-more-meals-home-have-lower-levels-harmful-pfas-chemicals-their-bodies
- Susmann HP, Schaider LA, Rodgers KM, Rudel RA. Dietary Habits Related to Food Packaging and Population Exposure to PFASs. Environ Health Perspect. 2019 Oct;127(10):107003. doi: 10.1289/EHP4092. Epub 2019 Oct 9.
- U.S EPA. Basic Information on PFAS. Accessed at https://www.epa.gov/pfas/basic-information-pfas