New research sheds light on a possible cause of autism: processed foods

The more we learn about the microbiome, the more the pieces are fitting together.

New research sheds light on a possible cause of autism: processed foods

Florida, Sanibel Island, Jerry's Foods, supermarket Cereal Aisle.

Photo: Jeffrey Greenberg/Universal Images Group via Getty Images
  • A new study from the University of Central Florida makes the case for the emerging connection of autism and the human microbiome.
  • High levels of Propionic Acid (PPA), used in processed foods to extend shelf life, reduces neuronal development in fetal brains.
  • While more research is needed, this is another step in fully understanding the consequences of poor nutrition.


A new study from the University of Central Florida, published in Scientific Reports on June 19, makes the case for the emerging connection of autism and the human microbiome. High levels of Propionic Acid (PPA), which is used in processed foods to extend shelf life and inhibit the growth of mold, appears to reduce neuronal development in fetal brains.

Turning to diet to better understand autism is not new. This new study implicates the mother's diet in the onset of autism in the developing fetus. Such a finding, if proven true, could have important consequences for prenatal care moving forward.

As the team comprised of Latifa S. Abdelli, Aseela Samsam, and Saleh A. Naser writes, autism spectrum disorder (ASD) is marked by neuro-inflammation and gastrointestinal symptoms. The spectrum includes varying levels of impaired social communication, as well as repetitive behaviors that impede a child's learning progress and ability to relate to others.

The number of children diagnosed with ASD has been ticking up by the year, though as Silberman writes, the spectrum is not new. Still, something is changing in societies causing this surge. In 2000, the CDC observed one out of every 150 children exhibiting such behaviors; by 2018, that number climbed to one of out every 59.

Could Autism Be Caused by Gut Microbes? | Dr. Emeran Mayer

The research team notes that thousands of genes are associated with ASD. While there is no singular likely culprit — they believe it is an interplay between genetic and environmental forces — they focused on maternal immune system abnormalities. Naser, who specializes in gastroenterology research, homed in on PPA as he had previously observed high levels of this carboxylic acid in stool samples of children with autism.

Excessive PPA reduces the number of neurons in the brain while simultaneously overproducing glial cells, resulting in inflammation, a marker of autism. Increased amounts of PPA damage neuronal pathways that allow the brain to communicate with the body. This toxic cocktail matches the symptoms of autism: repetitive behaviors, mobility issues, trouble communicating with others.

PPA naturally occurs in the human microbiome. Increased amounts of the acid, consumed by mothers by way of processed foods, appears to have a negative effect on their children. Increased PPA crosses into the fetus, potentially stunting neuronal development, which could aid in triggering the cascading effects that lead to the spectrum.

The acid was first discovered in 1844 by Austrian chemist, Johann Gottlieb, who noticed it in degraded sugar products. Isolated, it gives off the scent of unpleasant body odor. Manufactured, however, it is used to stop molding in animal feed, as well as human food products, including grains, baked goods, and cheese. It is approved for usage in the EU, USA, Australia, and New Zealand.

Autistic child attends the World Autism Awareness Day 2019 celebrations on April 2, 2019 in Kuala Lumpur, Malaysia. Photo credit: Mohd Samsul Mohd Said / Getty Images

Previous research has linked too much PPA with everything from nose and throat irritation to birth defects and cancer (in rats). While it is generally considered low in toxicity if swallowed, this study from UCF suggests that its effects on the maternal microbiome is far greater than previously imagined. It is, according to the researchers, only a first step, but an important one:

"This research is only the first step towards better understanding of Autism Spectrum Disorder. But we have confidence we are on the right track to finally uncovering autism etiology."

There is no benefit without cost. The low health cost of vaccines, for example — some injuries compared to untold millions of lives saved — seems a worthwhile tradeoff.

The high cost of processed foods does not seem to be worth the tradeoff, however. Convenience food is a market creation, not an evolution in good nutrition. Bread should not last for weeks on a shelf. Animals should not be fattened with low-nutrition foodstuffs, especially if the chemistry involved in producing it is ultimately harming our species.

These are the real costs of our agricultural system, which is having a direct, negative impact on our microbiomes. The research might not provide the answers that we're predisposed to believing, but science is not about popularity of responses. PPA might not be the cause of autism, and this research requires follow-up studies, but still, it's pointing to one potentially important marker.

--

Stay in touch with Derek on Twitter and Facebook.

New study cautions marijuana beginners to 26 adverse reactions

Researchers documented the most common negative side effects of smoking weed, and who might be most susceptible.

Surprising Science
  • A team of researchers identified a total of 26 possible adverse reactions to cannabis use.
  • Coughing fits, anxiety, and paranoia are among the top three most common adverse reactions to smoking weed.
  • It was the people who smoke on a less frequent basis who were more likely to have had the bad experiences.
Keep reading Show less

Coffee and green tea may lower death risk for some adults

Tea and coffee have known health benefits, but now we know they can work together.


Credit: NIKOLAY OSMACHKO from Pexels
Surprising Science
  • A new study finds drinking large amounts of coffee and tea lowers the risk of death in some adults by nearly two thirds.
  • This is the first study to suggest the known benefits of these drinks are additive.
  • The findings are great, but only directly apply to certain people.
Keep reading Show less

Why San Francisco felt like the set of a sci-fi flick

But most city dwellers weren't seeing the science — they were seeing something out of Blade Runner.

Brittany Hosea-Small / AFP / Getty Images
Surprising Science

On Sept. 9, many West Coast residents looked out their windows and witnessed a post-apocalyptic landscape: silhouetted cars, buildings and people bathed in an overpowering orange light that looked like a jacked-up sunset.

Keep reading Show less
Strange Maps

Finland is the 'most sustainable' country, say expats

India finishes last of 60 countries in environment and sustainability, as ranked by the expats who work there.

Scroll down to load more…
Quantcast