Love Fried Foods? Feeling Anxious?

"Here we revealed that fried food consumption, especially fried potato consumption, is strongly associated with a higher risk of anxiety and depression symptoms."

"Western dietary patterns have been unfavourably linked with mental health."

"However, the long-term effects of habitual fried food consumption on anxiety and depression and underlying mechanisms remain unclear."

Study Researchers, Hangzhou, China 

"[The research] irritates me in many ways. To suggest that there is one single cause of depression is absolute nonsense."

"[A very legitimate study was used to collect data] and then the researchers take this data and they analyze it to see what they can squeeze out of it."

"The takeaway is that if you raise zebra fish, don't let them swim in acrylamide-laced water."

McGill University chemistry Professor Joe Schwarcz

"It's an interesting study, but it doesn't change what was already known -- that a diet based on plenty of vegetables, fruit, nuts, seeds, pulses and moderate amounts of other foods is associated with better mental and physical health."

"Caution should be used when using animal models which only show 'anxiety-like' symptoms."

"[Toasted bread and coffee are also significant sources of acrylamide]."

Dr. Duane Mellor, senior lecturer, registered dietitian, Aston University, Birmingham, England 

"I've worked in a hospital setting for over a decade  helping people who experience severe depression."

"French fries don't land people in hospital."

Professor Jonathan Stea, clinical psychologist, University of Calgary adjunct assistant professor

Go ahead, eat that french fry. Photo by Getty Images

It isn't entirely unusual for research papers to be published, as was this study that saw publication in peer-reviewed journal, PNAS (the Proceedings of the National Academy of Sciences) conducted by researchers from Hangzhou, China, whose results face criticism. Where 140,728 subjects who took part in  he U.K. Biobank, a biomedical database and research resource replete with genetic, health and lifestyle information from a half-million U.K. participants, which gained critical and often controversial rebuttals from other scientists.

 

And this study seemed to hit all the right buttons for unfavourable feedback in its contention that the study concludes with that consumption of too many fried foods could lead to depression. "It may be that depressed people are more likely to eat French fries as a comfort food", responded Dr. Joel Shulkin. Yet this is a widely circulated study purporting to reveal that those who consume a plenitude of French fires face a higher risk of anxiety and depression.

 

Males, according to the study results, were seen to be particularly susceptible. The working hypothesis of the study is that enthusiasts of fried foods are exposed to acrylamide, a chemical which forms through a chemical reaction when plant-based and other foods are fried, roasted or baked, and most particularly at high temperatures. During frying, amino acids and sugars in the food react, giving foods a toasty crust and flavour -- the entire point of the process -- that appeals to the human palate.

 

The researchers focused on whether an association between frequent fried food ingestion and depression existed. Their study first looked at humans, then zebra fish. Biobank humans were followed for an average of 11 years. Those who reported eating more than one serving a day of fried foods had a 12 percent higher risk of anxiety and a seven percent higher risk of depression, compared to those who did not indulge.

 

The browner the surface of the food being fried, the higher the level of acrylamide will be present.  It is not entirely clear what risk acrylamide poses to humans, according to the U.S. Food and Drug Administration. However, it is classified as "likely to be carcinogenic to humans", by the U.S. Environmental Protection Agency.

The Chinese study authors in another, separate study reported long-term exposure to acrylamide led to anxiety-and depressive-like behaviours in adult zebra fish. Exposure made the fish less sociable, spending more time in dark zones and more time at the bottom of the tank, an indication of anxiety. The researchers identified symptoms of oxidative stress, a condition caused by an overabundance of tissue-damaging free radicals, along with cerebral inflammation in the fish.

The study subjects who consumed fried foods were likelier to be smokers, to have a higher body mass index and lower income and education levels: "Factors that are likely affecting mental health and that cannot be completely excluded in the analysis", stated Gunger Kihnie, professor of nutrition and food science at University of Reading.

According to Professor Schwarcz, it is possible that acrylamide is neurotoxic, since anything causing inflammation can affect all cells, including neurons. In view of cancer risks, people should reduce their intake of acrylamide. The level present in fries, suggests the professor, can be reduced by soaking the potatoes first in water, draining, then frying.

French Fries   Getty Images