High Amounts Of Salty, Processed Foods Could Double Stress Levels, Study Finds

A recent European study showed that excess salt consumption doubled the peak stress response in mice. Design by MNT: Photography by Benjamin Torode/Getty Images & Milko/Getty Images
  • While the physical effects of excess salt intake are well documented, scientists have yet to understand how high salt consumption impacts emotional well-being.
  • A recent European study showed that a salt-rich diet can double the peak stress response in mice.
  • Researchers are also looking into how high salt intake may induce anxiety and aggression.
  • They hope to see governments and food manufacturers collaborate to reduce salt in processed foods.

Salt is known to improve the taste of many foods, which may tempt consumers to buy more processed, salt-laden products. Common processed foods include commercially packaged bread, cereals, deli meats, soups, cheese, and instant noodles.

Increasing evidence shows that too much salt in the diet can wreak havoc on the body’s cardiovascular and renal systems. 

Recently, scientists at the University of Edinburgh in Scotland theorized that high salt consumption might also impose stress on the brain. The results from the experiment showed that high salt intake could elevate stress hormone production.

The study linked the consumption of large amounts of salt-rich food to the activation of the hypothalamic-pituitary-adrenal (HPA) axis, the body’s stress response system. The researchers also noticed a high-salt diet led to increases in glucocorticoids, naturally occurring hormones that help regulate stress response and cardiovascular, cognitive, immune, and metabolic functions.

Matthew Bailey, Ph.D., lead author of the study and professor of renal physiology at the University of Edinburgh’s Centre for Cardiovascular Science, told Medical News Today:

“We are what we eat, and understanding how high-salt food changes our mental health is an important step to improving well-being. We know that eating too much salt damages our heart, blood vessels, and kidneys. This study now tells us that high salt in our food also changes the way our brain handles stress.”

The research team hopes that their work will encourage more public health policies that promote the reduction of salt in processed foods.

The findings appear in Cardiovascular Research.

Salt Consumption Is Above Healthy Levels

Sodium is an essential element that helps regulate the movement of nutrients in and out of cells. The human body requires only a small amount of sodium, which combines with chloride to make up common table salt.

According to the 2020–2025 Dietary Guidelines, Americans should consume less than 2,300 milligrams (mg) of sodium daily. But the Centers for Disease Control and Prevention (CDC) estimates Americans eat over 3,400 mg every day.

Evangeline Mantzioris, a dietitian and program director of nutrition and food sciences at the University of South Australia, discussed the epidemic of high salt in an April 2022 podcast. She was not involved in the present study.

When we eat too much salt, Mantzioris explained: “It gets absorbed into our intestine and our blood […] It draws fluid into the blood vessels [and] increases the blood pressure against the blood vessel wall — and this is what we call high blood pressure.”

She added that aging and certain health conditions, including preeclampsia, low birth weight, and chronic kidney disease, can increase salt sensitivity. In turn, “our body is less able to deal with all the processes that it needs to keep healthy,” she noted.

Studying The Stress-Inducing Effects Of Salt

Dr. Bailey and his colleagues tested their hypothesis on commercially sourced male mice. They fed the mice with either a control, low sodium diet or a high-salt diet.

The researchers measured stress hormone levels in the morning and evening for up to 8 weeks. They took blood samples to assess the HPA axis response to stress.

Further, the scientists collected and analyzed tissue samples for genetic information about the hypothalamus, liver, kidney, and heart.

The study’s authors concluded that their research showed “functional evidence of a novel, direct connection between dietary salt intake and HPA axis activation.”

High salt intake led to high salt levels in the blood, a condition called hypernatremia, as well as fluid imbalance. Although the rodents had free access to water, they experienced an “activation of a water conservation response.”

The researchers proposed that a “high-salt diet is emerging as an important behavioral modifier, at least in rodents.”

Limitations Of Animal Research

This study focused on male mice, which may limit extending some of the findings to humans.

The COVID-19 pandemic restricted research capabilities, so the authors could not examine salt intake and HPA activity in female mice.

“In humans, the amount of the hormone that appears in the urine is higher in people that eat more salt, and this is true in women and men,” Dr. Bailey said.

“There is also evidence that this stress system (hypothalamic-pituitary-adrenal axis) shows sex-different response[s] to stress. In females, the rapid response is often larger, and over time, females have a higher risk of developing some types of stress-related psychiatric disorders. My hypothesis is that the effect of salt would be larger in females.”

Areas For Future Study

The researchers believe that their work “warrants systematic investigation because detrimental changes in brain health in response to high dietary salt intake may have important real-world consequences.”

Dr. Bailey shared his plans for future trials:

“We are planning a study in healthy volunteers where we provide meals to control the amount of salt and ask individuals to undertake tasks such as problem-solving against the clock. We know that these tasks activate the stress system: we can measure the hormone in saliva and heart rate.”

Reducing Hidden Salt In Processed Foods

Since excess salt presents an urgent health concern, Dr. Bailey hopes that governments will champion the cause of reducing salt in processed foods.

“For most governments, this needs to be working with food manufacturers to reduce sodium content in staple food products […] The strategies that have worked best have been collaborative partnerships to establish agreed time-dependent targets for reduction, independently monitored.”

– Matthew Bailey, Ph.D., lead author of the study

Dr. Bailey also recommended replacing table salt with low-salt alternatives such as sodium chloride or potassium chloride. He cited recent studies attesting to their effectiveness.

Still, not all salt may be bad for you, according to Mantzioris. The dietitian maintained that the amount of table salt we sprinkle on our food is generally fine. But she warned that the salt danger lies hidden in ultra-processed foods.

“Rather than being concerned about what you might add in the cooking or at the table, have a closer look at the amount of salt that’s in the processed foods you purchase,” Mantzioris said.

Important Notice: This article was originally published at www.medicalnewstoday.com by Jeanna D. Smiley where all credits are due. Fact checked by Anna Guildford, Ph.D.


The watching, interacting, and participation of any kind with anything on this page does not constitute or initiate a doctor-patient relationship with Dr. Farrah™. None of the statements here have been evaluated by the Food and Drug Administration (FDA). The products of Dr. Farrah™ are not intended to diagnose, treat, cure, or prevent any disease. The information being provided should only be considered for education and entertainment purposes only. If you feel that anything you see or hear may be of value to you on this page or on any other medium of any kind associated with, showing, or quoting anything relating to Dr. Farrah™ in any way at any time, you are encouraged to and agree to consult with a licensed healthcare professional in your area to discuss it. If you feel that you’re having a healthcare emergency, seek medical attention immediately. The views expressed here are simply either the views and opinions of Dr. Farrah™ or others appearing and are protected under the first amendment.

Dr. Farrah™ is a highly experienced Licensed Medical Doctor certified in evidence-based clinical nutrition, not some enthusiast, formulator, or medium promoting the wild and unrestrained use of nutrition products for health issues without clinical experience and scientific evidence of therapeutic benefit. Dr. Farrah™ has personally and keenly studied everything she recommends, and more importantly, she’s closely observed the reactions and results in a clinical setting countless times over the course of her career involving the treatment of over 150,000 patients.

Dr. Farrah™ promotes evidence-based natural approaches to health, which means integrating her individual scientific and clinical expertise with the best available external clinical evidence from systematic research. By individual clinical expertise, I refer to the proficiency and judgment that individual clinicians acquire through clinical experience and clinical practice.

Dr. Farrah™ does not make any representation or warranties with respect to the accuracy, applicability, fitness, or completeness of any multimedia content provided. Dr. Farrah™ does not warrant the performance, effectiveness, or applicability of any sites listed, linked, or referenced to, in, or by any multimedia content.

To be clear, the multimedia content is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health providers with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read or seen in any website, video, image, or media of any kind. Dr. Farrah™ hereby disclaims any and all liability to any party for any direct, indirect, implied, punitive, special, incidental, or other consequential damages arising directly or indirectly from any use of the content, which is provided as is, and without warranties.