Could your diet affect how stressed you feel? A new study from Binghamton University, State University of New York, suggests it might. Researchers found that a Mediterranean diet – rich in vegetables, fruits, whole grains and healthy fats – can help lower your perceived stress levels, while a traditional Western diet high in processed foods and sugar can have the opposite effect. This finding adds to the growing body of evidence that our diet affects not only our physical health but also our mental wellbeing.
The study was published in Nutrition and health.
The study, led by Lina Begdache, associate professor of health and wellness studies, aimed to examine the relationship between diet and perceived stress. Perceived stress refers to how much stress a person feels, regardless of the actual stressors in their life. Begdache and her team wanted to know if different dietary habits, particularly the Mediterranean and Western diets, affect this stress perception.
Previous studies have found links between the Mediterranean diet and improvements in mental and physical health. However, little is known about how this diet affects perceptions of stress – that is, how much stress someone thinks they can handle. On the other hand, most studies on diet and stress have focused on how stress affects eating habits, leaving a gap in understanding the inverse relationship: how diet might affect stress.
To investigate this, Begdache and her colleagues conducted a large-scale survey with 1,591 participants. Participants, mainly students from various universities, were asked about their dietary habits and their perceived stress levels. The survey included questions about the frequency of consumption of certain food groups characteristic of either the Mediterranean or Western diet. In addition, participants answered questions from the Perceived Stress Scale, which measures how much stress they feel in their lives, and the Kessler Psychological Distress Scale, which assesses psychological distress.
The research team used a machine learning model to analyze the data, looking for associations between the foods participants ate and the levels of stress and psychological distress they reported. This approach allowed them to identify patterns in how different dietary habits are related to feelings of stress.
Participants who followed a Mediterranean diet reported lower levels of perceived stress and psychological distress. Specifically, the study found that eating foods like green leafy vegetables, fruits, nuts, whole grains and fish – all staples of the Mediterranean diet – was associated with lower stress levels. These foods are rich in nutrients that support brain health, including vitamins, minerals and antioxidants that help regulate neurotransmitters, the chemicals in the brain that affect mood and stress responses.
Conversely, the study found that participants who ate a Western diet, which is characterized by high consumption of processed foods, sugar, and high-glycemic index foods such as white bread and sweets, reported higher levels of perceived stress and psychological distress. Foods such as fast food, sugary snacks, and caffeinated beverages were particularly associated with higher stress levels. These findings suggest that the Western diet may worsen stress by promoting inflammation and disrupting the balance of stress-regulating hormones.
“Stress is considered a precursor to psychological stress, and research, including our own, has shown that the Mediterranean diet alleviates psychological stress,” Begdache said. “So part of the puzzle may be explained by the fact that the Mediterranean diet may be associated with a reduction in the negative components of perceived stress and an improvement in its positive attributes.”
Interestingly, the study also found that some components of the Western diet, such as meat and dairy products, were not as strongly linked to increased stress as other Western dietary components such as fast food and sugary snacks. In fact, certain animal proteins showed a slightly negative link to stress, which the researchers believe may be due to their content of nutrients such as tyrosine, a precursor to the mood-regulating neurotransmitter dopamine.
While the results are compelling, the study does have some limitations. One of the main limitations is its cross-sectional design, meaning that researchers only observed participants’ dietary habits and stress levels at a single point in time. This design makes it difficult to establish causality – whether the Mediterranean diet actually leads to lower stress levels or whether people who are less stressed are more likely to eat a Mediterranean diet. Longitudinal studies that follow participants over a longer period of time would be needed to establish a clearer cause-and-effect relationship.
Another limitation is the reliance on self-reported data. Participants may not have accurately recalled or reported their dietary habits, which could bias the results. In addition, although the sample was large, it was primarily made up of college students, a group that may not represent the general population. Future research should aim to include a more diverse sample to see if the results hold across different age groups and backgrounds.
Finally, the study raises new questions for future research. For example, which specific components of the Mediterranean diet are most effective at reducing stress? Are there certain nutrients or food combinations that have the greatest impact? In addition, research could examine the biological mechanisms underlying the relationship between diet and stress, such as the role of inflammation and gut health in influencing psychological well-being.
“Most foods in the Mediterranean diet are rich in antioxidants and anti-inflammatory compounds,” the researchers concluded. “They also contain nutrients that are building blocks for neurotransmitters that regulate mood and stress. The Western diet, on the other hand, lacks these nutrients and contains a higher ratio of omega-6 to omega-3 fats, which promote inflammation. Consumption of processed, high-sugar foods and caffeine is also associated with higher cortisol levels, which increases the stress response. Overall, the study’s findings pave the way for future research on the effects of dietary habits and their relationship to different components of the stress response and psychological distress.”
Authors of the study “Effects of Mediterranean and Western dietary habits on perceived stress and psychological distress” were Ushima Chowdhury, Sabrina Bubis, Katerina Nagorny, Megan Welch, Lexis Rosenberg and Lina Begdache.
