Processed Food Blues

Highly processed foods have long been linked to health risks, such as diabetes and obesity, but new research shows that a diet high in preservatives and artificial flavors may harm mental health, as well.

bar graph depicting the percentage of ultra processed foods consumed and likelihood of developing depressive symptoms

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The enormous amount of ultra-processed foods Americans eat deeply impacts our mental well-being. Sixty percent of all the calories Americans consume come from foods like breakfast cereals, processed meat, and frozen meals with artificial additives that ensure lengthy shelf-lives.

For years we have known that eating processed foods is linked to an increased risk of diabetes, obesity, and even cancer. More recent discoveries show that a processed diet high in preservatives and artificial flavors greatly affects our brain health, too.

Eric Hecht and colleagues explored the link between the amount of ultra-processed foods a person eats and their mental health. Analyzing data from the National Health and Nutrition Examination Survey, researchers explored the link between ultra-processed food consumption and depression. The study compared the mental health outcomes between adults consuming approximately 80% or more of their calories from ultra-processed foods to those consuming less than 20%.

The graph above shows that respondents who ate the most ultra-processed foods were 81% more likely to experience depression symptoms than those with the lowest consumption level. They were also more likely to report feeling anxious or mentally unhealthy more days per month.

The authors speculate that ultra-processed foods impact mental health through the gut. The chemical additives and lack of fiber in ultra-processed foods may limit the variety of beneficial bacteria in our gut and thereby contribute to chronic inflammation, an immune state which has been linked to a host of mental and physical conditions, including the development of depression.

Foods laden with preservatives and artificial flavors often bring us comfort and convenience in the short term. But they may come at the expense of our long-term brain health and wellbeing.

Databyte via Eric M. Hecht, Anna Rabil, Euridice Martinez Steele, et al. Cross-sectional examination of ultra-processed food consumption and adverse mental health symptoms. Public Health Nutrition, 2022.