From a young age, we are taught that eating our fruits and vegetables everyday is very important. If we want to keep our bodies and our brains in tip top shape, we learned that a consistent stream of healthy whole foods will keep us energized and alert. This means that what we feed ourselves on a daily basis has a major impact on how well we function, and while a lot of us may consider how the food we eat affects our physical appearance, the food we consume has a direct impact on our mental health and processes as well. In the US, about 60-90% of the American diet consists of ultra-processed foods, such as cookies, sweetened beverages, chips, and more.1 With so many processed foods being consumed on a daily basis, the US has seen a connection in the rise in mental health issues as researchers find more links between ultra-processed foods and mental health outcomes. In this blog, we will explore ultra-processed foods and how their consumption may impact the development of mental health issues, such as anxiety and depression.
What are ultra-processed foods?
The term ‘ultra-processed foods’ was created by researchers to describe a group of foods that have been extremely processed during their production. There are various levels as to how food can become processed, ranging from minimally to ultra processed. On one end of the spectrum, there are unprocessed or minimally processed foods, and these are the items that have no added ingredients to them. Minimally processed foods include things such as milk, fish, eggs, vegetables, grains, nuts and seeds. Foods that have not been altered from their natural state are considered to be minimally processed. When processed ingredients such as salt, oil, or sugar are added to minimally processed foods, they are known as processed foods. Foods like canned fruits and vegetables, homemade cheeses, breads, or jams may be classified as processed foods. However, foods come to be ultra processed when five or more extra ingredients are added to the food. These extra ingredients are things such as additives, sweeteners, preservatives, emulsifiers, artificial flavors and colors. These foods typically go through multiple forms of factory processing, and these manipulations usually contribute to the long-shelf life of ultra processed foods.
Some common ultra-processed foods include:
- Soda and artificially sweetened beverages
- Ice cream
- Flavored yogurts
- Cereals
- Hot dogs
- Frozen pizza, pasta, and pies
- Candies
- Cake mix
- Chips
- Packaged breads and buns
- Energy drinks
- Fast food items
Negative effects of ultra-processed foods
Ultra-processed foods contain high levels of saturated fat, sugar, and salt. Research shows that ultra-processed foods have more than 8 times the amount of added sugars than in processed foods, and 5 times more added sugars than in unprocessed, minimally processed, and processed ingredients combined together.1 This can serve as a major cause of concern as high levels of added sugar consumption can lead to chronic conditions such as cardiovascular disease, cancer, obesity and diabetes. In a past Remedy blog, we have discussed the connection between chronic conditions and their negative impacts on mental health. A study done over the course of 19 years demonstrated that there was a 31% higher mortality for individuals who had the highest consumption of ultra-processed foods versus the lowest.2 These foods promote the risks of chronic diseases, overeating, weight gain, and negative mental health outcomes.
Ultra-processed foods can be quite an attractive option for most Americans since these foods are cheap, convenient, and tasty. Even though many people understand that whole foods such as fruits and vegetables are more beneficial to their overall health, accessibility to ultra-processed foods is much higher than fresh, nutritious alternatives. Studies from the Association of American Medical Colleges and USDA have found that 54 million Americans are food insecure, while 23.5 million Americans live in food deserts.3 This translates into nearly 1 in 6 Americans struggling to eat food daily. In food deserts, people do not have easy access to affordable, nutritious food options within their community either due to income barriers or physical barriers. An area is considered to be a food desert if the supermarket is more than 1 mile away in an urban area or more than 10 miles away in a rural area.3 Poor diets and a lack of access to fresh foods add to the overconsumption of ultra-processed foods, and therefore contributes to a myriad of mental health issues.
Ultra-Processed Foods Affects Mental Health
The impacts of food on mental health is somewhat of a bidirectional relationship. The food that we consume can affect our mental health, and our mental health can affect the types of foods we decide to eat. Research has shown that poor diet quality can pose as a potential risk factor for developing mental disorders, especially depression.4 A 2023 study of over 30,000 individuals showed that individuals who consumed high levels of ultra-processed foods had higher smoking rates, higher BMI, lower levels of exercise, and comorbidities such as diabetes, hypertension.5 In addition, these participants with the highest levels of ultra-processed food consumption had increased risks for depression compared to those who consumed ultra-processed foods the least. Namely, consuming high amounts of artificially sweetened beverages and artificial sweeteners were associated with a greater risk of developing depression. Preliminary data suggests that these sweeteners may elicit specific purinergic activity in the brain that is associated with the development of depression. This study also found that decreasing ultra-processed food intake by at least 3 servings per day was associated with lowering the risk of depression.5 In addition, a 2022 study studied the positive effects of adopting a Mediterranean diet on moderate and severe depression. Participants in the study had been diagnosed with major depressive disorder, and were separated into a control group and a group that underwent a 12-week Mediterranean diet intervention that consisted of more fruits, fish, vegetables, whole grains and healthy fats. These participants in the intervention group saw a significant decrease in the amount of depressive symptoms they had compared to the control group.6
A meta-analysis of several studies concluded that the consumption of ultra-processed foods is also associated with anxiety symptoms, such as anxiety-induced sleep disturbances. Three cross-sectional studies done on 101,709 participants determined that high levels of ultra-processed food consumption was associated with higher odds of developing anxiety symptoms.4 Another study done on 2,680 Brazilian adolescents showed that there is an association between greater ultra-processed food intake and higher levels of internalizing symptoms such as social withdrawal and somatic complaints such as emotional distress.4 On the other hand, the prevalence of mental health issues can also influence the consumption of ultra-processed foods themselves. In Italy, a study showed that higher levels of post-traumatic stress disorder symptoms as a result of the COVID-19 pandemic were associated with higher levels of ultra-processed food consumption. In addition, another study demonstrated that individuals who work in highly stressful work-environments such as the industrial and retail sectors were more likely to consume ultra-processed foods.4
The components of ultra-processed foods can disrupt the brain
The mechanism by which ultra-processed foods can influence and be influenced by mental disorders is currently being studied by researchers. There are many non-nutritive components of these foods that may influence the brain pathways associated with mental disorders. For example, some data has suggested that greater intakes of artificial sweeteners such as aspartame, saccharin, and monosodium glutamate (MSG) may be associated with dysregulating the normal synthesis and release of brain chemicals related to mood disorders. Neurotransmitters such as dopamine, norepinephrine, and serotonin may be impacted by the chemicals and artificial components that make up ultra-processed foods. Other emulsifier ingredients found in ultra-processed foods such as polysorbate-80 and carboxymethylcellulose may negatively affect the gut microbiome by reducing its diversity and function. Disruption of the gut microbiome can increase the risk of inflammation in the brain and gut; and inflammation has a great impact on the incidence and development of mental disorders.4
Making Nutritional Swaps for Better Mental Health
It is definitely easier said than done to swap out ultra-processed foods for unprocessed or minimally processed foods. As mentioned above, food deserts can prevent so many people from making drastic changes to their diet when there are financial and physical barriers to more nutritious foods. In addition, ultra-processed foods are just so much quicker and easier to prepare than most other foods, especially if cooking isn’t a strong suit. However, making healthier choices does not have to feel so insurmountable. If you feel as though your diet mainly consists of ultra-processed, unhealthy foods, starting small can be the first step to a sustainably nutritious diet. Making quick changes to foods that you already know and love can help ease this process. For example, if you enjoy eating yogurt for breakfast, next time you go to the grocery store try to find yogurt that does not contain added sugars and sweeteners. Go for the plain option and opt to add your own fresh fruit for sweetness. If you enjoy drinking energy drinks, try to switch it out slowly for more natural energy sources such as green tea! Making these small, sustainable changes to your diet can be difficult, but not impossible with some creativity and determination.