Written By: Ava Astilla
We have all been there: the grocery store check-out line, the football game concession stand, the gas station snack aisle –many places filled with ultra-processed food options. Ultra-processed foods (UPFs) are highly available, addictive, and unhealthy, but the impact that these foods have on our mental health is also a serious concern. Making up about 60% of the calories in an average American diet (1), UPFs have been linked to a risk of cognitive decline, anxiety, and depression (2). Let’s explore the impact of IPFs on our mental health and what we can do to prevent it.
What are ultra-processed foods?
Ultra-processed foods (UPFs) are composed of ingredients such as colors, artificial flavors, sweeteners, emulsifiers, and preservatives that are rarely used in homemade recipes (3). These ingredients are created by a multitude of industrial processes, and they make up UPFs that are typically nutritionally unbalanced. Brazilian researchers developed the NOVA classification system (4), which assigns categories to foods that have undergone different levels of processing. High levels of added sugars, saturated and trans fats, sodium, and low levels of protein, fiber, and certain micronutrients make UPFs into energy-dense products3. Non-nutrient components, like additives and chemicals, also characterize UPFs and are frequently added to food products to extend shelf life and improve sensory qualities.
Who consumes UPFs?
One reason for high UPF consumption levels comes from the popularity of humectants, color stabilizers, and emulsifiers that are added to foods to make them more shelf-stable. Making up about 60% of what adults eat and 70% of what kids eat (4), UPFs are making up a large portion of what the typical American consumes. The convenience and affordability of UPFs have allowed them to dominate the food supply. In a study conducted to examine the UPF intake of low-income Americans, participants from the highest quartile of UPF consumption were younger and more likely to be enrolled in community health centers (5). Participants from this quartile were also more likely to be men, Black, have lower education, and lower income levels.
How do UPFs impact mental health?
UPFs, specifically UPFs containing artificial sweeteners, have been linked to an increase in the risk of depression (6). A study published in 2023 discovered the association between artificial sweetener consumption and an increased risk of depression in women, and it identified artificial sweeteners to induce purinergic transmission to the brain which may cause the development of depression (7). Purinergic transmission occurs when the brain doesn’t release the right amount of ATP, and ATP is crucial for binding to chemicals like serotonin and dopamine (known as “feel-good” chemicals). ATP binds with such chemicals to send messages between neurons, and the disruption of ATP binding causes inflammation in the brain – the reason why scientists believe there may be a link between UPF consumption and depression. This study was only limited to women, but its results demonstrate our need for caution when consuming ultra-processed foods at high levels.
Regarding the ways that food can impact our brain’s responses, the gut microbiome has been closely linked to the brain. Gut microbes impact sleep and stress reactivity and influence mood, memory, and cognition (8). Co-author of the artificial sweetener study listed above, Dr. Andrew Chan, stated that those who eat a lot of UPFs usually have guts that are more pro-inflammatory, causing the gut to release molecules that influence depression risk.
What can we do to make better choices?
UPFs tend to contain more calories in a bite versus unprocessed foods (4), and the factors of UPFs that cause people to overeat are still being studied. For now, trying to consume more plant-based meals or shifting to a plant-based diet is an encouraged plan for lowering your intake of UPFs. Not all UPFs are made the same, and it is important to remember that while foods like whole grain breads and certain yogurts may technically be categorized as UPFs under the NOVA classification system, such products are still healthy options. Reducing your intake of UPFs with high salt, sugar, and fat and making substitutions for minimally or unprocessed foods is a great step in improving your nutrition and lowering your risk for many health issues. Enjoying all foods in moderation and making healthy substitutes is a great way to be proactive in trying to protect our mental health!
References:
1. Wadyka S. The Link Between Highly Processed Foods and Brain Health. The New York Times. https://www.nytimes.com/2023/05/04/well/eat/ultraprocessed-food-mental-health.html. May 4, 2023. Accessed October 30, 2023.
2. Ultra-processed foods linked to poorer brain health. Harvard T.H. Chan School of Public Health. https://www.hsph.harvard.edu/news/hsph-in-the-news/ultra-processed-foods-poorer-brain-health/. May 23, 2023. Accessed October 30, 2023.
3. Tristan Asensi M, Napoletano A, Sofi F, Dinu M. Low-Grade Inflammation and Ultra-Processed Foods Consumption: A Review. PubMed Central. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10058108/. March 22, 2023. Accessed October 30, 2023.
4. Godoy M. What we know about the health risks of ultra-processed foods. NPR. https://www.npr.org/sections/health-shots/2023/05/25/1178163270/ultra-processed-foods-health-risk-weight-gain#:~:text=Ultra%2Dprocessed%20foods%20currently%20make,70%25%20of%20what%20kids%20eat. May 25, 2023. Accessed October 30, 2023.
5. Wang L, Pan X-F, Munro HM, Shrubsole MJ, Yu D. Consumption of ultra-processed foods and all-cause and cause-specific mortality in the Southern Community Cohort Study. Science Direct. https://www.sciencedirect.com/science/article/pii/S0261561423002716#abs0010. August 18, 2023. Accessed October 30, 2023.
6. Samuthpongtorn C, Nguyen LH, Okereke OI, et al. Consumption of ultraprocessed food and risk of depression. JAMA Network. https://jamanetwork.com/journals/jamanetworkopen/fullarticle/2809727. September 20, 2023. Accessed October 30, 2023.
7. Sullivan K. Ultraprocessed Foods linked to depression, study finds. NBC News. https://www.nbcnews.com/health/mental-health/ultraprocessed-foods-linked-depression-study-finds-rcna106811. September 20, 2023. Accessed October 30, 2023.
8. Galland L. The gut microbiome and the brain. PubMed. https://pubmed.ncbi.nlm.nih.gov/25402818/. December 17, 2014. Accessed October 30, 2023.
9. Atlas Blog. https://atlasbiomed.com/blog/content/images/2020/09/2020-09-09-3--Diet-and-mental-health-200914--1.png.
Hi Ava,
This article is extremely insightful! I have never really considered the impact on mental health specifically caused by UPFs beyond general physical health concerns. I would love to study this further in my own personal diet. I wonder if times where I have felt more sad/anxious have been related to higher consumption of UPFs. It's also alarming to think that over half the food we consume can be classified as UPFs. However, it can be extremely difficult to find low-cost, healthy alternatives, which widens nutrition disparities amongst income levels. Policy initiatives to fund healthy food banks or regulate healthy food costs could be extremely effective at addressing these inequities. Alterations to UPFs, even in small increments over time,…
Hey there,
I totally relate to the struggle of facing all those tempting ultra-processed foods at the grocery store. It's hard to resist their convenience, but you're absolutely right in pointing out the impact they can have on our mental health. They make up a significant chunk of our diets, and that's a concern.
Ultra-processed foods are a tricky bunch, filled with all artificial ingredients and additives rarely used in homemade cooking. The NOVA classification system sounds like a helpful tool to understand them better. The high sugar, fat, and sodium content makes them not so great for our health. It's quite surprising to learn how much UPFs we all consume. Convenience and affordability play a big role in that.…