When you’re anxious, you may look toward your circumstances for an explanation. But what if your tension could be the direct result of what you’re putting into your body?
If you’ve underestimated the link between your emotions and your diet, you are not alone. Most people trace their bad moods to parking tickets, subtle signs of disapproval from friends, and other troubling cues from the environment or those around them.
However, your physiology prefigures your reactions to your circumstances. If you change what’s going into your body, it will support different moods and interpretations.
Although frustrations and disappointments occasionally happen, operating from a foundation that supports wellness allows you to respond to difficulties with greater resilience. Your diet is essential to building this foundation.
I’d like to introduce you to a subtle, yet primary culprit of anxiety, depression, and even aggression: industrial seed oils.
How you cook matters as much as what you cook
Industrial seed oils are highly processed oils extracted from soybeans, corn, rapeseed, cottonseed, and safflower. They’re in all sorts of processed foods and even those with the non-GMO label. Due to their low costs, restaurants often repeatedly heat them to deep fry foods.
There are several problems with industrial seed oils, and they’ve been associated with health risks since their very recent introduction into the Standard American Diet (SAD) in the early 1900s (1). Some of these risks include heart disease, cancer, macular degeneration, progressive vision disruption, and eventual blindness (2).
These findings are troubling, but it’s easy to detach from their emotional reality. After all, progressive vision loss seems far off when there are hot pancakes on your countertop.
However, mental health issues hit you sooner. And even the most delicious foods lose their appeal when you discover they’re the reason you’re biting your nails, chronically fearful, or on edge.
Let’s discuss the evidence for the link between industrial seed oils and anxiety, depression, and aggression.
Industrial seed oils cause intestinal permeability
The human microbiome consists of bacteria, archaea, viruses and microbes that protect against pathogens, instruct the immune system, and directly or indirectly affect most of the body’s functions (3). About 90% of industrial seed oils are genetically modified organisms (GMOs), which are well-documented to cause intestinal permeability, also called “leaky gut” (4).
Leaky gut occurs when the sturdy barrier that lines your intestine becomes porous, allowing undigested food particles, microbial byproducts, and other foreign objects to leak into circulation (5). Said differently, leaky gut causes a breakdown in the boundary between the outside world and the immune system.
With leaky gut, everything you consume travels through the body unregulated. Not only can this result in the immune system attacking itself, but it causes inflammation, brain fog, disturbed sleep, and a loss of sex drive. The body’s stress response also gets provoked the via the hypothalamic-pituitary-adrenal (HPA) axis. Disruption of the HPA axis is widely accepted as a fundamental feature of anxiety and depression (6).
Industrial seed oils raise omega-6 to omega-3 levels
As explained by functional medicine expert Chris Kresser, anthropologists suggest that the ancestral diet helped early humans keep a strict 1:1 balance of omega-6 to omega-3 fatty acids, but the SAD tends to put most people at a ratio of 10:1 to 20:1 (12). The problem is that omega-6 is associated with the rise of several metabolites that are known to provoke inflammation, a defining feature of all chronic disease (13).
In addition to increasing your risk for heart attack and stroke (14), an imbalanced omega-6 to omega-3 ratio also has mental health consequences. A seven-year study linked high levels of omega-6 fatty acids to heightened risk of depression, noting that people with reduced levels of EPA and DHA (found in omega-3 fatty acids) developed mood disorders (15). Studies have also shown that if you eat a high omega-6 to omega-3 ratio you are predisposing yourself to cognitive decline and dementia (16).
For adequate levels of omega-3, prioritize foods such as mackerel, chia seeds, walnuts, herring, cod liver oil, flax seeds, and salmon. While omega-6 isn’t detrimental when found in whole foods, such as nuts and avocado, it becomes an issue because the SAD diet is full of omega-6 from processed sources while simultaneously lacking the required omega-3s that would help maintain a healthy ratio.
Trans fats found in seed oils are linked with high aggression
Trans fats occur as a result of the deodorizing process that takes place after manufacturers extract oil from seeds with petroleum-based solvents (12). Researchers studying the link between trans fat consumption and aggression found that trans fats not only cause memory issues and inhibit omega-3 production (which, as described above, provokes anxiety, depression, and cognitive decline), but they also cause irritability and aggression.
The study surveyed 1,018 men and women on their approaches to conflict, levels of impatience, and history of aggression. After controlling for various sociological measures, researchers found a strong link between trans fats and aggression (17). The authors found that regular trans fat consumption was greater predictor of aggressive tendencies than education, smoking, age, being of the male gender, and other factors (18).
Although observational studies have their limits, the link between trans fats and depression and anxiety is equally clear in other studies. One paper studied the effect of consistent consumption of hydrogenated vegetable fat on rats. The trans fat-fed rats displayed increased levels of orofacial dyskinesia (bizarre and uncontrollable movements of the face, jaw, mouth and tongue), fear, and anxiety, while rats fed a standard diet did not (19).
Other research indicates that trans fats cause hardening of the arteries, which reduces the responsiveness of a protein that controls cell differentiation, called transforming growth factor-beta. This protein is implicated in the development of cancer, heart disease, and diabetes (20).
Nevertheless, the power is yours.
There are three central steps in reducing your consumption of industrial seed oils. The first is to avoid processed food. Anything that comes in a bag demands extra scrutiny. Be aware that food companies strive to misdirect hungry grocery shoppers with misleading labels, such as “gluten free” or “contains whole grains” even while including high amounts of sugars and other unhealthy features.
There is also evidence that probiotics decrease the production of an inflammatory cytokine called TNF-A, and the presence of fewer inflammatory cytokines strengthens the integrity of the intestinal wall (5). Because inflammation factors into nearly all chronic diseases, this could be a leverage point in maintaining your health.
In particular, psychobiotic research demonstrates that a species of lactobacillus, a “friendly” form of bacteria, helps the body manage stress, alleviates anxiety, and soothes associated cognitive problems via communication with the brain on the microbiome-gut-brain axis (7). These include L. rhamnosus (8), which changes the expression of GABA receptors, reducing anxiety (9) and bifidobacterium longum, which reduces cortisol and eases depression and anxiety through its effect on the vagus nerve (10). Others include L. casei, L. paracasei, L. acidophilus, L. plantarum, L. fermentum, and L. rhamnosus (11).
You can find these microbes in yogurts with “live and active cultures,” kefir, tempeh, miso, sauerkraut, and other fermented foods. Your mood will also be served by eating prebiotics like fruits, vegetables, and legumes. These foods will strengthen the integrity of your gut lining and diversify your microbiome, two essential components of a healthy gut (and a less stressed mind).
To limit your consumption of processed seed oils, you might also limit your intake of restaurant food. The problem is that most restaurants opt for the oils that are cheapest then use them for frying, repeatedly bathing their food in the byproducts of the frying process (12). The repeated frying of these oils also promotes free radicals, which cause DNA damage (22).
In addition to these physical risks, you might also consider their psychological effects. While supporting local restaurants makes sense, if you don’t know how the restaurants are preparing the food, your knowledge of the impacts of what you’re eating will be limited. This is true even if the food you order is ostensibly healthy.
In The Yoga of Eating, Charles Eisenstein suggests that when we eat something, we eat everything that happened to the food, and in so doing, we affirm a certain version of the world. He writes: “When anonymous strangers grow, process, ship, and prepare our food, is it any wonder that we often feel consumed by loneliness, estranged from the world?” (23)
Whether it is because we are aware of all that occurred while cooking or because engaging in our own preparation process has the power to elevate it to an art form, we tend to feel the most nourished when every step of the food preparation and consumption process is a fully conscious and embodied act.
The significant impact that industrial seed oil plays on our mental and physical health shows that being healthy isn’t as straightforward as becoming a vegetarian or eating a ketogenic diet.
In other words, it’s not sensible to simply demonize macronutrients and expect to be healthy. Health requires a nuanced approach that takes into consideration our lifestyles, our species’ history with a food, and even more kaleidoscopic factors, such as the process our food underwent before it got to our plates.
Next time you have a difficult day, look beyond the stain on your vest or the troubling conversation with your best friend, and ask yourself whether the struggle began with what you had for lunch.
1) Paleo Leap, “What’s wrong with industrial oils?” Accessed February 12, 2021, https://paleoleap.com/whats-wrong-industrial-oils/
2) Seddon, J.M., Rosner, R.D., Sperduto, L., et al. (2001). “Dietary fat and risk for advanced age-related macular degeneration” Archives of Ophthalmology, 119, quoted in Chris Kresser, “How Industrial Seed Oils Are Making Us Sick,” February 19, 2019, https://chriskresser.com/how-industrial-seed-oils-are-making-us-sick/
3) Shreiner, A.B., Kao, J.Y., Young, V.B. (2016) “The gut microbiome in health and in disease,” Current Opinion in Gastroenterology 31, no. 1 (2015), 10.1097/MOG.0000000000000139
4) The Care Group PC. “Leaky Gut Treatment,” The Care Group P.C., February 6, 2020. https://www.thecaregrouppc.com/leaky-gut-syndrome/causes-and-treatment/.
5) Clapp, M. Aurora, N., Herrera, L. et al. “Gut microbiota’s effect on mental health: The gut-brain axis,” Clinics and Practice 7, no. 4, 2017. 10.4081/cp.2017.987
6) Gadek-Michalska, A., Tadeusz, J., Rachwalska, P. et al. “Cytokines, prostaglandins and nitric oxide in the regulation of stress-response systems,” Pharmacological Reports 65, no. 6., 2013. 10.1016/s1734–1140(13)71527–5
7) Gualttieri, P., Marchetti, M., Ciccoloni, G. et al. “Psychobiotics regulate the anxiety symptoms in carriers of allele A of IL-1 β gene: A randomized, placebo-controlled clinical trial,” Mediators of Inflammation 1, no. 11, 2020. 10.1155/2020/2346126
8) Zhou, L. & Foster, J. “Psychobiotics and the gut brain axis: in the pursuit of happiness,” Neuropsychiatric Disease Treatment 11, (2015). 10.2147/NDT.S61997
9) Bravo, J.A., Forsythe, P., et al. “Ingestion of Lactobacillus strain regulates emotional behavior and central GABA receptor expression in a mouse via the vagus nerve,” Proceedings of the National Academy of Sciences USA 108, no. 38, 2011. 10.1073/pnas.1102999108
10) Messaoudi, M., Violle, N., Bisson, J. et al. “Beneficial psychological effects of a probiotic formulation (Lactobacillus helveticus Roo52 and Bifidobacterium longum Ro175) in healthy human volunteers,” Gut Microbes 2, no. 4, 2011. 10.4161/gmic.2.4.16108
11) Leigh Stewart, “Stress, Anxiety, Depression and Mood: The Gut Microbiome Is Involved,” Atlas Blog (blog). August 14, 2020. https://atlasbiomed.com/blog/stress-anxiety-depression-microbiome/
12) Chris Kresser, “How industrial seed oils are making us sick,” Chriskresser.com (blog), February 19, 2019. https://chriskresser.com/how-industrial-seed-oils-are-making-us-sick/
13) Kones, et al. “N-3 polyunsaturated fatty acids and cardiovascular disease: principles, practices, pitfalls, and promises — A contemporary review,” Medical Principles and Practice 26, no. 6, 2018. 10.1159/000485837
14) DiNicolantonio & O’Keefe. “Omega-6 vegetable oils as a driver of coronary heart disease: the oxidized linoleic acid hypothesis,” Open Heart 5, no. 2, 2018. http://dx.doi.org/10.1136/openhrt-2018-000898
15) Berger, M. E., Smesny, S., Kim, S-W, et al. “Omega 6 to omega 3 polyunsaturated fatty acid ratio and subsequent mood disorders in young people with at risk mental states: a 7-year longitudinal study,” Translational Psychiatry 7, no. 8, 2017. 10.1038/tp.2017.190
16) Loef, M. & Walach, H. “Omega-6/omega-3 ratio and dementia or cognitive decline: a systematic review on human studies and bio evidence,” Journal of Nutrition in Gerontology and Geriatrics 32, no. 1, 2013. 10.1080/21551197.2012.752335
17) Golomb, B.A., Evans, M.A. White, H.L., Dimsdale, J.E. “Trans fat consumption and aggression,” PLos One 7, no. 3, 2012. 10.1371/journal.pone.0032175
18) University of California — San Diego. “More trans fat consumption linked to greater aggression, researchers find.” ScienceDaily. www.sciencedaily.com/releases/2012/03/120313122504.htm (accessed February 11, 2021).
19) Pase, C. S., Teixeira, A.M., Dias, V.T. et al. “Prolonged consumption of trans fat favors development of orofacial dyskinesia and anxiety-like symptoms in older rats,” International Journal of Food Science Nutrition 65, no. 6 2014. 10.3109/09637486.2014.898255.
20) Nathan Gray, “Scientists unlock how trans fats harm arteries,” Food Navigator. https://www.foodnavigator.com/Article/2010/11/03/Scientists-unlock-how-trans-fats-harm-arteries. (accessed February 12, 2021).
21) Jackson, S.E. Smith, L., Firth, J. et al. “Is there a relationship between chocolate consumption and symptoms of depression? A cross-sectional survery of 13,626 US adults,” Depression & Anxiety 36, no. 10, 2019. https://doi.org/10.1002/da.22950
22) Jaarin, K., Mustafa, M.R., Leong, X. “The effects of heated vegetable oils on blood pressure in rats,” Clinics 66, no. 12, 2011. 10.1590/S1807–59322011001200020
23) Eisenstein, Charles, The Yoga of Eating. (Washington, D.C.: New Trends Publishing, Inc., 2003), 30.
Note: This blog post is for informational purposes only and is not intended to be personal medical advice to the reader. I am not a medical professional and make no claims to be. If you have questions about your health, talk with your doctor.