Fish Oil and Depression: What’s the Connection?

By: Michael Lam, MD, MPH; Justin Lam, ABAAHP, FMNM

A new study on Fish oil and depression medicine indicate that they can be beneficial to your health when taken together.Emerging research shows an intriguing link between fish oil and depression. Specifically, studies show that using nutritional supplements—such as fish oil—concurrently with medication taken for depression may increase drug effectiveness. Millions suffer from depression, and fish oil could be crucial for the management of the condition. Research shows that when depression medication is paired with specific supplements, such as vitamin D and omega-3 fish oil, it can actually lessen symptoms of depression.

According to the Substance Abuse and Mental Health Services Administration (SAMHSA), 6.7% of all U.S. adults (ages 18 and older) experienced at least one major depressive episode in the year 2014. This means that almost 16 million adults per year are affected by relatively severe depression. This same organization states that in the United States, major depression was among one of the most prevalent mental conditions. Nearly 17% of people will be affected by depression at least once in their lives.

Depression can cause feelings of unhappiness and an inability to enjoy things you were once interested in. This results in decreased functioning in many aspects of life. Antidepressants are medications used in the treatment of depression that function by affecting chemicals in the brain, otherwise known as neurotransmitters.

A study that was recently published in the American Journal of Psychiatry (AJP) explained what occurred when certain supplements were given with antidepressants. The study examined 40 different clinical experiments that tested nutritional supplements such as vitamin D, zinc, and omega-3s administered along with antidepressants. These supplements are sometimes referred to as nutraceuticals , or nutritional add-ons. This study showed fewer symptoms of depression among subjects who also consumed omega-3s (fish oil) as opposed to those who only took the antidepressant.

Other nutraceuticals also had a positive effect when combined with antidepressants, including vitamin D, methylfolate (a type of folate), and S-adenosylmethionine (a man-made imitation of a naturally occurring compound that facilitates maintenance of chemicals in the brain and cells).

Fish oil and depression, have been linked together due to the fatty acid levels within the body.Studies indicate that the supplements, or nutraceuticals, may actually target some of the same pathways and brain centers as the antidepressants do. Although research does not yet provide a clear mechanism, the supplementation of omega-3 fatty acids showed potential benefit in the area of the brain that is associated with mood and depression.

According to Jerome Sarris, who manages a research group for mental health in Australia, the omega-3s from fish oil activate natural activities in the brain and could improve mood. However, it is yet to be determined if the enhanced mood is due to the combination of fish oil and depression medicine or if two independent but harmonizing processes are occurring.

Studies on Fish Oil and Depression

Dr. Richard Friedman, a Cornell clinical psychiatry professor, is guardedly confident about the study because it yields potentially positive results. Although he was not a part of the study, he suggested that the data warrants a bigger, randomized sample for rigorous medical trials of nutraceuticals and the role they play in depression treatment.

Although this study did not reveal any cause for concern with regard to safety of supplementation, a few mild side effects were reported by those taking fish oil for depression. The most common were constipation, diarrhea, and an upset stomach. Even though the nutraceuticals were relatively safe, it is always best to discuss fish oil and depression with your doctor. This is especially important when taking other medications.

Fish oil provides the body—and especially the brain—with fatty acids such as docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA). People who suffer from depression often have low levels of these fatty acids in the blood, a possible link between fish oil and depression. EPA and DHA are polyunsaturated fats, also known as omega-3 fatty acids, that can be found in fish that live in cold water, hence the term “fish oil.” Consuming these omega-3 fatty acids is crucial to your health because the human body cannot make them itself. They may therefore be referred to as essential fatty acids. A study performed in February of 2016 detected that the majority of patients (75%) with mood or anxiety disorders had significantly lower levels of both whole blood DHA and EPA than the general population. Another study published in 2014 by the U.S. National Library of Medicine and the National Institutes of Health found that omega-3 fatty acids had a substantial clinical benefit for patients with depression and those who have been diagnosed with major depressive disorder (MDD). The exact link between omega-3 fatty acids from fish oil and depression treatment—especially when taken with antidepressants—is not completely clear. However, since people who suffer from depression often had lower levels of essential fatty acids such as DHA and EPA, supplementing with fish oil may be effective.

Fish oil and depression treatment can be difficult.Dr. Friedman also expressed concern for the current regulation of nutraceuticals such as fish oil in terms of purity and quality. Currently, finding a proper Fish oil and depression treatment can be difficult, and understanding the many different labels can be extremely confusing. The most important aspects of the label include the serving size and how much combined DHA and EPA—or omega-3s—the supplement provides, a measurement that is given in milligrams (mg). It is also important to note that there is a difference in the actual fish oil concentration and the omega-3 concentration. Some marketing on the labels of fish oil will claim to have more total fish oil, but this does not necessarily mean that there are larger quantities of the essential fatty acids.

Labdoor, a company that specializes in testing label accuracy and purity of supplements, recently performed a study that investigated 52 top-selling fish oils. They found that 31 of them had levels of total omega-3 that were more than 10% different from what their label claimed. There was also a large inconsistency in the actual and claimed levels of DHA and EPA. There are numerous benefits to taking fish oil, but it is important to use an appropriate supplement.

Depression is a very common and well-studied condition among Americans, yet there is still much that is unknown, especially about antidepressants. For example, some people have better results on various medications. The precise mechanisms by which they function are also still undetermined. A recent study showed that 30-45% of a reaction to an antidepressant is actually a placebo response. The link between fish oil and depression is an even more recent discovery, and is still poorly understood.

While this research on the efficacy of fish oil needs to be duplicated, especially with a larger group, the consumption of supplements such as fish oil could be a simple and inexpensive way to enhance treatment of depression.

Studies on Fish Oil and Depression Continued

A study published in April of 2016 by the Journal of Psychiatric Research found that when fish oil was given for depression for six weeks, the seriousness of depression decreased. These researchers thought this could be related to the increased DHA levels and improvements that occurred in the integrity of white matter.

White matter is located in both the brain and spinal cord and is comprised of nerve tissue that has a myelin sheath (fatty tissue that functions as insulation). The main function of white matter is to connect different areas of the brain and to ensure messages (electrical signals) are delivered to the right place. The significance of this finding is summed up in a study completed in 2011 by the American College of Neuropsychopharmacolocy, which found that the chronic inflammation of white matter could play a role in depression. Fish oil may alleviate depression by helping to maintain the integrity of white matter and reduce chronic inflammation.

The Fatty tissue within your brain that sends brain signals link Fish oil and depression together.When stress occurs, the body uses a system called the NeuroEndoMetabolic (NEM) stress response to protect itself. Inflammation can result from stress and causes a cascade effect in the body. Cortisol, the chief anti-stress hormone, is released by the adrenal glands to fight any inflammation as one of the ways of protecting the body. The chronic inflammation response caused by cell-mediated immunity is linked to depression. In fact, a widely used type of antidepressant medication, selective serotonin reuptake inhibitors (SSRIs), have powerful anti-inflammatory properties.

The Journal of American Medical Association published a study in 2002 that found nearly one in three people with depression do not benefit from existing treatments. They found that taking fatty acids, such as the EPA found in fish oil, resulted in fast improvement. In another study, eicosapentaenoic acid (EPA) was also found to effectively improve depression in patients with bipolar disorder.

Omega-3s play so many important roles in our bodies in addition to combating depression. According to the Mayo Clinic, fatty acids from omega-3s are believed to improve cholesterol levels, decrease risk of coronary heart disease, and play a beneficial role in cancer treatment. Recommended levels of fish oil supplements could lower the risk for heart attack, levels of triglycerides, and abnormal heartbeat. Omega-3s may also decrease stroke risk among patients with heart conditions. EPA and DHA from fish oil are also thought to help with high blood pressure and atherosclerosis, or the hardening of arteries.

Since your body doesn’t produce these essential fatty acids itself, it is important to incorporate them into your daily diets. One of the most convenient and healthy ways to do this is through fish oil supplementation. It is clear that both DHA and EPA, and omega-3 fatty acids generally, have a wide array of benefits for cardiovascular health, brain function, the treatment of depression, and the body as a whole.

Fish Oil and Depression in the Context of Adrenal Fatigue

The association between fish oil and depression is particularly important for those suffering from Adrenal Fatigue, as mild depression is a sign and symptom of Adrenal Fatigue Syndrome (AFS). Those with Adrenal Fatigue, do not have the energy to live the life they wish to. This can be a difficult, frustrating, and depressing reality. Inflammation also tends to increase in your body with AFS, which may also trigger depression. In stage four of Adrenal Fatigue, defined as failure, the use of antidepressants or other hormone therapy can actually make matters worse.

 Taking Fish oil and depression medicine may or may not benefit you. Any disruption to the NeuroEndoMetabolic (NEM) stress response system can cause a cascade of responses that include hormonal, metabolic, neuro-affective, cardionomic, inflammatory, and detoxification reactions in the body. The NEM system is very effective in fighting and defending the body against stress. It uses a team of organs and systems that work together to bring the body back to homeostasis. By realizing that the body represents a whole team of functioning parts and systems rather than individual, disconnected pieces, you can begin to understand how to maximize your health potential and identify the effect of incorporating supplements, such as fish oil, into your diet. Along with suitable rest, removal of stressors, and an appropriate diet, specific nutritionals play a key role in Adrenal Fatigue recovery. Although more studies and larger clinical trials are warranted, omega-3s in fish oil seem to be beneficial to the body on many levels, notably in the treatment of depression, especially when taken with antidepressant medication.

Although fish oil taken for depression has been found to be relatively safe for consumption to aid in treatment, it’s extremely important to speak with a doctor or dietician about finding a dose of fish oil that works for you. Such an expert can also consider your medical history, current medications, and health goals to advise you properly. Research shows promising results for the many who suffer from depression when fish oil is incorporated into their treatment plan.


Works Cited

Center for Behavioral Health Statistics and Quality. (2015). Behavioral health trends in the United States: Results from the 2014 National Survey on Drug Use and Health (HHS Publication No. SMA 15-4927, NSDUH Series H-50). Retrieved June 21, 2016, from

What Is Depression? (n.d.). Retrieved June 23, 2016, from

Messamore, E., & Mcnamara, R. K. (2016). Detection and treatment of omega-3 fatty acid deficiency in psychiatric practice: Rationale and implementation. Lipids in Health and Disease, 15(1). doi:10.1186/s12944-016-0196-5

Grosso, G., Pajak, A., Marventano, S., Castellano, S., Galvano, F., Bucolo, C., . . . Caraci, F. (2014). Role of Omega-3 Fatty Acids in the Treatment of Depressive Disorders: A Comprehensive Meta-Analysis of Randomized Clinical Trials [Abstract]. PLoS ONE, 9(5). doi:10.1371/journal.pone.0096905

Top 10 Fish Oil Supplements – Labdoor. (n.d.). Retrieved June 23, 2016, from

Chhetry, B. T., Hezghia, A., Miller, J. M., Lee, S., Rubin-Falcone, H., Cooper, T. B., . . . Sublette, M. E. (2016). Omega-3 polyunsaturated fatty acid supplementation and white matter changes in major depression. Journal of Psychiatric Research, 75, 65-74. doi:10.1016/j.jpsychires.2015.12.007

White matter cells linked to depression. (n.d.). Retrieved June 23, 2016, from

Puri, B. K. (2002). Eicosapentaenoic Acid in Treatment-Resistant Depression. Archives of General Psychiatry, 59(1). doi:10.1001/archpsyc.59.1.91-a

Frangou, S. (2006). Efficacy of ethyl-eicosapentaenoic acid in bipolar depression: Randomised double-blind placebo-controlled study. The British Journal of Psychiatry, 188(1), 46-50. doi:10.1192/bjp.188.1.46

Omega-3s fatty acids, fish oil, alpha-linolenic acid. (2013, November) Retrieved June 21, 2016, from

© Copyright 2016 Michael Lam, M.D. All Rights Reserved.

Consult your doctor and ask if fish oil and depression medicine is good for you.
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Beautiful! Thank you once again. You are a truly AMAZING coach of health and life. I wish every doctor in the health field was even half as committed as yourself. It is extremely hard these days to find even a good doctor, but if a person finds a great one, they need to cherish them.