Fish oil dosage depression

Omega-3 fatty acids for mood disorders

Omega-3 fatty acids are found primarily in fish oil and certain marine algae. Because depression appears less common in nations where people eat large amounts of fish, scientists have investigated whether fish oils may prevent and/or treat depression and other mood disorders. Two omega-3 fatty acids — eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) — are thought to have the most potential to benefit people with mood disorders.

How might omega-3s improve depression?

Different mechanisms of action have been proposed. For example, omega-3s can easily travel through the brain cell membrane and interact with mood-related molecules inside the brain. They also have anti-inflammatory actions that may help relieve depression.

More than 30 clinical trials have tested different omega-3 preparations in people with depression. Most studies have used omega-3s as add-on therapy for people who are taking prescription antidepressants with limited or no benefit. Fewer studies have examined omega-3 therapy alone. Clinical trials typically use EPA alone or a combination of EPA plus DHA, at doses from 0.5 to 1 gram per day to 6 to 10 grams per day. To give some perspective, 1 gram per day would correspond to eating three salmon meals per week.

Meta-analyses (research that combines and analyzes results of multiple studies) generally suggest that the omega-3s are effective, but the findings are not unanimous because of variability between doses, ratios of EPA to DHA, and other study design issues. The most effective preparations appear to have at least 60% EPA relative to DHA. While DHA is thought to be less effective as an antidepressant, it may have protective effects against suicide. Recent work at Massachusetts General Hospital and Emory University suggests that depressed individuals who are overweight and have elevated inflammatory activity may be particularly good candidates for EPA treatment.

Children and adolescents with depression may also benefit from omega-3 supplementation. At Harvard, there is a large study underway examining whether omega-3 supplementation (alone or in combination with vitamin D) can prevent depression in healthy older adults.

Omega-3s for other mental health conditions

Omega-3s have been studied in various mood disorders, such as postpartum depression, with some promising results. In bipolar disorder (manic depression), the omega-3s may be most effective for the depressed phase rather than the manic phase of the illness. The omega-3s have also been proposed to alleviate or prevent other psychiatric conditions including schizophrenia, borderline personality disorder, obsessive compulsive disorder, and attention deficit disorder. However, there is still not enough evidence to recommend the omega-3s in these conditions.

What dose of omega-3s is beneficial?

Doses for depression range from less than 1 g/day to 10 g/day, but most studies use doses between 1 and 2 g/day. In my practice, I recommend 1 to 2 g/day of an EPA+DHA combination, with at least 60% EPA, for major depression. I am more cautious in patients with bipolar depression, because the omega-3s may bring on mania, as can most antidepressants. In these individuals, I recommend using omega-3 cautiously, and preferably in combination with a prescription mood stabilizer.

Side effects and other safety considerations

Omega-3s are generally safe and well tolerated. Stomach upset and "fishy taste" have been the most common complaints, but they are less frequent now thanks to manufacturing methods that reduce impurities. Past concerns about omega-3s increasing the risk of bleeding have been largely disproven, but caution is still advised in people taking blood thinners or who are about to undergo surgery. As mentioned, caution is needed in people with bipolar disorder to prevent cycling to mania. Because omega-3s are important to brain development, and pregnancy depletes omega-3 in expectant mothers, supplementation should theoretically benefit pregnant women and their children. Fish consumption in pregnancy is supported by the FDA, but because we do not have long-term data on safety or optimal dosing of omega-3s in pregnancy, expectant mothers should consider omega-3 supplements judiciously.

The bottom line on omega-3s and mental health

Omega-3 fatty acids are promising natural treatments for mood disorders, but we need more research about how they work, how effective they really are, and their long-term safety before we can make conclusive recommendations for people managing mental health conditions or who wish to improve mood.


Dosage of Fish Oil for Depression & Anxiety

Fish Oil Supplement

Image Credit: Rahul Bhardwaj/iStock/Getty Images

Fish oil is an animal source of DHA and EPA omega-3 polyunsaturated fats. It is found most abundantly in fatty fish such as salmon and tuna, or as pill or oil supplement. Fish oil is widely known and used in the management of cardiovascular disease. However, studies have revealed it may also be used for many other brain functions, including the management of mood disorders and depression.

Video of the Day

Omega-3s Role in the Body

Omega-3s are essential fats. The body cannot produce them on its own. Food sources of Omega-3 include fatty fish such as salmon, tuna and mackerel; walnuts; and flaxseed and canola oil. Omega-3 acids are also widely available in supplement form as either fish oil or flaxseed oil. The National Institute of Health identifies a main function of omega-3 as helping reduce pain and swelling and to improve brain and nerve functions.

Fish Oil and Depression -- The Evidence

There is debate among researchers that fish oil is effective in treating depression. Dr. Daniel Hall-Flavin of the Mayo Clinic believes that fish oil can be used to treat symptoms of depression and anxiety. In a 2009 issue of "Neurosignals," a study suggested that fish oil may treat symptoms of depression along with medication. A review in "Age and Nutrition" states there is a inverse relationship between the incidence of seasonal depression and the amount of Omega-3's present in the an individual's blood plasma. However, Dr. Michael Maes, in "Neuroendocrinology Letters," concludes that DHA Omega-3 in fish oil can interfere with the function of regular anti-depressant drugs, but EPA Omega-3 does not intere with the function of antidepressants.

Appropriate Dosage

The appropriate dosage for treating depression and anxiety is inconclusive in research. According to the National Institute of Health, the dose for fish oil when treating depression is 9.3 g or 9,300 mg per day. This is far beyond the recommended dose of 1 to 4 g for cardiovascular disease. One study found that doses between 200 mg and 9 g is effective for treatment. However, Dr. Hall-Flavin recommends just 100 to 300 mg daily for treatment of depression and anxiety, although he stated that more research is needed to determine ideal doses.

Medication Interaction

High doses of Omega-3 fatty acids can have potential risks and interactions with medication. Do not begin a fish oil regimen without consulting a physician first. According to the NIH, there is a risk of bleeding from consuming more than 3 g of Omega-3 per day. Fish oil also may increase the effects of high blood pressure medications and lower blood pressure to severe levels. Birth control and Orlistat medications for weight loss may inhibit absorption of fish oil.

Related Reading

Omega-3 is an essential fatty acid that promotes cardiovascular health. High levels of the bad cholesterol -- low-density lipoproteins and triglycerides -- and low levels of the good cholesterol high-density lipoproteins can lead to cardiovascular disease. Omega-3 can help lower the blood content of the bad cholesterol and raise the good cholesterol. More recently, omega-3 has received attention for its possible positive effects on mood-disorders such as major depression, generalized anxiety disorder, panic disorder and bipolar disorder.

Omega-3 Fatty Acids

Omega-3 is found in high amounts in salmon, tuna, sardines, wild game and walnuts. The fat is "essential" because it must be supplied through the food, as the body cannot synthesize it. The other essential fatty acid is omega-6, found in corn, dairy products and soybean oil. Omega-3 and omega-6 have complementary functions. Omega-3 decreases inflammation and is an important component of cell membranes and nerve synapses. Omega-6 increases inflammation when there are foreign invaders in the body.

Omega-3 and Depression

As reported in Science Daily, a 2001 study completed in Finland showed that infrequent consumption of fish and depression were significantly correlated. A Dutch study published in 2003 showed that people who were depressed and those without depression had significantly different intakes of omega-3 fatty acids. In a newer study published in the June 2010 issue of "Journal of Clinical Psychiatry," it was found that omega-3 supplements were as efficient as conventional antidepressant medications in the treatment of major depression.

Serotonin in Anxiety and Depression

According to Joseph R. Hibbeln from the National Institute on Alcohol Abuse and Alcoholism, omega-3 can affect the functionality of the neurotransmitter serotonin, which plays a critical role in both depression and anxiety. Depression and anxiety have similar chemical profiles. Both disorders are characterized by low brain levels of serotonin. The most widely used antidepressant drugs, selective serotonin re-intake inhibitors, or SSRIs, work by slowing the speed with which serotonin outside the neurons is broken down and re-absorbed into the cells. These drugs are also commonly prescribed for anxiety disorders. If omega-3 fatty acids can help prevent depression by increasing the functionality of serotonin, it can also help prevent anxiety.

Synaptic Function

The 2011 study of the lack of dietary omega-3 suggests that it may help prevent mood disorders. Omega-3 is essential to the optimal function of two brain regions involved in motivation and emotional regulation -- the prefrontal cortex and the nucleus accumbens. As a lack of motivation is more significant in depression than in anxiety, suggesting that omega-3 may have a greater positive effect on depression than anxiety.

Fish Oil and Depression - Blog

The information in this blog has not been verified by your country's public health authority and is not intended as a diagnosis, treatment, or medical advice. Read more

What if, in treating depression, doctors stop manipulating brain chemistry with drugs and focus on maintaining that very chemistry? A new study on fish oil supplements from the University of Pittsburgh suggests that fewer college students may experience depression or need to take antidepressants

Depression is a big problem for college students. According to recent studies, 30% of students have experienced depression that makes life difficult for them, and 6% have seriously considered suicide during the previous 12 months. Given the relative ineffectiveness of prescribed antidepressants and the potential for adverse reactions to their use, it is important to help these young people with proper nutrition and supplementation. After all, you don't get depressed because you don't get enough Prozac or another antidepressant. But the fact that you are missing some important element, for example, long-chain fatty acids from fish oil, can be one of the main causes of depression.


Fish oil supplements, primarily long-chain omega-3 fatty acids EPA and DHA, which are free of lipid peroxides, heavy metals, environmental pollutants, and other harmful compounds, have revolutionized dietary science . A huge body of scientific evidence now shows that fish oil can prevent or help treat over 60 different conditions, including depression and other brain disorders.

Studies have also shown that countries with high fish oil consumption have low levels of depressive disorders.

The importance of omega-3 fatty acids for brain function is related to their role in the phospholipid composition of nerve cell membranes. Studies have shown that EPA and DHA affect:

  • The flexibility of brain cell membranes.
  • Synthesis of neurotransmitters.
  • Binding of neurotransmitters.
  • Activity of key enzymes that break down neurotransmitters such as serotonin, epinephrine, dopamine and norepinephrine.

Fish oil rich in EPA and DHA has been shown to have a positive effect on patients suffering from depression and bipolar disorder (manic depression) when consumed at recommended doses (eg 1000-3000 mg EPA + DHA). But these studies have mostly been done on older people who usually take antidepressants.

New Data:

To evaluate the effects of fish oil supplementation on depressed young people, a double-blind study was conducted in 23 patients (78% women) with a mean age of 20 years. These patients suffered from major depression, evidence of which was that they scored over 10 on a standard diagnostic questionnaire (the Beck Depression Inventory [BDI]). They were NOT taking antidepressants. Subjects were randomly assigned to placebo (corn oil) and fish oil (1. 4 g EPA + DHA [eicosapentaenoic and docosahexaenoic acids]). The BDI was completed before and on day 21 of supplementation.

The results showed a significant group difference in depression. Among patients treated with fish oil, 67% no longer met the criteria for depression, while in the placebo group, only 20% were no longer ill.


These results are very significant and show that a low dose of fish oil can produce very fast mood-enhancing results. Despite the impressive results, my recommended therapeutic dose of fish oil is 3000mg EPA+DHA. This dosage level could give even better results based on previous studies done with elderly patients.

In addition, over the past few years I have presented several newsletters highlighting research into nutrition that improves mood, brain health, memory, and/or prevents age-related mental decline. Here are the key areas of research: reducing inflammation, controlling blood sugar levels, providing essential elements through high-quality nutrition, and protecting the brain from damage through the consumption of antioxidants both in the diet and through supplements.

In terms of diet, the Mediterranean or New Nordic diets seem to be very beneficial. Speaking of supplements, in addition to fish oil, there are three other main recommendations:

#1. Take a high-quality multi-mineral supplement that provides at least the recommended daily allowance for all vitamins and minerals.

#2. Take enough of the vitamin (typically 2,000-5,000 IU daily) to raise your blood counts to the optimal range (50-80 ng/mL).

#3. Take additional plant-based antioxidants, such as flavonoid-rich extracts such as grape seed or pine bark, curcumin (Theracurmin), green smoothie, or resvera.


Ginty AT, Conklin SM. Short-term supplementation of acute long-chain omega-3 polyunsaturated fatty acids may alter depression status and decrease symptomology among young adults with depression: A preliminary randomized and placebo controlled trial. Psychiatry Res. 2015 Sep 30;229(1-2):485-9.

Share this article

Should I add fish oil to my diet to prevent depression?


Materials and methods
The results were published in the online journal of the American Medical Association.
The VITAL-DEP study included 18,353 elderly patients (mean age 67.5 years; 49% women).
Of these, 16,657 patients were at risk for depression, defined as no history of depression; and 1696 people were at risk of relapse of depression, which was defined as a history of depression, but the depression had not been treated for the past 2 years.
Approximately half of the participants were randomly assigned to omega-3 fatty acids (1 g/day of fish oil, including 465 mg of eicosapentaenoic acid [EPA] and 375 mg of docosahexaenoic acid [DHA]), and the other half were given placebo for an average of 5.3 years.
Due to the large sample size and long-term follow-up, it was possible to test the effect of daily omega-3 fish oil supplementation on universal prevention of depression in the adult population.


  • The results showed that the risk of depression or clinically significant depressive symptoms (total number of cases and relapses) did not differ significantly between the omega-3 group and the placebo group.

  • In the omega-3 group, there were 651 depressive events or clinically significant depressive symptoms (13.9 per 1000 person-years), and in the placebo group there were 583 cases of depression or clinically significant depressive symptoms (12.3 per 1000 person-years).

  • The hazard ratio was 1.13 (95% CI 1.01–1.26; P = 0.03).

  • There were also no significant differences between groups in longitudinal mood scores.

  • The mean difference in change in the 8-item patient health questionnaire (PHQ-8) score was 0.03 points (95% CI, -0.01 to 0.07; P = 0.19).

  • "Increasingly, omega-3 supplements are being found to be beneficial in preventing cardiovascular disease and treating inflammatory conditions, in addition to being used to treat existing depressive disorders in some high-risk patients," the authors say.

  • “However, the results of our study suggest that there is no reason for adults to take daily fish oil supplements solely for the purpose of preventing depression or maintaining a positive mood.

  • It is noted that the VITAL-DEP study used a dosage of 1 g/day of omega-3 fatty acids, and more benefit may be obtained from higher doses, such as 4 g/day.

  • Some limitations cited by the investigators are that depression or depressive symptoms were defined using self-report scales that are useful for screening for depressive disorders, but a high score on the self-report scale does not necessarily indicate the presence of depressive psychopathology.

  • Also, the use of 465mg EPA and 375mg DHA in VITAL-DEP "may be too low" to have a clinically meaningful impact.

  • According to the clinical guidelines of the International Society for Research in Nutritional Psychiatry, the recommended doses should be 1-2 g of pure EPA per day or from a combination of EPA/DHA.

  • It is also important to consider the potential Type I error, which makes secondary and subgroup analyzes less reliable.

    Learn more