Info Cart -

Omega 3 Fatty Acids and Mental Health

Summary: Omega-3 fatty acids are found in our food. They are essential to health and wellness. Studies show they may also be helpful in preventing and treating medical conditions that affect the brain, heart and other organs.


For healthy youth and adults, experts recommend eating fish (particularly fatty fish like salmon, mackerel, lake trout and sardines) at least two times per week (AHA, 2017) or to take 250 mg/day of omega-3 fatty acids as a supplement (USDA, 2010; WHO, 2008).


For youth and adults who suffer from depression or other mental health conditions, experts recommend taking 1,000-2,000 mg/day of EPA, one of the more common omega-3 fatty acids. (Peet, 2005; Bozzatello, 2016; CANMAT, 2016; Sarris, 2016).
Add to Info Cart
PDF
Image credit: Adobe Stock

What are omega-3 fatty acids?

Omega-3 fatty acids are fats found in the diet that are essential to the human body for:  
  • The brain (and nervous system). 
  • The skin, joints and soft tissues. 
  • The heart. 
There are three different types of omega-3 fatty acids:
  • EPA (eicosapentaenoic acid) - decreases inflammation in the body. It is important for general health. 
  • DHA (docosahexaenoic acid) - helps our cells communicate with each other. It is an important omega-3 fatty acid for the brain, eyes and heart. 
  • ALA (alpha-linolenic acid) - used by the body as energy. Taking DHA and/or EPA is usually recommended over taking ALA.  
In past centuries, omega-3 fatty acids were high in our diet. Many changes in modern society now make it difficult for the average North American child or adult to consume enough omega 3-fatty acids to provide health benefits (Papanikolaou, 2014). This may be a factor in the increase we have seen in the past century in certain medical, like heart disease and diabetes.

What are the symptoms of a diet low in omega-3? 

Most of the time, people who have a diet low in omega-3 will not have any signs or symptoms.
 
Nonetheless, symptoms that can be seen include:
  • Physical symptoms: excessive thirst, frequent urination, rough or dry ‘bumpy’ skin, dry, dull or ‘lifeless’ hair, dandruff and soft or brittle nails. 
  • Allergy symptoms: eczema, asthma, hay fever. 
  • Visual symptoms: poor night vision, sensitivity to bright light or visual disturbances when reading.
  • Attention/concentration problems: distractibility, poor concentration or difficulties with memory.
  • Mood problems: depression, mood swings or anxiety. 
  • Sleep problems: especially difficulty settling at night or waking in the morning.
If you have any of the above, it is possible that this could be from a low diet in omega-3 fatty acids. You should consult your family physician for more information, since you may benefit from taking an omega-3 supplement. 

I think I may be low in omega-3… What should I do?

See your primary care provider (e.g. family doctor) to see if you might be low in omega-3 fatty acids. Your doctor can see you, and if appropriate, recommend an omega-3 supplement at the right dose for your symptoms. 

What is the evidence that omega-3 is helpful in mental health?

In 2016, the Canadian Network for Mood and Anxiety Treatments (CANMAT) published a review of complementary/alternative health medicines for the treatment of mental health disorders in the Canadian Journal of Psychiatry. Use of omega-3 fatty acids was found by CANMAT to be helpful when added to other treatments for some mental health disorders like depression. 
 
A major review in the American Journal of Psychiatry (Sarris, 2016) also showed supplementation with omega-3 fatty acids was helpful to patients suffering from mood disorders. 

How much omega-3 is recommended?

The following table provides the recommended dosage of omega-3 in various mental health disorders: 
 

Condition

Dosage daily 

References

Depression in youth/adults 

1,000-2,000 mg EPA

Bozzatello, 2016

CANMAT, 2016

Sarris, 2016

ADHD in children/youth 

 

 

●      Patients 16-25 kg 

500 mg EPA 

Belanger, 2009

●      Patients 26-35 kg 

750 mg EPA 

Belanger, 2009

●      Patients 36-45 kg 

1,000 mg EPA 

Belanger, 2009

ADHD Study with EPA/DHA 

 

 

●      Boys aged 8-14          

650 mg EPA / DHA 

Bos, 2015 

Schizophrenia

Not recommended due to insufficient data

Bozzatello, 2016

Bipolar Disorder as add-on therapy

1,000-2,000 mg EPA 

Bozzatello, 2016

Anxiety

Not recommended due to insufficient data

Bozzatello, 2016

 
In Canada, one of the challenges with herbal and alternative medicines, including omega-3 fatty acids, is that, unlike medications, there is no organization overseeing their production to make sure that they are safe, effective or contain the medicines claimed on the label. So, it is important to purchase these medicines from a reputable retailer, like your community pharmacy, and to consult an expert health care professional, including your family physician, nurse practitioner, pharmacist or dietitian. 

I don’t want to take supplements… What about just eating more fish?

For healthy youth and adults, the American Heart Association recommends eating fish two times per week for the prevention of heart disease. There is no information to support taking omega-3 fatty acids to prevent heart disease or diabetes (AHA, 2017).
 
For the treatment of mental health disorders, including depression and ADHD, most experts feel its probably better to get most of your omega-3 fatty acids from a supplement. The problem with eating enough fish for omega 3-fatty acids is that many fish sources also contain mercury. To get enough omega 3 fatty acids, one could be exposed to dangerous levels of mercury. The good news about fish supplements is they do not contain mercury. (McNamara, 2013)
 
If you do eat fish, the Environmental Working Group provides regularly updated information on mercury content of various fish and seafood sources:
http://www.ewg.org/research/ewg-s-consumer-guide-seafood/seafood-calculator

I don’t like fish or fish oil… What about flaxseed oil?

For the healthy person looking to increase their intake of omega-3, it makes sense to eat more flaxseed oil.
 
However, for individuals with brain or heart conditions, the studies published to date are mainly on omega-3 from fish oil. Flaxseed oil is primarily made up of ALA. Alternatively, fish oil is made up of EPA and DHA, shown to be more beneficial at this time than ALA.  

What about omega-6 and omega-9 fatty acids?

Two other important fatty acids are: 
  • Omega-6 fatty acids are important to our cells and our immunity. In excess, they can cause inflammation and inflammatory disease.
  • Omega-9 fatty acids (e.g., oleic acid) are the most common monounsaturated fat in our diet. This fatty acid is important to control high cholesterol.
Although the human body cannot make its own fatty acids, there is a maximum amount it can use. Omega-3 and omega-6 fatty acids compete for space in the body.
 
Because omega-3 fatty acids reduce inflammation in the body and, at high doses, omega-6 fatty acids cause inflammation, it is important to increase the quantity of omega-3 in the body than omega-6 fatty acids.
 
Unfortunately, omega-6 fatty acids are much more common in the diet than omega-3 fatty acids.
 
To get the best out of taking omega-3 fatty acids, it is important to reduce the intake of omega-6 fatty acids in our diet (Husted, 2016).
 
The recommended ratio is 4:1 for omega-6 to omega-3 in our diet or better (lower omega-6 and higher omega-3).

How can I change my diet to improve health and wellness?

Increase Omega-3 
  • Take supplement recommended by a health care professional, like your doctor or pharmacist.
  • Eat fish and seafood.  
Decrease Omega-6
  • Avoiding cooking with seed oils (e.g., corn, sunflower, canola, sesame, soybean).
  • Reducing (ideally stopping) your consumption of fried foods (french fries, chips).
  • Reducing your intake of dark meat from poultry (chicken and turkey).
  • Reading labels on packaged food to avoid those made with seed oils.
  • Eating home-cooked foods.

Any side effects from omega-3 fatty acids?

Omega-3 fatty acids (EPA/DHA combination products) are generally safe and well tolerated. However, they are associated with a few minor side effects, including nausea, fishy aftertaste in the mouth and an increase in low-density lipoprotein (LDL) cholesterol at high doses (greater than 4 g/day of EPA). (Bozzatello, 2016) 

References

Bélanger SA et al.: Omega-3 fatty acid treatment of children with attention-deficit hyperactivity disorder: A randomized, double-blind, placebo-controlled study. Paediatr Child Health. 2009 Feb;14(2):89-98.
https://www.ncbi.nlm.nih.gov/pubmed/19436468 
 
Bos DJ et al.: Reduced Symptoms of Inattention after Dietary Omega-3 Fatty Acid Supplementation in Boys with and without Attention Deficit/Hyperactivity Disorder. Neuropsychopharmacology 2015 volume 40, pages 2298–2306.
https://www.nature.com/articles/npp201573 
 
Chang CH et al.: Safety and tolerability of prescription omega-3 fatty acids: A systematic
review and meta-analysis of randomized controlled trials. Prostaglandins Leukot Essent Fatty Acids. 2018 Feb;129:1-12. 
https://www.ncbi.nlm.nih.gov/pubmed/29482765# 
 
Freeman MP, et al. Freeman MP, Hibbeln J, Wisner KL, et al. Omega-3 fatty acids: evidence basis for treatment and future research in psychiatry. J Clin Psychiatry. 2006;67(12):1954-1967.
 
Gracious BL, et al. Randomized, placebo-controlled trial of flax oil in pediatric bipolar disorder. Bipolar Disord. 2010 Mar;12(2):142-54.
 
Grosso G, et al. Dietary n-3 PUFA, fish consumption and depression: A systematic review and meta-analysis of observational studies. J Affect Disord. 2016 Nov 15;205:269-281.
 
Husted KS, et al. The importance of n-6/n-3 fatty acids ratio in the major depressive disorder. Medicina (Kaunas). 2016;52(3):139-47.
 
Jacka F, et al. A randomised controlled trial of dietary improvement for adults with major depression (the 'SMILES' trial). BMC Med. 2017 Jan 30;15(1):23.
 
Kris-Etheron PM, Harris WS, Appel LJ, for the AHA Nutrition Committee. Omega-3 fatty acids and cardiovascular disease. New recommendations from the American Heart Association (editorial). Arterioscler Thromb Vasc Biol 2003;23:151–2.
 
Messamore E, et al. Polyunsaturated fatty acids and recurrent mood disorders: Phenomenology, mechanisms, and clinical application. Prog Lipid Res. 2017 Jan 6;66:1-13.
 
Nemets H, Nemets B, Apter A, Bracha Z, Belmaker RH: Omega-3 treatment of childhood depression: a controlled, double-blind pilot study. Am. J. Psychiatr 2006 Jun; 163(6): 1098-1000. 
 
Peet M, Horrobin DF: A dose-ranging study of the effects of ethyl-eicosapentaenoate in patients with ongoing depression despite apparently adequate treatment with standard drugs. Arch Gen Psychiatry. 2002 Oct; 59(10):913-9. Treatment with EPA at 1 g/day was effective in treating depression in patients who remained depressed despite adequate standard therapy. Note that 1 g/day was effective and that increasing dosages (such as 2-g and 4-g daily) were not effective.
 
Parker G, Gibson A, Brotchie H, Heruc G et al.: omega-3 fatty acids and mood disorders, Am. J. Psychiatr Jun 2006; 163;6, p.969. 
 
Peet M, Stokes C: Omega-3 fatty acids in the treatment of psychiatric disorders. Drugs. 2005;65*8): 1051-9. 
https://www.ncbi.nlm.nih.gov/pubmed/15907142 
 
Ravindran AV, et al. Canadian Network for Mood and Anxiety Treatments (CANMAT) 2016 Clinical Guidelines for the Management of Adults with Major Depressive Disorder: Section 5. Complementary and Alternative Medicine Treatments. Can J Psychiatry. 2016 Sep;61(9):576-87.
 
Sarris J, et al. Adjunctive Nutraceuticals for Depression: A Systematic Review and Meta-Analyses. Am J Psychiatry. 2016 Jun 1;173(6):575-87.
 
Sin N. Physical fatty acid deficiency signs in children with ADHD symptoms. Prostaglandins Leukot Essent Fatty Acids. 2007 Aug;77(2):109-15.
 
U.S. Department of Health and Human Services, U.S. Department of Agriculture. Dietary Guidelines Advisory Committee Meeting. Meeting Summary. Jan. 28, 2004:34. 
http://www.health.gov/dietaryguidelines/dga2005/ dgac012004minutes.pdf 

Further Readings 

Logan A: Omega-3 fatty acids and major depression: A primer for the mental health professional, Lipids in Health and Disease 2004 3:25. 
http://www.lipidworld.com/content/3/1/25  
 
Omega-3 fatty acids, from the University of Maryland
www.umm.edu/altmed/ConsSupplements/Omega3FattyAcidscs.html

Acknowledgements

Written by Alan C. Logan (ND), Michael Cheng (Psychiatrist), Kristian Goulet, paediatrician, Renée St-Jean, pharmacist. 

Creative Commons License

This work is “licensed” under a Creative Commons License (Attribution-Non Commercial- Sharelike 2.0, http://creativecommons.org/licenses/by-nc-sa/2.0/) which means that you are free to  copy, distribute, display and perform the work, and make derivative works as long as you give the original author credit; the work is not used for commercial purposes; and if you alter, transform, or build upon this work, you may distribute the resulting work only under a license identical to this one.

Disclaimer

The content of this document is for general information and education only. No doctor/patient relationship is formed. The accuracy, completeness, adequacy, or currency of the content is not warranted or guaranteed. The content is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Users should always seek the advice of physicians or other qualified health providers with any questions regarding a health condition. Any procedure or practice described here should be applied by a health professional under appropriate supervision in accordance with professional standards of care used with regard to the unique circumstances that apply in each practice situation. The author(s) disclaim any liability, loss, injury, or damage incurred as a consequence, directly or indirectly, or the use and application of any of the contents of this document.
Date Posted: Apr 25, 2018
Date of Last Revision: Jul 12, 2018

Was the information on this page helpful?