Medically reviewed by Timothy J. Legg, Ph.D., CRNP — Written by Diana Wells 
Updated on September 18, 2018

Overview

Omega-3 fatty acids are incredibly important for their many functions within the body. It’s been studied thoroughly for its effects on heart health and inflammation — and even mental health.

So what do we know? For over 10 years, researchers have been studying the effects omega-3 may have on depression, as well as other mental and behavioral conditions. Although the research is fairly recent, and more needs to be done before final conclusions can be made, it’s been promising. Most studies are showing that omega-3s may be helpful in treating some forms of depression.

Keep reading to learn more about the research and omega-3’s benefits and side effects.

Fish oil

There are three main types of omega-3s in the diet, and two are found in fish oil: DHA (docosahexaenoic acid) and EPA (eicosapentaenoic acid). You can get fish oil by including fish in your diet or through a supplement.

Including fish oil and omega-3s as part of a healthy diet has been shown to improve or, in some cases, prevent several health conditions, including heart disease, rheumatoid arthritis, and high cholesterol. Other conditions are being researched and look like they may also be helped with omega-3 and fish oil. These include ADHD as well as some forms of cancer.

It’s good to note that fish oil and cod liver oil aren’t the same thing. Fish oil doesn’t contain other vitamins like D and A.

What the research says about omega-3s and depression
Your brain needs the type of fatty acids that are in omega-3s for proper functioning. It’s believed by some that those who experience depression may not have enough EPA and DHA. This is the premise that researchers are using as they study the possible benefits of using omega-3 and fish oil to treat depression.

In 2009, researchers reviewed data from three studies that used EPA in the treatment of three different types of depression: recurrent major depression in adults, major depression in children, and bipolar depression. The large majority of subjects taking EPA in all types showed significant improvement and benefited from the EPA as compared to those with a placebo.

An overview of research from 2004 on omega-3s and depression showed that DHA may also play an important role along with EPA in the treatment of various types of depression. Those with minor depression, postpartum depression, and suicidal ideation had lower levels of EPA and DHA. These studies showed that a combination of EPA and DHA found in fish oil seemed to improve the depression symptoms of most participants that were tested.

As a whole, the research done up to this point seems positive for the use of fish oil and omega-3s in the treatment and management of depression. However, most studies acknowledge the need for larger studies and continued research on the subject.