Is Fish Oil an Antidepressant?

Fish oil is a good source of omega-3 fatty acids, which play an essential role in your brain’s functions. There have been studies that show omega-3 fatty acids may help treat depression in some people.

Fish oil is a good source of omega-3 fatty acids, which play an essential role in your brain’s functions. There have been studies that show omega-3 fatty acids may help treat depression in some people. In countries where people eat a lot of fish, depression is not as common as it is in other countries.

Fish oil is full of omega-3 fatty acids, which are important for brain function, growth and development, and reducing inflammation. Docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) are types of omega-3 fatty acids that are found naturally in fish. Another type, alpha-linolenic acid (ALA), is found in plant foods and converted to DHA and EPA in your body. You can't make omega-3 fatty acids, so you have to get them from your diet.

Not getting enough omega-3 fatty acid has been linked to:

• Heart disease
• Cancer
• Mood disorders

More research is needed to figure out if and how fish oil affects symptoms of depression. People who have major depressive disorder tend to have more inflammation in their bodies than people who don't have a major depressive disorder. One theory is that fish oil helps by reducing inflammation.

Another theory is that the omega-3 fatty acids can move through the cell membranes in your brain and interact with the molecules in your brain cells that affect your mood. The fatty acids DHA and EPA are the ones that seem to be most effective.  

A small study of 22 people who were given either 3 grams of EPA or 1.4 grams of DHA daily for 12 weeks found that they had a significant improvement in their depressive symptoms. Both groups had increased levels of fatty acids in their blood. The EPA group reported a 64 percent reduction in their symptoms, and the DHA group reported a 71 percent reduction in their symptoms. Since this was such a small study, more research is needed in this area.

In addition to possibly helping with depression, fish oil may help prevent psychotic disorders in people who are at risk for developing them. One study of 81 people who were at ultra-high risk for developing psychotic disorders found that those who were given omega-3 fatty acids were less likely to develop a psychotic disorder and were able to function better.

Another study of children and adolescents with juvenile bipolar disorder who were given 360 milligrams of EPA and 1560 milligrams of DHA showed fewer episodes of mania and depression. They also had increased global functioning, which is a measure of how well a person functions in their daily life.

More research is needed, but omega-3 fatty acids may also provide relief for people who suffer from other types of mood disorders, such as:

• Postpartum depression
• Schizophrenia
• Borderline personality disorder
• Obsessive-compulsive disorder
• Attention deficit disorder

Researchers don't fully understand how food affects the body. It may be that the omega-3 fatty acids only work with all of the other fats, vitamins, and minerals present in fish. Unless you have a deficiency, supplements may not be the best way to get your nutrients. You're likely better off eating foods that are naturally high in omega-3 fatty acids than buying supplements.

Foods that are high in DHA and EPA include:

• Salmon
• Tuna
• Trout
• Mussels
• Oysters
• Cod
• Fish eggs
• Pickled herring
• Clams
• Snow crab

Plant foods that are high in ALA include:

• Walnuts
• Flaxseeds
• Chia seeds
• Hemp seeds
• Edamame
• Seaweed
• Algae

When you get omega-3 from your diet, it's usually safe. If you're getting it from fish, you should make sure you're not eating fish that has been contaminated with mercury.

Fish oil supplements may cause the following side effects:

• Heartburn
• Nausea
• Diarrhea
• Fishy aftertaste
• Bad breath
• Rash

High doses of fish oil may increase your risk of bleeding or stroke. It can also interact with some medications, so talk to your doctor before you start taking fish oil supplements.