Fish Oil

Last Updated: September 28, 2022

Fish oil is a source of omega-3 fatty acids. It reduces triglycerides, but does not seem to affect the rate of cardiovascular events. It seems to notably reduce the symptoms of depression and improve some painful, inflammatory conditions.

Fish Oil is most often used for

What is fish oil?

Fish oil is a common term used to refer to two kinds of omega-3 fatty acids: eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). These omega-3 fats are usually found in fish, animal products, and phytoplankton.

The fatty acids EPA and DHA are involved in regulating various biological processes such as the inflammatory response, various metabolic signaling pathways, and brain function.[1] They can be synthesized in the body from alpha-linolenic acid (ALA), but in small amounts for most people.

What are fish oil’s main benefits?

Fish oil causes a potent reduction in triglyceride levels,[2][3][3][4][5][6][7][8][9][10][11][12] and a more modest reduction in blood pressure in hypertensives.[4][12][13][14][15][16][17][18] Despite this, long-term trials haven't found a reduction in the rate of cardiovascular events.[19]

It appears to notably improve mood in people with major depression, though it's unclear if it has an effect in people with minor depression.[20] EPA, in particular, seems to be the most effective omega-3 fatty acid for this purpose which suggests that the effects of fish oil are due to reducing neuroinflammation. Its anti-inflammatory benefits also seem to extend to reducing the symptoms of systemic lupus erythematosus.[21][8][22][22][23][24][25] However, its benefits shouldn't be assumed to extend to inflammatory diseases in general.

What are fish oil’s main drawbacks?

Many fish oil supplements may contain harmful lipid peroxides (oxidized lipids that can damage cells), but it's unclear if this has notable consequences to health.[26]

How does fish oil work?

Fish oil reduces fasting triglycerides by reducing the amount of triglyceride-rich VLDL production done by the liver. It also reduces post-meal triglycerides by boosting the rate at which triglyceride-rich chylomicrons are removed.[27] Fish oil may reduce blood pressure by increasing nitric oxide availability and relaxing smooth muscle.[28] It also has anti-inflammatory effects partially due to its ability to affect the shifting balance between inflammatory and anti-inflammatory signaling, which, in turn, affects cell membranes.[29]

What else is Fish Oil known as?
Note that Fish Oil is also known as:
  • Eicosapentaenoic Acid
  • EPA
  • Docosahexaenoic Acid
  • DHA
  • Omega-3 fatty acids
  • Omega-3
  • Omega 3
  • N-3 Fatty Acids
Fish Oil should not be confused with:
  • Alpha-Linolenic Acid (the plant-based omega-3)
Dosage information

Fish oil doses vary depending on the goal of supplementation. For general health, 250mg of combined EPA and DHA is the minimum dose and can be obtained via fish intake. The American Heart Association recommends 1g daily.

Since fish oil is a combination of two different fatty acids, these numbers reflect a combined total. Total eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) consumption should come from a mix of real food and supplements. The more EPA and DHA is provided by the diet, the less supplementation is required.

Fish oil can be taken throughout the day. To minimize the "fish burp" taste, take fish oil with meals.

Pregnant women should increase their intake of DHA by at least 200mg a day, as long as there is no risk of elevated mercury levels.

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Examine Database: Fish Oil