As of April 2021, the only proven efficacy and effect of fish oil is to lower triglycerides.

Contraindications:

People to watch out for

Liver disease (increased bleeding), fish and seafood allergies, AIDS, high doses of fish oil may lower immune response (people with already weakened immune systems should be wary of this), diabetes (high doses of fish oil may interfere with blood sugar smoothing), and high blood pressure (individuals on blood pressure lowering medication may individually have too low blood pressure).

Extended information:

Eating fish oil is actually the equivalent of eating fish fat, which is unsaturated fatty acids. Eating too much greasy food, saturated fatty acids will be deposited in the body's large blood vessels, in certain circumstances to form atherosclerosis. And proper consumption of unsaturated fatty acids can promote the metabolism of saturated fatty acids in the body, to a certain extent, can prevent or reduce the occurrence or development of atherosclerosis.

Theoretically, omega-3 polyunsaturated fatty acids, which are rich in fish oil, are components of the brain and retina. Fish oil does have a certain role in improving memory and protecting the retina, but there are not many studies on fish oil's ability to prevent Alzheimer's disease and brighten eyes, and the evidence is not yet sufficient.

Baidu Encyclopedia - Fish Oil

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