Definition of fish oils

Fish oil comes from various species of oily fish, such as mackerel, tuna, and herring. Manufacturers can use many different methods to harvest fish oil, but most techniques typically involve a four-stage process that includes cooking, pressing, filtering, and centrifuging the resultant oil.

Fish oils contain omega-3 polyunsaturated fatty acids. These are essential fatty acids that the body cannot make itself. Two of the most well-known types of omega-3 are eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA).

Consuming fish oils and omega-3 may bring some health benefits and help with a number of health conditions.

List of possible benefits

Fish oil may have an impact on different areas of health and be a useful supplement for many people. The following is a list of some potential benefits of fish oil for men.

Sexual health and fertility

Although not widely reported, fish oil supplements may have benefits for sexual health and fertility.

A 2017 animal study examined the effects of omega-3 fatty acids and erectile dysfunction due to atherosclerosis. In this condition, the blood vessels narrow, which can affect erections. Rats in the treatment group fed omega-3 fatty acids demonstrated significantly improved erection quality.

It is essential to bear in mind that animal studies do not indicate the same results in humans. However, an earlier review also indicates that omega-3 could help men with erectile function.

In a 2020 study of 1,694 young male participants, those who reported using fish oil supplements had larger testes and higher semen volume and quality.

They also had a healthier-looking profile of follicle-stimulating hormone and luteinizing hormone. These are two key hormones that regulate sperm production.

Although the study cannot conclude that the fish oil is causing the improvement, it suggests that it may play a role.

Mental health

Research suggests that individuals with depression may have lower blood levels of omega-3 fatty acids. In a small study of 23 people published in Psychiatry Research, supplementation with omega-3s helped improve symptoms of depression within 3 weeks.

There are links between depression and memory problems. Supplementing with DHA alone or in combination with EPA may improve memory function in some groups of adults.

While studies suggest that omega-3 supplementation may help prevent cognitive decline, especially in older adults, a 2019 review notes that more research is still necessary.

Heart health

Heart disease accounts for 1 in 4 deaths in the United States each year. According to the Centers for Disease Control and Prevention (CDC), heart disease is the leading cause of death for men in the U.S.

Eating fish may have a protective effect on heart health by reducing some of the risk factors for heart disease.

Triglycerides are a type of fat found in the blood, and although the body needs them, if levels are too high, they can increase the risk of heart disease.

Fish oil may help lower elevated triglyceride levels and blood pressure. Eating fish may also help to significantly lower low-density lipoprotein or “bad” cholesterol.

While many sources promote the potential benefits of fish oil for cardiovascular health, clinical studies do not consistently support them. For example, an analysis published in JAMA Cardiology could not find a clear link between fish oil and lower heart disease risk.

Eye health

Some evidence suggests that an adequate intake of fish oil may help protect eye health. A 2017 review notes that fish oil may play a role in the treatment of inflammatory eye diseases such as age-related macular degeneration (AMD) and dry eye disease.

A 2019 study indicates that people who regularly consume fresh fruits, vegetables, and fish were less likely to develop AMD compared with those who did not.

The American Academy of Ophthalmology (AAO) recommend fish oils to reduce the symptoms of dry eye. However, some evidence suggests they have no effect. A 2018 study found no evidence to indicate that taking fish oil supplements was more helpful than taking a placebo for dry eye.

Optometrists may recommend taking omega-3 supplements or increasing dietary fish consumption to benefit eye health, even though some scientific evidence suggests fish oils are not suitable for this purpose.

Risks and considerations

Before deciding to supplement their diets with fish oils, people should also consider the possible risks.

While some research indicates that eating a diet rich in omega-3 may help prevent prostate cancer, other research suggests otherwise. A 2013 study notes that a high fish oil intake may actually increase the risk of high-grade prostate cancer.

The National Institutes of Health (NIH) note that the link between omega-3 and different types of cancer, such as prostate, currently remains unclear.

Some people may experience mild side effects if they supplement with fish oil. These may include unpleasant taste, bad breath, diarrhea, flatulence, nausea, and other digestive symptoms.

How to increase your omega-3 level

The three primary omega-3 fatty acids are EPA, DHA, and alpha-linolenic acid (ALA). While the first two are present in fish oil, ALA comes from plant oils such as flaxseed, soybean, and canola oils.

ALA is an essential fatty acid, meaning that the body cannot make it, and it must come from a dietary source. Although the body can convert small amounts of ALA into EPA and then to DHA, the most practical way to increase these omega-3 fatty acids is from food or a nutritional supplement.

ALA is the only omega-3 that is essential, so it is the only one with a recommended adequate intake. Research suggests that males should aim for roughly 1.6 grams.

Both EPA and DHA do not have official recommended daily dosages as they are not essential nutrients. However, the British Dietetic Association suggest a daily dose of about 450 mg EPA and DHA for adults.

It can be difficult to judge the intake from nutritional supplements, as the amounts of fish oil may vary. For example, 1,000 mg of fish oil from one brand of supplement may contain less or more EPA and DHA than the same amount of oil from another brand.

People can get enough omega-3 by including the following foods in their diet:

• fish and seafood, especially sardines, tuna, mackerel, salmon, and herring
• nuts and seeds such as chia seeds and walnuts
• plant oils such as flaxseed, soybean, and canola oil
• fortified foods such as some types of eggs, yogurt, and soy beverages

Alternatively, people may benefit from a fish or vegetarian algae oil supplement to boost levels. Some evidence suggests that taking a fish oil supplement with a meal that contains fat may help to increase absorption.

Summary

Fish oil is rich in omega-3, which is an essential nutrient. Eating a diet containing oily fish, or taking a fish oil supplement, can ensure someone has an adequate amount.

Consuming more fish oil and omega-3 may offer some health benefits for men. This may include increasing fertility and improving heart health. However, men should weigh up the benefits with a potential increased risk of prostate cancer.

Anyone who is considering taking supplements should first check with a healthcare provider to ensure that it is safe.