The Truth About Fish Oil: Proven Benefits, Dosage, Side Effects

Our bodies require nutrients for its many functions. Apart from minerals and vitamins we also need certain fatty acids for healthy living. Omega-3 fatty acids from fish oil are needed for normal growth and development, brain functions and inflammation. A lack of this important nutrient may cause health problems like mood disorders, arthritis, heart issues and more.

Omega-3 fatty acids are acquired from plants and marine sources. Flax seeds, walnuts, and canola oil are good sources of fatty acids. However, the form of fatty acids found in plants has to be converted to another to be absorbed by the body.

There are 11 important fatty acids in fish oil and 3 of them are more significant than others for health benefits. Fish oil is derived from the tissue of oily fish like sardines, mackerel, and anchovy. The majority of fish oil supplements come in the capsule form.

Let’s look at how fish oil has been used to improve health and treat many medical conditions.

Why Take Fish Oil?

Fish oil

Fish oil is a great source of fatty acids that are vital for the production of energy. The body needs fatty acids for its functions and the health benefits of fatty acids are varied. Fish oil contains omega-3 fatty acids that protect the heart. Our requirement for this fatty acid has to be met from our diet as the body does not produce them. Vitamin A and vitamin D are also derived from some fish oils that are vital for immunity and bone health.

The benefits of Omega-3 fatty acids for neuro disorders and brain health are backed by clinical trial evidence. There are two main omega-3 fatty acids present in fish oil. They are eicosapentaenoic (EPA) acid and docosahexaenoic acid (DHA). The clinical tests of EPA have reported favorable effects while DHA has been found to be helpful in neurodegenerative conditions like Alzheimer’s disease. Now substantial investigations have shown shared benefits of both EPA and DHA.

The Dietary Guidelines for Americans (2015 to 2020) recommend that the general population should take approximately 8 ounces of different kinds of seafood each week. It is estimated to provide 25mg EPA and DHA per day. For pregnant and nursing mothers the suggestion is to take 8 to 12 ounces of seafood per week. Regular intake of fish oil provides sufficient amounts of EPA and DHA. An irregular diet of fish will cause fewer amounts of EPA and DHA levels in the body.

Other sources of Omega-3 are found in flaxseed canola, walnuts, and soybeans. These plant sources do not have adequate amounts of EPA and DHA in them. The diet of most western countries has a rich content of omega-6 compared to omega-3. The high amount of omega-6 accompanied by an equally high ratio with omega-3 acids increases the vulnerability to many diseases like cardiovascular diseases, cancer, inflammatory and autoimmune diseases.

Diet rich in omega-3 with a low ratio of omega-6/omega-3 will inhibit the progress of such diseases. The risk of breast cancer was traced to a low ratio of these fatty acids. Repressed inflammation in patients suffering from rheumatoid arthritis was due to a ratio of 2-3/1. It is suggested that a dose of omega-3 fatty acids is dependent on the severity of the disease. Supplementation of fish oil will greatly enhance healthy living.

The increase in the consumption of omega-6 has been associated with obesity; the ratio of omega-6/omega-3 being as high as 20:1. It causes high levels of red blood cell membrane phospholipids while high omega-3 results in low RBC membrane phospholipids and reduces the risk of obesity. A balanced diet of omega-6/omega-3 is essential for bodyweight management.

What are the Benefits of Fish Oil?

Fish Oil Reduces Triglycerides

Hyperlipidemia is the medical condition where fats (lipids) in the blood are abnormally high. Triglycerides are a type of fat found in your blood and higher than optimum levels of triglycerides are known to cause stroke and heart disease.

High levels of triglycerides can also increase the risks of type-2 diabetes and inflammation of the pancreas. Fish oil is widely accounted for reducing hyperlipidemia.

A systematic search on records and documentation, review articles and conference abstracts along with placebo-controlled randomized trials were conducted to evaluate the outcome of the use of EPA/DHA supplements. 47 studies wherein the participants were not treated for hyperlipidemia were given 3.25 g of EPA and/or DHA. There was a clinical noteworthy reduction of TG.

The American Heart Association (AHA) has acknowledged omega-3 fatty acids as a safe and effective way to reduce triglycerides. According to the AHA, Omega-3 fatty acid supplementation “at a dose of 4 g/d, are clinically useful for reducing triglycerides, after any underlying causes are addressed and diet and lifestyle strategies are implemented, either as monotherapy or as an adjunct to other triglyceride-lowering therapies

Summary: Fish oil supplements containing EPA and DHA fatty acids have been found to reduce triglyceride levels in the blood.

Fatty Acid Composition May Improve Mood Disorders

Improve Mood

Research shows that fatty acids help alleviate depression. It is emerging as an effective therapy for mood imbalance. It was supposed that polyunsaturated fatty acids had a direct relation with mood regulation.

The study examined 3884 adults who were 60 years of age or above in a community-dwelling to note if there existed a difference in fatty acid composition among depressed and nondepressed subjects. Those who showed marked differences undertook a psychiatric interview to identify depressive disorders.

All suitable subjects had their plasma phospholipid concentrations measured. PUFAs percentage of 264 participants with depressive symptoms with 106 volunteers who had depressive disorders and 461 randomly selected reference subjects. The fatty acid composition of depressed subjects was different from that of the control subjects. The study concluded that fatty acid composition is associated with depression in community-dwelling people.

There have been many other studies that have proven omega-3 supplementation is effective for helping treat depression in both adults and children. Fish oil is a rich source of omega-3 fatty acids and thus its regular consumption may help keep depression at bay.

Summary: Studies have noted a marked difference in the fatty acid composition between depressed and nondepressed subjects in a community-dwelling. It has been found that omega-3 fatty acid supplementation may help reduce symptoms of depression.

Fish Oil May Improve ADHD Symptoms

Attention deficit hyperactivity disorder (ADHD) is the inability of sustained concentration and attention to tasks. It affects at least 3 to 7% of children. This neurological condition has been found to occur more in boys than in girls. 60 to 80% of the children with this disorder may have the problem even when they become adults.

A study on the effects of EPA and DHA on the behavior of children who had ADHD was published in Nutrition Journal in July of 2007. The study involved nine children who were first given 16.2 grams of EPA/DHA per day. The dosage was adjusted to match the levels found in the Japanese population depending on the ratio of arachidonic acid (AA) to EPA in the isolated plasma phospholipids.

At the end of 8 weeks levels of EPA and DHA have substantially increased while a distinct reduction in the AA: EPA ratio was also noted. A psychiatrist unaware of the supplement dosage reported remarkable changes in the behavior of the children. There was also a noted relation between the reduced AA: EPA ratio and the global scores on the severity of this illness. The study strongly suggested that a high dose of EPA/DHA concentrates may improve the behavior in children with ADHD.

Summary: Sufficient quantities of EPA and DHA positively influence the behavior outcome of children affected with attention deficit hyperactivity disorder.

Fish Oil Treatment For APS Causing Recurrent Miscarriage

Antiphospholipid syndrome (APS) also called Hughes syndrome at times is an immune system disorder wherein blood clots increase. This condition leads to deep vein thrombosis (DVT) that grows in the leg.

In 1989 22 women who had this condition and suffered recurrent miscarriage were given fish oil equivalent to 5.1 g EPA and DHA at the ratio of 1.5 EPA to DHA. Over a period of 3 years, all of them had pregnancies with one woman who had 2 pregnancies. There was only one intrauterine fetal death that was linked to pre-eclampsia (pregnancy complication of high blood pressure and signs of damage to other organs). Cesarean was conducted only on two women and all the babies did well. The birth weight of all the babies was above 2500 grams.

This pilot study was an encouragement to consider the use of fish oil as a preventive treatment in recurrent miscarriages.

Summary: Trials have indicated that adequate intake of fish oil reduces risks of miscarriage.

Fish Oil May Reduce Symptoms Of Schizophrenia

Schizophrenia is a mental disorder that is characterized by a disconnect between thoughts, emotions, and behavior. This leads to wrong understanding, uncoordinated feelings, and actions, withdrawal into a fantasy with a disoriented mindset.

Studies have indicated an association between the lack of vital fatty acids in patients suffering from this condition and healthy control subjects. Evidence has clearly pointed out the abnormality in membrane phospholipid in schizophrenic patients.

Another disorder that causes involuntary movement of the jaw and face which is called tardive dyskinesia suggests a lack of essential fatty acids.

A pilot study in the 90s has noted that sufficient supplementation of the 3 fatty acids has reduced symptoms of schizophrenia and tardive dyskinesia.

Summary: Fatty acids may reduce the symptoms of mental disorders like schizophrenia and also tardive dyskinesia which is a neurological disorder.

Fish Oil May Reduce Postpartum Depression

Fish oil is a rich source of omega-3 fatty acids especially EPA and DHA. These fatty acids are components of breast milk that amounts to 0.2% and 0.3% in Western countries. This quantity is adequate for the DHA needs of term breastfed infants however it is not so for preterm infants. Here maternal supplementation will increase DHA and EPA content.

Long-term intake is necessary for preterm infants to benefit from maternal supplementation. The current dietary recommendations for nursing mothers are 250 to 375 mg DHA and EPA daily. Lactating mothers require a daily dosage of 1000 mg DHA plus EPA.

Omega-3 fatty acids supplements have shown to affect postpartum depression in nursing mothers. 35 randomized controlled trials women diagnosed with severe depression benefitted from omega -3 fatty acids.

Summary: Long term supplementation of fish oil may be beneficial for lactating women and preterm infants. It may reduce the symptoms of postpartum depression in nursing mothers.

What To Look For When Buying Fish Oil Supplements?

The label of the supplement should give full information on the content. It is best to check on the following:

  • Does the supplement contain the most important omega-3 which are EPA and DHA?
  • EPA and DHA amounts in each serving are important to note. A supplement may state 1000 mg of fish oil, however, the EPA and DHA content could be very low. The form of omega-3 will determine how much can be absorbed. Studies indicate that free fatty acids (FFA), triglycerides and reformed triglycerides (TG, RTG) and phospholipids (PLs) are better absorbed than ethyl esters (EE).
  • The GOED Standard: The Omega-3 Working Group at the Council for Responsible  Nutrition had developed the GOED Voluntary Monograph. It has set the standard for quality in the omega-3 industry since 2002. It ensures that omega-3 supplements are safe and of the best quality. The companies that took part in the creation of this monograph included the strictest regulations from across the world. Any fish oil that adhered to the Monograph standards can be sold in any part of the world. A third-party verification also ensures the quality of the supplement.
  • Freshness: Only supplements that are fresh can deliver benefits. A foul smell emanates if it goes bad. At this stage, the product can even be harmful to the body. The date of manufacture should be checked. The presence of the antioxidant vitamin E should be examined.
  • The Marine Stewardship Council inspects if a fishery is managed well and is viable. The MSC has the latest and comprehensive knowledge of internationally accepted fishery science and management. Consultations with scientists, conservation groups and the representatives of the fishing industries support the review and development of the MSC Fisheries Standard. Buying from MSC and the Environmental Defense Fund that certifies the supplement will make sure the product has secured good quality standards.

Frequently Asked Questions

What Are the Different Forms of Fish Oil?

Fish oil is from natural and processed foods. Processing can change the form of fatty acids. Some forms are better absorbed than others. In fresh fish, free fatty acids, phospholipids, and triglycerides are present.

Omega-3 fatty acids are available as triglycerides in fish oil. Ethyl esters from triglycerides are obtained from processed fish oil. It allows the adjustment of the concentrations of DHA and EPA. Reformed triglycerides are derived when the processed fish oils are reconverted into triglycerides. All forms have different health benefits.

How Many Types Of Omega 3s Are There?

There are 11 types of omega 3 of which EPA and DHA are the most important. Among many functions that these two long-chain fatty acids perform they also upgrade the interchange of nutrients in the cell membrane and control the body’s response to inflammation.

How To Get Adequate Amounts Of EPA and DHA?

EPA and DHA are entirely found in fresh fish and fish oil Plants like walnuts and chia seeds contain a short-chained omega-3 fatty acid known as ALA. Certain enzymes in the body can convert ALA into EPA and to DHA to a certain extent. However, the rate of conversion is extremely low that the scientific society considers it to no effect. The level of EPA and DHA present in an omega-3 supplement determines the strength of the product.

How Do You Know If You Are Getting A Sufficient Amount Of Omega-3?

Most Americans have deficient omega-3 levels. This includes users of fish oil supplements. The amount one needs is different and dependent on factors like health condition, diet, age, body weight and digestibility of the omega-3 supplement. A blood test will give a quick assessment of the individual need for this important nutrient. According to a survey, 95% of Americans have less than needed amounts of omega-3.

Do All Fish Oil Supplements Contain Optimum Amounts Of EPA/DHA Per Serving?

Some manufacturers of fish oil supplements claim that every dose serves 1000mg of fish oil. Fish oil naturally contains only 30% EPA and DHA which means that only 300mg is delivered in each serving. In this case to consume 2000mg of EPA/DHA a user needs 7 fish oil capsules.

Can Athletes Consume Fish Oil Supplements?

Fish oil provides benefits to the heart, muscles, and joints. There are no banned substances contained in the supplement and the individual gets what is listed as ingredients.

When Should I Take The Fish Oil Supplement?

The fish oil supplement can be taken at any time of the day. The recommendation is to have the dose with a meal as it can cause nausea on an empty stomach. A meal absorbs the nutrients of the fish oil supplement.

How Much Fish Oil Should I Take?

One should take at least 3 servings of oily fish during the week in addition to supplementation of 500mg of EPA and DHA. For those who do not consume fish, 900 mg of EPA and DHA are advised for daily intake.

Dosage of Fish Oil As Recommended By Scientists

Scientific research has suggested dosage for the following medical conditions:

To treat Hypertriglyceridemia (high levels of TG in the blood) daily intake of 1 to 15 grams of fish oil for 6 months has been used for this medical condition. Most experts recommend 3.5 grams of omega-3 fatty acids per day.

4to 15 grams of fish oil taken in a single or divided dose per day has been used to treat high blood pressure. This was for a period of 36 weeks. A four-week dosage of 3 to 15 grams of omega-3 fatty acids also has been administered for high BP.

To treat scaly and itch skin infection (psoriasis) 3.6 grams of EPA and 2.4 grams of DHA in the form of capsules have been used for a period of 15 weeks. The recommendation was for a daily intake of the dosage. An application of fish oil under the dressing up to 6 hours daily for 4 weeks also has been used.

Side Effects of Fish Oil

Up to 3 grams of fish is considered safe (GRAS) as stated by the Food and Drug Administration of the USA. Intake of dosage higher than 3 grams a day may lead to increased bleeding as blood clotting may get affected. 

Side effects are not adverse and may include, belching, loose stools, rash, bad breath. Immunity may get affected by high doses of fish oil. The user should first consult a doctor before consuming a high dose of this supplement. Farm-raised fish may be contaminated due to industrial effluents and chemicals in the environment. Fish oil supplements do not contain contaminants. 

The Final Note

Fish oil reduces triglycerides in the blood. It has notable benefits on the conditions of inflammation. However, its effect on cardiovascular events should be further researched. People with major depression seem to benefit from the presence of EPA which is the most effective omega-3 fatty acid.

Fish oil supplementation has proved to be a successful treatment for women who suffered recurrent miscarriages. Studies on the effects of fish oil on ADHD affected children have showcased an appreciable change in behavior outcome. Many investigations on the advantages of fish oil have been studied in the last 40 years and several trials have shown that it can be used to treat several medical conditions.

Fish is the most abundant source of the essential fatty acids of EPA and DHA. Since the required amounts cannot be taken through a food diet alone, a suitable supplementary diet recommended by a doctor will be helpful in meeting this nutrient requirement in the body.