Consumer’s Guide to Buying the Best Fish Oil

white plastic bottle on side with best fish oil soft gels spilling out


If you’re looking for the best fish oil there are a number of important factors to consider before buying them.

Fish oils are a natural source of the omega 3 fatty acids, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA).

EPA and DHA offer many health benefits, including lowering elevated triglyceride levels and enhancing mood and mental health.

You may think that all products are the same, but there can be a big difference in the actual ingredients, quality and purity of the fish oils.

Here you’ll learn how to buy the best fish oil for maximum health benefits and value for your shopping dollars.



Five Ways to Get the Best Fish Oil


  1. Choose the best fish for the best fish oil
  2. How do you like your oils – distilled or refined?
  3. Is there a Certificate of Analysis?
  4. How much EPA and DHA per dosage?
  5. Liquid oils or soft gel capsules?

Rule Number 1 – Salmon, Mackerel, Sardines and Anchovies make the Best Fish Oils


pile of mackerel and sardines for the best fish oilsMarine biologists claim that fish that live and breed in colder waters tend to have higher amounts of the omega 3 fatty acids, EPA and DHA, compared to their counterparts that live in warmer waters.

They believe this is due to a biologically need to retain more body fat to keep their cell membranes more flexible and pliable in the colder ocean waters.

Salmon, herring, mackerel, sardines andanchovies naturally contain higher amounts of these healthy fats, compared to Sole and Yellow fin tuna.


Rule Number 2 – Choose Between Distilled or Refined Fish Oils


There are mainly two ways how fish oils are made: Molecular Distillation and a Refinement process:

1. Molecular Distillation uses a vacuum and high temperatures to produce an ethyl ester of the omega 3 fatty acids.

The EPA and DHA in fish oils are naturally made up of triglyceride fatty acids. In molecular-distillation, the triglyceride fatty acid chains are replaced with an ethanol chain. This converts the fatty acids into an ‘Ethyl Ester’ which are called omega 3 concentrates. Molecular distillation is reported to produce a highly-purified oil that may be more pure than oils produced by other methods.

There’s conflicting reports on how efficiently our bodies can absorb these ethyl ester fatty acids. Some studies have shown there’s no difference between the absorption rate of triglycerides and ethyl fatty acids. Other studies claim triglycerides are better than ethyl esters for absorption.


diagram of lab beakers and test tubes


2. Refining Oils is another method used to make fish oil. This process uses soap bases, bleaches and deodorization to remove contaminants, unwanted odors, colors and flavors. This was the most popular way to make fish oil before molecular distillation was invented.

Refined oils are generally more affordable than molecular-distilled products due to lower production costs. However, some scientists claim it produces a lower concentration of EPA and DHA, compared to molecular-distillation.

While the refinement method meets the minimum purification levels recommended for these types of products, it can’t match the ultra-purification levels attained through molecular distillation.


Rule Number 3 – Check for Certificates of Analysis


chemist testing best fish oils for purityThe best fish oil is one that has the highest purity level with minimal contaminants.

In most countries, the fish oil industry isn’t completely regulated by Government or Health Agencies. Therefore, you need some method of reliable testing to ensure the product meets certain criteria for freshness and purity.

At this point, a Certification of Analysis is the only way you can be sure that the fish oils meet minimum standards set forth by international organizations, such as the GOED (Global Organization for EPA and DHA), Council for Responsible Nutrition (CNR) and International Fish Oils Standards (IFOS).

Fish oil manufacturers based in other countries may follow their own nationally set standards, such as the European Pharmacopoeia.

Example of standards set forth by the International Fish Oil Standard:

  • Mercury – less than 100 ppb (parts per billion)

  • Arsenic – less than 100 ppb

  • PCB’s – less than 90 ppb

  • Lead – less than 100 ppb

  • Dioxins and Furans – less than 2 parts per trillion

  • Omega 3 fatty acids – at least 60% concentration


Rule Number 4 – Check How Much EPA and DHA per Dosage?


calculator for best fish oil dosages


The main reason most people will take fish oil is for the omega 3 fatty acids, EPA and DHA.

Generally, the higher the dosage of omega 3 fatty acids, the more health benefits may be derived from it.

The majority of fish oil soft gels come as a 1000 mg. sized soft gel. However, this doesn’t mean that you’re actually getting 1000 mg of EPA and DHA in each soft gel.

Here’s how you calculate how much EPA and DHA you’re getting per dosage:

  • Divide the amount of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) into the total amount per soft gel.

    For example, a 1000 mg. soft gel containing 300 mg. of EPA and 200 mg. of DHA would provide an omega 3 concentration of 30% EPA and 20% DHA.

  • Our research has found that the majority of standard fish oil gels provide a 30% concentration of EPA and DHA.

  • The ingredient label will usually provide the EPA and DHA dosage per soft gel. You should look closely at the bottle label to determine how many soft gels are used to provide the actual listed ingredients. Some products may use 2 – 4 soft gels per dose to provide the promised dosage of EPA and DHA listed on the label.


Rule Number 5 – Choose between Liquid Oils or Soft Gel Capsules


You can get fish oils in bottled liquid oils and soft gel capsules.

There are advantages and disadvantages to each type:

Liquid Oils:

  • Will usually provide a higher concentration of EPA and DHA per dose.

  • May cost more per bottle than soft gels, but this higher cost will be offset by a lower cost per gram of EPA and DHA.

  • Liquid fish oils should always be packaged in dark bottles to prevent light exposure and stored in a cool place to heat oxidation of the fatty acids.


Soft Gels:

  • Capsules and soft gels may be a more convenient way to package and protect fish oils.

  • The soft gels can help prevent the oils from going rancid and also prevent tampering with the product.

  • People with digestion issues may benefit from using a enteric-coated fish oils; these products help improve absorption and reduce fish oil side effects due to poor gastrointestinal absorption.

  • Soft gel capsules can be made of animal or plant-based gelatin. The capsules could also be coated with other man-made or natural ingredients.


Review for Buying the Best Fish Oil Supplements:

  • How Much EPA and DHA are You Getting? As an example, a 1000 mg. capsule containing 300 mg. of EPA is a 30% concentration and a 1500 mg. tablespoon of liquid fish oil containing 750 mg. of EPA is a 50% concentration.

  • Calculate your Cost per Dose: Most liquid oils provide higher amounts of omega 3 fatty acids per dose. However, you can find high concentration soft gels that match or surpass many liquid supplements.

  • Is there a Certificate of Analysis? The best fish oils have a Certificate of Analysis or test results from a third party lab. This helps you determine if there are any detectable levels of mercury, PCB’s, dioxins and other contaminants.


List of The Best Fish Oil Brands

While you can find many high quality products that qualify as ‘the best fish oil’, there are a few products that stand out above the rest.

Many of the following products meet the above 5 criteria for a good fish oil – they all provide high concentrations of EPA and DHA in a highly-purified state with 3rd-party testing or certification.

Many of these products are also made by companies that specialize in producing fish oils and omega 3 concentrate products.


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Author Details
Kevin is a full-time blogger with a passion for functional, whole food nutrition. A former Registered Respiratory Therapist with over 25 years experience in Intensive Care and Emergency Medicine, he also has additional training as a Certified Natural Products Advisor. He enjoys a vibrant lifestyle that includes healthy foods, workouts focusing on core strength with flexibility and longboarding to stay fit and agile.