Omega 3 fatty acids, anti-inflammatory fats found primarily in fish and fish oil, are the most commonly prescribed supplement in the world. And for good reason.
While research results are mixed in some cases due to an individual’s genetic mutations, diet, medications and lifestyle and how those factors affect omega-3 benefits, research has shown omega-3s in fish oil may improve triglycerides, inflammation, and brain and heart health.
Part 1 ranks and reviews this year’s top 10 fish oil supplements in order. Part 2 dives into the science of how they work and what they do for your body.
Starting with our #1 recommended fish oil supplement:
1. HealthWise Omega Fish Oil
For those who’re serious about ending crippling joint pain, HealthWise Omega is the best you can get.
No other fish oil can compete with the patented complex of 800 EPA and 600 DHA.
What does this mean for a fish oil supplement?
EPA and DHA are the crucial macronutrients inside fish oil that help the heart, joint, brain, organ tissue, and immune system.
From alleviating joint pain to providing your body more energy and focus, Healthwise Omega is one of the better daily habits you can have in the supplement space.
No “additives”. All natural, and made in the USA in an FDA-approved facility.
The all-around fish oil winner of 2018.
2. Nutrigold Triple Strength Fish Oil
The fish oil supplement offered by Nutrigold is one of the top-selling online brands.
Although not as powerful as our winner, its popularity is backed up by its quality.
Each softgel contains 1250 mg of fish oil; 1060 mg of this (88%) is omega 3 fatty acids. Of these, EPA and DHA account for 750 and 250 mg each.
Nutrigold derives its fish oil only from wild-caught whitefish from American waters, which sets it apart from some of its competitors. Though the capsule does include soy products, the soy protein has been removed, so if soy protein is a no-go in your diet, you should be okay.
If you have a severe soy allergy that can’t be pinned to the protein, you may still want to avoid Nutrigold Triple Strength.
For everyone else, though, it’s a tremendous deal: some of the most concentrated omega 3 fatty acids on the market for a pretty good price. Decent minimalist option.
3. Viva Labs Ultra Strength Fish Oil
If you want a fish oil supplement that really packs a punch, look no further than Via Labs Ultra Strength. Each capsule provides a full 1000 mg of omega 3 fatty acids, and 705 mg and 245 mg of EPA and DHA, respectively. Fully 83% of the fish oil was DHA and EPA.
This very high omega 3 content does make it a bit pricier than other products, but it’s hard to match when it come to raw omega 3 content.
Unlike other products on the market, there are no add-in ingredients: Viva Labs Ultra Strength provides no vitamin D3, no other omega fatty acids, and no flavoring. If you’re okay with a bit of a fishy smell when you open the bottle, it’s a good trade-off. This offering is for the minimalist; it does one thing (deliver a lot of omega 3) and it does it very well.
Note that you might also encounter Viva Labs’ products under the moniker of “Viva Naturals”; the company recently rebranded, so if you see a similar offering with this name, don’t worry—it’s not a copycat or imitation.
4. The Vitamin Shoppe Omega-3 Fish Oil
Would it surprise you if you found out that a fish oil supplement made by a brick-and-mortar supplement shop with wide name recognition was both inexpensive and effective? Well, it’s true!
The Vitamin Shoppe’s fish oil offering provides over 1000 mg of omega 3 per softgel, and of this, 680 mg are EPA and 260 mg are DHA. These combine to make up 76% of the fish oil in the supplement, much higher than many of its competitors.
Its mercury levels are also tremendously low, as are its levels of PCB toxins.
The one drawback of The Vitamin Shoppe’s fish oil offering is its labeling. Though the omega 3, DHA, and EPA contents are high, the listed amounts on the label don’t quite correspond to what you get in the supplement.
In this case, you actually get a little more than you’re paying for, but inaccuracies like this might be a sign that the quality control is not quite what it should be.
As for other ingredients, there are essentially none! Aside from the fish oil, the only things The Vitamin Shoppe Omega 3 Fish Oil supplement contains are gelatin, glycerin, water, and a bit of vitamin E to act as a preservative.
When it comes to value and quality, it’s very hard to beat this product.
5. OmegaVia Fish Oil
The fish oil supplement by OmegaVia is best viewed as a premium product. Even its branding gives it an air of precision and pharmaceutical care. Each softgel provides 1105 mg of omega 3 fatty acids, and of these, almost all of it is EPA and DHA (780 mg and 260 mg, respectively). Of the fish oil in the supplement, EPA and DHA account for 86% of the total.
As you’d expect, the mercury and PCB levels are extremely low; mercury was only at one part per billion, and PCB was below detectable limits as determined by an independent lab.
The label takes pains to point out that the fish oil is derived from wild-caught sustainably sourced Pollock and Whiting fish from Alaskan waters. The ingredients are similarly simple and high-quality; the only non-fish oil ingredients are the softgel constituents and a little bit of vitamin E to act as a preservative.
Though the quality is top-notch, there are other supplements that offer a better deal on omega-3s from a cost perspective. Nevertheless, OmegaVia fish oil is a good choice if you are looking for a top-quality supplement.
6. Dr. Tobias Optimum Omega 3 Fish Oil
As the top-selling fish oil supplement on Amazon.com, Dr. Tobias Optimum Omega 3 has big-time name recognition. Each softgel capsule provides 1000 mg of fish oil, including 400 mg of EPA and 300 mg of DHA.
The fish oil contained in the capsules is derived from sardines, and the softgel is made of gelatin, glycerin, and food glaze. Vitamin E and a preservative coating round out the relevant ingredients.
According to analytical testing in an independent lab, Dr. Tobias Optimum Omega 3 contains 2 parts per billion of mercury—the upper limit for safety is 100 parts per billion, for reference. Of the 1000 mg of fish oil per capsule, 845 mg of that was omega-3 fat, or 85%.
In all, Dr. Tobias Optimum Omega 3 is just what you’d expect from a top-seller: reliable, consistent, safe, and containing nothing outrageously fancy or expensive. It’s a good option if you want a simple, no-nonsense fish oil supplement, and its quality is good.
7. Nordic Naturals Ultimate Omega D3
Nordic Naturals has put a lot of effort into name recognition: they take care to point out that their fish oil comes from deep sea fish (anchovies and sardines), and that each batch is tested for toxin contents. Indeed, the mercury concentration and PCB (an organic pollutant that can accumulate in fish) is quite low.
The real interesting comparison is between Nordic Naturals’ own two offerings. In addition to the “Ultimate Omega D3,” the company also offers a lower-priced product called simply “Nordic Naturals Omega-3 Purified Fish Oil.” The ingredients are largely the same, but the concentration of omega 3 fatty acids is quite different.
The Ultimate version is definitely the one you want. It contains 685 mg of omega 3 per capsule, and 58% of the total fish oil in the product is DHA and EPA.
The regular version, in contrast, contains only 325 mg of omega 3 per capsule (less than half the Ultimate version!) and the EPA and DHA content makes up only 28% of the total fish oil content. Again, the DHA and EPA contents, in absolute amounts, are less than half that of the Ultimate version.
Given that the price difference is not a factor of two, it’s an easy call to make—get the Ultimate version.
8. WHC UnoCardio 1000+
The omega 3 fish oil offering from WHC supplies a hefty amount of EPA and DHA—670 and 395 mg per capsule, respectively. These fish oils are derived from a mixture of sardine, herring, mackerel, and anchovy.
It also contains vitamin D to boost your immune system and overall well-being; most people in cold climates don’t get enough vitamin D during the winter time seeing as the only natural way our body can produce it is via exposure to direct sunlight.
WHC UnoCardio is also naturally flavored with rosemary leaf. This helps mask the fishy smell that causes many people resentment when they take fish oil supplements.
Given that its imported from Belgium, its cost per serving is higher than average, but it’s quite pure, with less than 4 parts per billion of mercury and very close to the label-claimed amount of EPA and DHA, as determined by independent lab testing.
Another interesting quirk about WHC UnoCardio is that its softgel capsule is made from fish gelatin only, making it a good choice for pescatarians.
9. Nature’s Bounty Fish Oil
The fish oil supplement made by Nature’s Bounty is probably a familiar sight. It’s at drug stores and big box retailers across the country. How does its quality stack up?
In terms of raw omega 3 content, it is good but not great. Each softgel provides 750 mg of omega 3 fatty acids; of these, 435 mg are EPA and 240 mg are DHA. These fatty acids account for about 60% of the total fish oil content. This can be somewhat justified, based on its fairly low cost.
The quality is, again, good but not great. While it’s still at a safe level, the mercury content (five parts per billion) is higher than many of its competitors. Its PCBs are below detectable levels, though.
From an ingredients perspective, it contains some less desirable ingredients. While some of the highest-rated fish oil supplements have only a handful of ingredients—basically the fish oil plus a capsule—Nature’s Bounty contains a number of extra stabilizers, coatings, and preservatives.
This is less attractive if your philosophy is to limit your intake of these sorts of things, but if you care more about the big picture, it shouldn’t be a deal breaker.
10. New Chapter Wholemega Fish Oil
The fish oil offering from New Chapter is a big-time seller online, even if you don’t recognize the brand name. Each capsule contains a lot of fish oil—2000 mg—but the amount of omega 3 fatty acids is mediocre. Some 20% of the fish oil in the supplement comes from EPA and DHA.
Because of this, it ranks very low in terms of cost. Its dollar to omega 3 fatty acid ratio is one of the worst on the market; this is simply a function of the supplement being priced higher than average but delivering lower omega 3s per serving than average.
Like some of its competitors, New Chapter Wholemega supplies vitamin D to shore up your dietary intake, especially in the winter months. It also provides a battery of omega 5, 6, 7, 8, and 9 fatty acids.
If you’re looking to balance out your fatty acid ratios in your diet, it might be a good choice. These other fatty acids, however, are more prevalent in foods you’d typically find in your diet.
Omega 3s, and DHA and EPA in particular, are fairly rare, occurring in only a few foods. Incidentally, they are also the most-studied among the omega fatty acids when it comes to their health benefits.
11. Nature Made Cod Liver Oil
As a widely-distributed and best-selling brand, Nature Made is a common sight at your local drug store, and as you’d expect, they have a fish oil offering. This particular product derives its omega 3 fatty acids from cod liver, which is a readily available and inexpensive source for fish oil.
However, the quality of the fish oil in Nature Made Cod Liver Oil is low. Only 20 percent of the fish oil in it is actually EPA and DHA, the two essential omega three oils, and each of these only amount to 50 mg per capsule. Other products have about ten times that much EPA and DHA.
Worse, the mercury content is higher than average. Though still low enough to be at a harmless six parts per billion, it is nevertheless two to three times higher than the mercury concentration of many of its competitors.
Part of this may be because of where the oil is derived from. Fish contain some mercury to begin with, but within a fish, the liver has more mercury than the rest of the body, since the liver’s job is to remove toxins, like mercury, from the body.
For these reasons, Nature Made Cod Liver Oil finds itself at the bottom of these rankings.
Part 2: Who should take a fish oil supplement, and what can it do for you?
In the world of supplements, fish oil is one of the most widely known; as its name suggests, it is the concentrated and purified form of the fats that are found in oily fish like salmon, mackerel, and herring.
Its health benefits are widely known; some research suggests it may improve triglycerides, pregnancy and heart health, and possibly also decrease your likelihood of neurodegenerative diseases like Alzheimer’s disease or cognitive decline.
There are three main types of omega-3’s: ALA, DHA and EPA. ALA is alpha-linoleic acid, found mostly in plants like flaxseed and walnuts. The forms found in fish, seafood and eggs are eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). The body can convert ALA to EPA and DHA but it is a slow and inefficient process and there are various factors that can affect that conversion. Most of the research below focuses on the benefits obtained from supplementation with fish oil, which contains both DHA and EPA.
Benefits of fish oil
Fish oil, and its main constituent, omega-3 fatty acids, first entered the public eye after health researchers and nutritionists noted the powerful health benefits of a Mediterranean diet.
For example, a 1998 scientific study by Michel de Lorgeril, Patricia Salen, and Jean-Louis Martin in France compared the long-term health of people with coronary heart disease based on their typical diet (1).
After controlling for possible confounding factors, like smoking and age, the researchers found that the patients eating a Mediterranean type diet—one rich in fruits, vegetables, whole grains, olive oil, and fish—were associated with a substantially lower risk of cancer and an increased survival rate from cardiovascular disease.
Remember, these subjects were people who already had heart problems.
One of the main constituents of the Mediterranean dietary pattern is “healthy” fat, as contained in olive oil and especially in fish. The fats contained in fish are rich in omega-3 fatty acids, a particular type of polyunsaturated fat that is thought to have special benefits.
In the lab, under a microscope and in a Petri dish, omega 3 fatty acids demonstrate potent health-promoting effects. For example, a 1996 study by researchers at the University of Michigan demonstrated that omega 3 fatty acids have an anti-cancer effect on prostate cancer cells (2). This 20-year old study has faced opposition from more recent research that observed a link between higher blood levels of omega-3’s and prostate cancer risk (3, 4). More research is warranted to show causation as these findings may have been related to other factors.
When in vitro studies are performed (studies done within glass or in a laboratory) and results are found, naturally scientists and doctors wanted to see if they can replicate these effects in real living human beings instead of just in microscopic cells in the lab, also known as in vivo studies.
Clinical trials were undertaken; these ranged from small, poorly controlled trials to large multi-center interventions.
The best way to gauge the success of a major health intervention like this is not to look at just one study (even if it’s a big one)—it’s to look at meta-analyses, a type of study which pools the results from many different studies and tries to detect an underlying trend.
A 2006 meta-analysis published in the American Journal of Clinical Nutrition by researchers at a number of Boston-based medical centers looked at the results of 46 studies on omega 3 fatty acids (5).
After pooling the results, the authors concluded that increased consumption of omega 3 fatty acids, whether from actual fish or from a fish oil supplement, reduces the risk of overall death, heart attacks and other “sudden death” occurrences, and may also exert a protective effect against stroke (the evidence was not definitive on this point).
However, a 2018 meta-analysis of 10 studies found the opposite results as the 2006 meta-analysis – that omega-3 supplementation for 4.4 years did not significantly reduce the incidence of fatal or non-fatal heart disease or major vascular events (6). Why the conflicting results? This is still being studied but theories include that people may have increased fish intake, improved other lifestyle habits and/or increased statin use which have improved cholesterol values and heart health to such a point that the addition of omega-3’s offers no extra benefit.
Two of the main mechanisms of action for when health improvements are observed appears to be the ability of omega 3 fatty acids to reduce blood triglycerides and inflammation, both known risk factors for heart and other diseases. Though it seems counter-intuitive—how can consuming more fat reduce fat levels in your blood?—this hypothesis is backed up by good evidence.
A systematic review of fish oil supplements published by Guy D. Eslick and other researchers at the University of Western Sydney in Australia concluded that fish oil supplements produce a statistically significant decrease in blood triglycerides, with no apparent effect on cholesterol (7).
A separate study in 2010 in the American Journal of Clinical Nutrition found a 27% reduction in triglycerides when participants consumed 3.4 grams of omega-3’s via fish oil capsules per day. No other changes in cholesterol, inflammation or endothelial function were noted (8).
Vegetarian & Vegan Diets
Research has shown vegetarians to have lower blood levels of both DHA and EPA, since the diet primarily lacks food sources containing these fatty acids. Vegetarian diets are higher in ALA, an omega-3 precursor, but this is inefficiently and poorly converted to DHA and EPA in those with genetic mutations, chronic disease, and in the elderly. Also, some research has shown men to be poorer converters of ALA to DHA and EPA (9). Vegetarians in these categories may require algae-based omega-3 supplements to maintain optimal health.
Cognition and Brain Health
Benefits may extend beyond triglycerides. A 2010 study found that a 900mg daily dose of DHA over a span of 6 months enhanced memory and learning in those with age-related cognitive decline (10).
Additionally, emerging evidence indicates that fish oil may help prevent dementia and Alzheimer’s disease too—a review by the Cochrane Collaboration published in 2009 found that, while there are no high-quality clinical trials on fish oil and cognitive decline, circumstantial evidence from observational and epidemiological studies indicates that fish oil and omega 3 fatty acids in particular might have a beneficial effect when it comes to preserving cognitive function (11).
And even more convincing, a 2017 study found that those with the APOE4 gene, the strongest genetic risk factor for developing Alzheimer’s disease, showed higher uptake of DHA, when it was available, in select brain regions associated with cognitive decline in Alzheimer’s. In addition, lower serum DHA levels were associated with more brain plaque formation, known to advance cognitive decline (12).
Pregnancy and Breastfeeding
DHA plays a therapeutic role in pregnancy outcomes such as birth weight, pregnancy duration and neurocognitive function of the infant (13, 14). In addition, research shows DHA’s anti-inflammatory properties can have a protective effect for infants born pre-term through maternal supplementation while breastfeeding (DHA transfers through breastmilk to the baby) or through DHA-supplemented formula. Research has found an association between levels of DHA and EPA in breastmilk and improved hand-eye coordination in infants (15). Common doses used in these studies range from 400mg to 2000mg per day, higher than what is available in most prenatal multi-vitamins.
Recent research in the field of nutrigenomics shows how genetic mutations affect benefits obtained from supplements like fish oil (16). A 2017 study found that infants with a genetic mutation or polymorphism on the FADS gene family, fatty acid desaturates which control DHA and EPA metabolism, had only slightly increased DHA levels when supplemented compared to those without the polymorphisms (17).
Side effects of fish oil
Fortunately, for such a powerful supplement, the side effects of fish oil are minor in most. The exception is for those on blood thinners since omega-3’s as well as blood thinners reduce the ability of the body to clot which may lead to excessive bleeding during surgery or injury. Immune-suppression is also a concern in those who are already immune-compromised however these effects have been identified in doses under 5000mg per day.
According to a study by Chenchen Wang and other researchers, the most common side effect is mild gastrointestinal symptoms: burping, bloating, gas, etc (18). Enterically-coated fish oil supplements may reduce the incidence of upper GI symptoms like burping since the product is designed to resist digestion until it reaches the small intestine.
These typically only occur at high doses (over three grams per day of EPA and DHA). Fortunately, this is lower than the typical dosage. In fact, half of the three hundred-plus studies reviewed in that Wang et al.’s article reported no adverse effects at all.
Fish oil supplements may be contaminated with toxins due to the accumulation of these substances within fish tissue. Mercury, dioxins, and polychlorinated biphenyls (PCBs) are the most common contaminants which have been shown to damage the nervous system and are carcinogenic. Fish oils may also become oxidized which can lead to worsening of cholesterol levels. A Canadian study found that half of the fish oil supplements exceeded oxidization limits. To minimize the potential of oxidation, keep your fish oil supplements away from heat and light. Smell your fish oil as this is one way to identify oxidation and discard supplements that smell rancid. Since not all oxidized products may have a malodor, purchase supplements that come from reputable sources and have been third-party tested for contamination and oxidation.
Two brands that have been third-party tested by Consumer Labs and found to contain too much or too little omega fatty acids than what is listed on the label is Kirkland’s Signature Wild Alaskan Fish Oil and VitaCost KriaXanthin Antarctic Krill Oil.
When should I take fish oil?
The best time to take fish oil is during meals. Why? Easier to digest. Another reason why fish oils are best taken with food is because the fat consumed in your meal will stimulate the pancreatic lipase enzymes, which cause dietary fat to be broken down in the digestive system. The more of these enzymes that are present when you take a fish oil supplement, the more omega-3 fatty acids will be broken down and absorbed by your large intestine.
Most studies on the clinical and health benefits of fish oil use between one and three grams of fish oil per day. The American Heart Association recommends people with previous heart attack or heart failure consume one gram (1000 mg) of omega 3 fatty acids per day (7). For people who need to lower their blood triglycerides, larger doses of two to four grams (2000 to 4000 mg) per day may be needed. Pregnancy and lactation needs are typically above 400mg per day.
No recommendation is given for healthy people; they are simply encouraged to eat a diet rich in fish and seafood and plant sources like flaxseed oil, canola oil, and walnuts. Regardless, if you are looking for a number to use as a guideline if you are healthy, one gram or 1000 mg per day is probably a good place to start.
While research is still ongoing and diet is always the preferred route of intake, omega-3’s in fish oil is a relatively low risk way to improve many markers of your health.
You may not need to take a fish oil supplement if you are healthy and you already eat oily fish at least two times a week. If not, start with one gram of omega 3 fatty acids per day. Make sure you check the label on your supplement; sometimes the omega 3 fatty acid content is far lower than the fish oil content and weight.
For BodyNutrition‘s #1 fish oil recommendation, click here.