What is High Quality Fish Oil?

Posted on 02 Jan 2009 04:19

by Eric Troy

Fish oil paranoia is rampant right now.

Of course you do need to be careful what fish oil products you use. There is always some contaminated product floating around out there. Even some of the nutritional experts seem to be a little misled, however. Perhaps because they have more money than I it’s easy to get lazy and assume more expensive means better quality.

See also: 17 Common Fish Oil Questions Answered.

I understand if you have first hand knowledge of a certain product. But I’m seeing people implying that a common retail brand is inferior simply based on cost. Or that a concentrated product is automatically higher quality than a less concentrated one. Concentration is not a guarantee of quality.

But even a very involved search will reveal that most all of the information about the manufacture of fish oil products is provided by the manufacturers themselves.

Before I go any further I’ll give you one simple guideline. To help you choose a product, rely on independent “third-party” organizations. Do not rely on supplement vendors or the manufacturers although some of them are quite honest. And do not rely on a nutrition expert unless they are both unbiased and the owner of a testing laboratory. No matter how expert they are, their opinions are just that, opinion. And many nutrition experts have more than a casual relationship with one or more supplement companies. Sorry if that pisses anyone off, friends or otherwise.

various fish oil supplement containers

Obviously most cannot afford to submit their product to an expensive laboratory. I’d suggest a subscription to consumerlab.com, a supplement watchdog which regularly tests and provides updates on a large number of products (I am not affiliated in any way with consumerlab…except that I pay for my own subscription).

Consumerlab.com is an extremely useful resource on supplements. I recommend you buy a subscription and read the fish oil report There is a great deal of useful information to be found in this report as well as many other reports.

Is a more expensive fish oil better?

Maybe. Maybe not. It could be that a more expensive product is better. Certainly some of the best oil suppliers around tend to be more expensive. It costs more to provide a more concentrated product, for instance. To ensure that the product is pure. And to ensure that it is processed quickly and efficiently. Companies like Carlson and Spectrum are top level manufacturers and their products are certainly more expensive than something you might get at your local drugstore. However, there are many products on the market that are even more expensive than these and frankly are nothing more than snake-oil.

What is quality fish oil?

The answer is complicated (but it doesn't have to be). You’ve probably read the simple answer many times. Fish oil needs to be molecularly distilled. This distillation process is a relatively non-damaging way to remove contaminants and to concentrate the product.

But what fish oil really “needs” is to be is as free as possible of contaminants such as lead, mercury, cadmium, dioxins, PCBs, and pesticides. This can be accomplished through the refining process, or can be assured through the use of fish that are low on the food chain and/or come from less polluted waters and then confirmed thought independent third party testing. I would trust a manufacturer that provides third party testing results whether their product is molecularly distilled or not over one that does not provide such reports. If these fish also come from a non-endangered, sustainable population that is certainly a plus.

It needs to contain a decent amount of the key omega 3’s, EPA and DHA. A decent amount is open to opinion, but I would expect at least 30 percent and up to 80 percent EPA/DHA.

Fish oil needs to be non-spoiled.

Contamination of fish oil products seems to be common knowledge now. But the problem of rancidification of fish oil and of oils in general is not as well known. A fish oil product is highly likely to be spoiled. If you use capsules I'd actually recommend puncturing one or more of the capsules and smelling the oil. If it smells extremely fishy it's probably rancid. That would mean that the manufacturer was not careful enough, didn't process the oil quick enough, etc. Fresh oil should not have any strong fishy smell any more than fresh fish would.

I have noticed that many of the more concentrated products have the strongest fish smell while also claiming to be the “purest”. By contrast a high quality bottle of Spectrum or Carlson fish oil, for example, will have very little fishy smell when first opened.

Fish oil should be kept in the fridge after opening to be on the safe side and keep them their freshest. Bottled fish oils MUST be kept in the fridge.

For capsules, some makers just say store in a cool, dry, place. Or, between 60 to 70 degrees in a dry place. It probably shouldn't come as a surprise that manufactures do not agree on whether the product should be refrigerated. The trade off is moisture that collects on the caps when you open the container of cold capsules. There is most likely an absorbent in the bottle. Which is the best? I'd go for refrigeration until I find reliable info otherwise. As stated, for non-encapsulated bottled oils, there is no question: DEFINITELY refrigerate. I, personally, refrigerate my capsules as well.

If you use a bottled product buy one that you can finish within about two weeks. DO NOT buy fish oil capsules in bulk. This is a downright silly thing to do. I buy no more than 300 to 500 at a time depending on how many I need to take and that depends on concentration. There are some dubious practices going on with bulk fish oil capsules. One thousand fish oil capsules for the price of 200 is not a bargain. It's a waste of fish oil capsules. You won't be able to use them before they spoil, unless the whole family downs them daily. So the fewer capsules the better. The quicker you use them the less chance you are consuming rancid product. Fish oil is highly perishable and the process of rancidification begins as soon as the manufacturing process begins, though the process of oxidation.

I don’t get it, aren’t there ways to stop this? And isn’t it vacuum sealed?

Oxidation is a clear cut thing. Some few products may be spoiled in the bottle, whether caps or liquid. But the majority of them will pass muster in a simple lab test right after opened. But as I stated fish oil begins the process of rancidification through oxidation immediately. As soon as they start separating the oil it is going to start going bad. Why do they add vitamin E or other antioxidants? For this very reason. And it is pretty effective, based on the info at hand, but it can only prevent further oxidation not reverse it or stop the chain reaction that has already occurred.

Saturated oils last a long time. Monounsaturated (like olive oil) is second. And polyunsaturated (like fish oils) are very perishable. Cold is a way of slowing down the process of oxidation. There is nothing a manufacturer can do to take polyunsaturated oil and stop that from eventually happening. Not without making the oil worthless.

Some of the better ones are sealed with nitrogen rather than being vacuum sealed. That creates and inert environment which is even better. But it doesn't matter whether they are vacuum sealed or not. The word chain-reaction explains it. You see, even if you never open the bottle once the process of oxidation has begun it is automatic and does not require the presence of more oxygen. Like wise exposure to light causes photo-oxidation. The by-products initiate reactions that lead to other by-product, and so on until the oil is rancid. It's called auto-oxidation.

Every time you open the container it just speeds the process along. Especially exposure to light. From what I’ve read photo-oxidation is even more robust. This process produces peroxides, which may be toxic to the body. The presence of these end products of oxidation are what testing labs look for to evaluate the freshness of fish oils. Fish oil, though, is just darn hard to keep fresh.

Fish oil is not as easy to produce as seed oils. For that reason, ignoring all the possible contaminants, it is harder to keep fresh. Just think about what you'd have to go through to extract just oil from the body of a fish. A lot of steps involved in that!

With seeds you press them and the oil squeezes out. The other particulates in unrefined seed oil simply add to the nutritional value of the oil. In fact, the refining of seed oils has more to do with consumer expectation than necessity. Filtering and refining can help to raise the smoking point of oils for cooking. It can also help extend the shelf life. But it is not better for you. Consumers associate a clear product with quality. But in reality, the less refined most food oils are, the better.

But fish oil must through necessity be refined. You squeeze a fish, and a lot of gross stuff squeezes out. The highly delicate nature of the oil makes the refining process more expensive. So, while I maintain that you do not have to buy highly expensive products, expect to pay for quality. This is another reason not to buy very cheap, bulk products.

The products I am talking about are not those you might get from your drugstore or your warehouse club, however. Most of these do pretty well on tests. However, do not buy fish oil of unknown origin from an internet based bulk retailer unless they can provide detailed information as to manufacturing and an independent quality report. It may come as a surprise to many; one does not need any special qualifications to sell supplements to the public. No specialized knowledge in supplement manufacturing or nutrition is needed. A retailer dealing in bulk may provide knowingly inferior products or, on the other hand, may be simply clueless. They may have no more in-depth expertise about the products they sell than the manager at your grocery store.

All that being said and given that I believe in trying to get the best you can, I also think the benefits of fish and fish oil products probably outweigh the potential risks for otherwise healthy people. Fish oil products, for the time being are testing very well in general and may well be the safest way for your EPA/DHA.

Pharmaceutical Grade Fish Oil

Public concerns over purity have, inevitably opened another avenue for the supplement companies. These companies are well aware that the average consumer lacks any real understanding of the issues, but simply harbors a vague fear of heavy metals or other contaminants. A perfect opportunity for clever marketing.

There are a few companies right now that are touting "pharmaceutical" grade fish oil, based on just that kind of reasoning. No Pharmaceutical grade monograph exists in the United States for fish oil supplements. There exist no standard definitions for this other than what those companies would try to make people believe. If your fish were a usp verified dietary supplement it might bear on its label a symbol like this one:


The USP verification service for dietary supplements has nothing to do with manufacturers of pharmaceutical grade ingredients. It is simply an inspection service that the USP provides to ensure that supplement companies meet certain stringent guidelines. Although this service includes the assurance that the product disintegrates and dissolves properly the USP makes NO claims of efficacy for the products. Only that they meet the manufacturing guidelines.

In addition to verification services for finished products the USP provides verification for the inactive and active ingredients used dietary supplements. The mark awarded for ingredients looks like this:


Much different than the mark awarded for USP verified pharmaceutical ingredients which actually includes the word pharmaceutical:


This has not stopped certain fish oil companies from trying to compare the USP dietary supplement verification with the word "pharmaceutical" and the term "pharmaceutical grade".

Pharmaceutical grade as a term is meaningless. There is nothing to stop any supplement manufacturers from claiming that their supplement is pharmaceutical grade. This is similar to the use of the words "pure" and "natural".

Indeed, many of these manufactures actually claim that the term means "99% Pure". There is absolutely no standard purity for pharmaceutical ingredients. They are made to different purities depending on their intended use. The USP verification service is meant to ensure that the amount of active ingredients meet the claims of the manufacture. That is all. A product does not have to be "99% Pure" to be USP verified. It simply needs to meet it's label claims. So of course there is an advantage in feeling sure that your product meets it's label claims but it is far from necessary for a product to have the USP stamp for one to feel assured in purchasing it.

Interestingly, if one searches the term pharmaceutical grade or "what is pharmaceutical grade" ninety nine percent of the results will be for fish oil products! Clearly the term is "100% Hogwash". Apparently, an actual monograph for Omega 3 Fatty Acids Product standards is in the works. Be aware that once this monograph is final, products meeting the standards will bear the USP stamp. No stamp no "pharmaceutical grade".

More recently, marketing has been based on the amounts of DHA to EPA. There has been some research into the relative importance of these two fatty acids. Some companies are touting products with much higher amounts of DHA. That they are willing to let you have for only around 3 times the cost of most oils.

I’m not even going to bother getting into the research because that is not the purpose of this article. I’ll easily put this to bed. As of now, these products have no real claim to being higher quality than any other product. Up until very recently, we were still not sure that fish oil was even an effective way to get EPA and DHA instead of fish. And many nutritionists were recommending getting your fish oil from fish as much as possible. Some still do. We’ve just now begun to feel confident about fish oil as a primary source of these omega 3’s. It is absolutely ludicrous to jump to the extreme of buying designer fish oil with bells and whistles. Gucchi fish oil is not necessary.

I mentioned Consumerlab. The environmental defense fund is also a good source of information on choosing fish oil brands.

Environmental Defense's survey

Environmental Defense contacted 75 companies whose fish oil products are commonly found in supermarkets, pharmacies and health food stores, and asked them (1) whether they purify their fish oil to reduce or remove environmental contaminants; (2) what methods they use to purify their fish oil; and (3) what standards they comply with regarding acceptable levels of contaminants.

Environmental Defense solicited information on mercury, PCBs and dioxins, since these three pollutants comprise the majority of consumption advisories for fish caught in the United States and could also be present in fish used for fish oil supplements. (Generally, fish oil comes from fish that are caught to feed animals, not humans.)

What standards does Environmental Defense consider sufficiently stringent?

//There are a variety of standards for allowable limits of contaminants in food (including dietary supplements). For this study, Environmental Defense evaluated standards from the following government agencies: the State of California (Proposition 65), the U.S. Environmental Protection Agency (EPA), the U.S. Food and Drug Administration (FDA), the Canadian Food Inspection Agency, and the European Union.

Surprisingly, allowable levels of contaminants vary greatly between agencies, with the FDA's standards being the least stringent. PCB standards vary the most. The FDA's tolerance level for PCBs is 2,000 parts per billion (ppb), while the State of California's limit under Proposition 65 (the most stringent standard) is only 90 ppb, assuming daily consumption of one 1,000 mg fish oil capsule. Similar disparities exist for mercury and dioxins. Since EPA's and California's Proposition 65 limits were the most protective of human health, we used these standards as the baseline for our survey.

In addition, the Council for Responsible Nutrition (listed at right) — a trade association comprising many of the companies surveyed (see chart for full results) — established voluntary standards equal to or more stringent than those set by EPA and California's Proposition 65.//

_ Survey results

Many of the companies contacted provided high-caliber responses, indicating that they take potential health risks from contaminated fish oil supplements seriously. Most companies said they used molecular distillation and steam deodorization technologies to remove environmental pollutants from their fish oil supplements. These highly effective purification processes use a combination of pressure and high temperature to separate pollutants from omega-3 fatty acids.

Overall, more than 80% (61) of the 75 companies contacted verified that they have met the strictest U.S. standards for contaminants. Twenty-one companies' responses were incomplete, and seven companies did not respond (note that 14 companies provided complete information for some products while incomplete for others). One company, Omega Protein, said it complied with the least stringent standards (FDA's) but did not respond to our follow-up inquiries about whether it also adhered to other stricter standards. (See chart for full results.)

In short, most fish oil supplements appear to be adequately purified and safe. Consumers who take fish oil supplements should consider purchasing them from companies that verified they have met the strictest U.S. standards for contaminants.

International Fish Oil Standards Program (IFOS Program)

Here is the background on the IFOS program provided to manufacturers. I've not included every little detail of the submission process but the info on the testing itself.

Last time I checked only three oils were listed. But posting is not necessary.

Nutrasource Diagnostics Inc., (“NDI”), a University of Guelph spin off company, is the world leader in omega-3 diagnostic care and international fish oil standards testing. NDI was formed in 2001 to commercialize omega-3 related assays developed by Lipid Analytical Laboratories in the University’s Research Park Center.

Program Summary
Since that time, NDI has launched a series of certification and validation programs in the nutraceutical and functional food field, with a particular emphasis on omega-3 related products. One of these leading programs is the International Fish Oil

Standards Program
(“IFOS”), which clinically validates omega-3 products for concentrations of key ingredients and levels of contamination. Consumers across the world may access the web-site IFOSPROGRAM.com to view batch reports confirming the results of third party validation testing.

Testing Information
NDI, through its certified and accredited reference laboratory partners, tests the product for PCB, Mercury and Oxidation levels in accordance with Council for Responsible Nutrition’s voluntary monograph on omega-3 products and safety standards for human consumption. Dioxin and Furan levels are tested against the World Health Organization’s standard and omega-3 concentration is tested and compared with the product label claim. PCB, Dioxin and Furan levels are tested using liquid chromatography mass spectrometry at a detection limit of parts per trillion. Mercury is tested using cold vapor atomic absorption spectroscopy at a detection limit of parts per billion. Omega-3 content is tested using gas chromatography advanced capillary techniques as a percentage of weight, and Oxidation testing is conducted using a titration method for peroxide and uv-visible spectrophotometer for p-anisidine under numbered official AOCS methods Cd 8-53 for peroxide and Cd 18-90 for p-anisidine respectively.

Although the standard detection limit expressed for each category is set by the governing organization, the IFOS program tests the products at far lower levels of detection in most categories, based on the most advanced analysis technology platforms available. As the sophistication of the instrumentation increases, the IFOS program will continue to update the testing regiment to ensure it is on the leading edge of science. © 2006 Nutrasource Diagnostics Inc. All rights reserved.

Consumer Benefit
With growing contamination concerns for the consumer, and recent clinical data suggesting the negative effects of mercury and PCB’s from edible marine sources, the IFOS program continues to grow in popularity and prove its value as a reliable source for third party validation. Consumers are becoming increasingly aware of the many clinically established health benefits of omega-3, but are equally concerned with contamination issues. The IFOS program delivers a suitable venue for the omega-3 supplement industry to showcase credible product sources.

IFOS Tests for Posting on the Web-site:

Dioxin and Furan Testing (results in PPT)
PCB Testing (results in PPT)
Essential Fatty Acid Testing (results in mg/g)
Oxidation (peroxide, anisidine, total oxidation – results in mq/kg)
Mercury Testing (results in 10 PPB)
Cadmium (results in PPM)
Lead (results in PPM)
Arsenic (results in PPM)
Nickel (results in PPM)

Additional Third Party QC Tests Available

Toxin Analysis
PDBE (results in PPT)
PAH (results in PPB)
OC Pesticides (results in PPB)
© 2006 Nutrasource Diagnostics Inc. All rights reserved

Nutritional Analysis

Basic Nutrition Facts Label (U.S. or Canada)
(Includes calories, total fat, saturated and trans fat, cholesterol,
sodium, carbohydrates, dietary fiber, sugars, protein, Vitamin A,
Vitamin C, calcium, iron)
Dietary Analysis for Nutritional Fat Content Only
Trans Fats
Vitamin A
Vitamin B1 (Thiamine)
Vitamin B2 (Riboflavin)
Vitamin B3 (Niacin)
Vitamin B6 (Pyridoxine)
Vitamin C
Vitamin D
Vitamin E
Cholesterol (results in mg/g)
Stability Testing
Accelerated Stability Testing per time interval
Peroxide Value (solid)
Acid Value
Trace Elements
Aluminum (results in PPM)
Antimony (results in PPM)
Barium (results in PPM)
Beryllium (results in PPM)
Bismuth (results in PPM)
Boron (results in PPM)
Calcium (results in PPM)
Chromium (results in PPM)
Cobalt (results in PPM)
Copper (results in PPM)
Iron (results in PPM)
Lithium (results in PPM)
Magnesium (results in PPM)
Manganese (results in PPM)
Molybdenum (results in PPM)
Potassium (results in PPM)
Rubidium (results in PPB)
Selenium (results in PPM)
Silver (results in PPM)
Sodium (results in PPM)
Strontium (results in PPM)
Tellurium (results in PPM)
Thallium (results in PPM)
Tin (results in PPM)
Uranium (results in PPM)
Vanadium (results in PPM)
Zinc (results in PPM)
Microbiological Analysis
E. Coli
Total Coliforms
Yeast and Mold

Client may request any combination of tests as required. Subscription to the IFOS web-site posting service is not mandatory. Clients may request tests for internal quality control only, without subsequent web-site posting. In such cases, client will receive a confidential certificate of analysis.

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