How To Select the Best Omega-3 Fish Oil

Fish oil is widely acclaimed for its health giving properties – the benefits of which span across the entire health spectrum. However, considering the vast range of fish oil suppliers and products currently available, you’ll understandably be hard-pressed to find the one that is not only the most effective, but also the purest, freshest and most natural fish oil in the world – well, at least until you’ve finished reading this article.

Every effect has a cause. One thing leads to another – it’s a fact. In terms of aging and deteriorating health conditions, your body’s main culprit is almost always inflammation. What makes inflammation so deadly is that it sneaks up on you and over time, the cumulative effect is a chain reaction of various health conditions ranging from arthritis and chronic pain to more serious issues such as atherosclerosis, aneurisms, strokes, brain disorders and ultimately, death.

Why is fish oil so important?

Most scientists and health professionals believe that it is the anti-inflammatory properties of fish oil that enable it to provide so many health benefits particularly in areas of the: Heart, Brain, Joints, Skin, Immune system, Vision and, Digestion.

However, like any nutritional product on the market today there are good and bad ones. Fish oil is no exception. With a bad one you may be unwittingly introducing substances into your body that you do not want, for example: mercury, PCBs or even increasing your load of free radicals.

You owe it to yourself to use only the purest, and thus the safest omega-3 fish oil available, plus it also has to be the most effective in order for you to receive the benefits above. If you and your family want the best product possible there are certain ‘rules’ that you need to follow.

They are:

  • ·    Anti-inflammatory properties: Does your current fish oil have the best possible anti-inflammatory properties?
  • ·    Bio-availability: It must be in its natural form.
  • ·    High content of quality omega-3 and DHA: Be reasonably high in omega-3 with the dominant essential fatty acid being DHA.
  • ·    Purity: The fish oil must be free from any contaminants with supporting evidence to prove it.
  • ·    Freshness: This means low oxidation levels; once again with cold, hard evidence to back-up such claims.

These ‘rules’ will be individually explained in more detail throughout this article.

Omega-3’s best catch of the day

Which fish species is the most effective when it comes to inhibiting inflammation?  Our research points to hoki.

In addition to its exceptionally high levels of purity and freshness (when correctly handled and processed), hoki fish also seem to contain a fascinating ‘x-factor’ which turbo-charges the efficacy of its oil – especially when combined as a natural triglyceride with a highly concentrated and molecularly distilled fish oil (more about this ‘x-factor’ and the various types of fish oils will be revealed later).

This fish is found off the coast of New Zealand in the Southern Ocean. The hoki fishery in New Zealand is controlled by the New Zealand government and is considered to be the best managed and sustainable fish resource in the world.

Unlike most fish which are caught by large factory ships and frozen at sea, hoki fish are caught by smaller vessels fishing within seven hours travelling from the hoki fishing grounds. The catch is able to be kept fresh in ice and processed immediately upon arrival back on shore.

Amazing anti-inflammatory alchemy

As mentioned earlier, inflammation is VERY important, it can have profound detrimental influences to your heart and cardio-vascular system, as well as being a precursor for many other ailments. This is why Xtend-Life researchers have focused so much on improving the anti-inflammatory properties of the Omega 3 / DHA Fish Oil with amazing success – a product that is now setting new standards for fish oil products.

This was established as part of a study carried out this year by Trinity Bioactives, part of the Wellington School of Medicine in New Zealand.  The study tested the inflammation inhibition properties of three fish oils while using aspirin as a dose-related control. The three fish oils were:

  • ·    A concentrated tuna oil with 85% omega-3
  • ·    A ‘normal’ consumer fish oil 18/12 which consists of 18% EPA and 12% DHA
  • ·    Xtend-Life’s Omega 3 / DHA Fish Oil

Inhibition Properties:

  • ·    Normal fish oil – 14%
  • ·    Concentrated tuna oil – 20.6%
  • ·    Xtend-Life’s Omega 3 / DHA Fish Oil – 38.1%


Your digestive system is probably the most efficient production line known to man, however it is as natural as nature itself. It converts food particles into natural molecules that the body recognises and therefore can easily absorb. The food particles are now said to be bio-available to the body.

Bio-availability is influenced by the molecular shape of fatty acids, sugars, proteins, and other nutrients that are easily absorbed by the body. When it comes to fish oil, the benefits associated with it can only start taking effect once the body has absorbed the nutrients contained within it. The more natural the molecular structure the better.

So, when assessing how ‘natural’ fish oil is, it is important to know about the different forms currently available on the market:

  • 1.    Natural fish oil comes in a triglyceride form. This is the oil that you get when you ‘squeeze’ the fish and extract the natural oil from it. The drawback from this particular form of fish oil is that it usually has low overall omega-3 content because it’s not concentrated and generally has high levels of contaminants such as heavy metals, PCBs, dioxins etc.
  • 2.    Ethyl ester oil occurs when you take natural triglyceride oil and concentrate it whilst molecularly distilling the oil to eliminate purities. The concentration process cannot take place until the natural triglycerides are converted to an ester form. The ester form is still in a semi-natural state because it is the result of a process that naturally occurs in the body to allow for bio-availability. It’s not uncommon to double or even triple the omega-3 content of a fish oil using this concentration process.
  • 3.    Synthetic triglyceride oil is another form of fish oil that is very common and marketed as ‘natural’ when in fact it isn’t. It is a triglyceride, but not a natural one. It is produced after concentration. As mentioned above, the natural triglycerides are converted to ethyl esters for concentration. This is perfectly fine however; but some manufacturers then re-convert the esters back into triglycerides – a synthetic form which occurs as a result of this re-conversion process. The original position of the triglyceride’s carbon bonds change and the molecule’s overall structure is altered. Part of it becomes foreign to what the body is used to - negatively impacting the bio-availability of the fish oil. Why do they do it? Because they can state that it is a triglyceride form and infer to the customer that it is natural – which in actual fact, it’s not.

It’s about quality and synergy

There are some fish oil products out there that are saturated with high levels of omega-3.  However, both history and science have proven time and time again that it is quality and naturalness not quantity that’s important.

As an example, there is a highly concentrated omega-3 fish oil produced by a pharmaceutical company that has an exceptionally high omega-3 content (about 98%). It is registered as a drug and approved by the US FDA for treating high triglycerides. However, recent studies have shown that in addition to reducing triglycerides (which is good), it actually also increases cholesterol levels (which is bad). However, ‘normal’ fish oil lowers both triglycerides AND cholesterol. Obviously, there is some beneficial component of the fish oils that is removed in the highly concentrated oil.

Why is DHA in the spotlight?

DHA (Docosapentaenoic acid) is without a doubt the most complex and beneficial fatty acid as far as the human body is concerned (more so than EPA) as it is a 22 carbon chain bond with six (cis) double bonds. You see, DHA is essential for the growth and functional development of the brain in infants. It is also required for maintenance of normal brain function in adults.

The inclusion of plentiful DHA in the diet improves learning ability, whereas deficiencies of DHA are associated with deficits in learning. DHA is taken up by the brain more readily than any other fatty acid.Other omega-3 fatty acids follow DHA in order of complexity, number of carbon chain bonds and overall efficacy for your body. They are:

  • ·    EPA (Eicosapentaenoic acid) has 20 carbon bonds. It is difficult for the body to convert EPA to DHA because it has to add two carbon bonds. On the other hand the body only has to ‘drop off’ two carbon bonds from DHA to create EPA.
  • ·    ALA (alpha linolenic acid) - commonly found in flaxseed oil, this omega-3 fatty acid only has 18 carbon bonds, making it almost impossible for the body to manufacture DHA from.
  • ·    A special mention must be made with regards to another omega-3 fatty acid – DPA (Docosapentaenoic acid). It acts as the ‘sidekick’ for both DHA and EPA. There has not been a lot of research carried out on DPA; however, it does appear that there are some real benefits associated with DPA because – like DHA - it has 22 carbon bonds.

Pristine and pure

Purity is measured by the amount of heavy metals, PCBs and dioxins present. One simply has to look at the locations where most of the fish oils come from to get a clear idea of why so many omega-3 fish oil products are tainted with toxins.  They are often in the middle of major shipping routes and surrounded by large, heavily populated land masses, where pollution and waste is the inevitable outcome. Other fish oil areas are shared by deep sea oil rigs, hardly the sort of purity perceptions you would want as a customer.

The Southern Ocean is known for its rugged beauty, geographic isolation and unspoiled waters. Located in the ‘roaring 40s’ and ‘raging 50s’, this body of water off the coast of New Zealand is one of the most remote and purest oceans on earth with nothing but open water separating it from South America (over 9 000kms to the east) and Africa (over 10 000kms to the west) - ensuring that it experiences minimal ‘ship traffic’. The entire population of New Zealand is also only a fraction of one major US city – have a look on your atlas to fully appreciate how remote New Zealand really is.

When measuring the purity of fish oil products, four international standards are generally used. Interestingly enough, we at Xtend-Life have set our own specification standards because we don’t think that the normal standards are good enough as they have been set with the fish oil industry in mind rather than the wellbeing of the consumer.

You can view the tough standards we set by going to our website at and going to Omega 3 / DHA Fish Oil and clicking on the purity tab.

There you will find that:

  • ·    Our levels for mercury are 10 times lower than the standards set by international organizations.
  • ·    Our PCB level is set at 18 times lower than the US CRN.  In Europe they don’t even set a minimum level
  • ·    The dioxin levels are also set at a level four times lower.

But, even at these low levels none of these contaminants are detected in our oil – and we can prove it! Have a look at our current Certificate of Analysis which is on our website. We have the independent government-approved laboratory data on file.

Freshness should be your first prize

Freshness is crucial with anything that you put into your mouth. In the case of fish oils, it is even more important as you could be unwittingly adding to your free radical ‘load’ (the very thing you want to combat). Oil which is oxidized is loaded with free radicals and may do you more harm than good.

Keep in mind though that freshness is not just time related, it is how the produce has been handled and looked after since harvesting. For example, a well handled two-day old fish can be even fresher than a one-day fish!

Fishing for freshness

The same senses you use when buying fish from your local fishmonger should also be applied when buying fish oil. This is because your sense of smell and sight are very important when making your purchasing decision.


  • ·    When buying a whole fish, the first thing you should notice are the eyes. Fresh fish that have been handled properly and stored correctly from the boat to the display counter should have big clear eyes. Their gills should mirror the same clarity as the eyes with a bright red lustre and no parasites attached.
  • ·    When buying a fish oil, always look at the supplier’s Certificate of Analysis (COA). The oxidation levels should be as low as possible.


  • ·    Fresh fish should have no ‘fishy’ odours. They should literally smell like the ocean from which they’ve come. Fish that have been handled and stored incorrectly will start to oxidize (decompose) and the resultant smell should send you clear warning signs.
  • ·    Fresh fish oils should also have no rancid odours. Similarly, the fish oil shouldn’t have distinct scents such as lime or any other unnatural fragrance. If it does, then there is no doubt that the supplier is quite aware of the product’s lack of freshness and assumes that this simple ‘scent-mask’ will hide all traces of oxidation. Cut open a fish oil soft gel and put it to the ‘smell’ test.

If these signs haven’t been noticed and common sense hasn’t been followed, then unfortunately – as decomposing fish will no doubt make you sick – oxidized fish oils with rancid odours and/or tastes will almost certainly result in some ‘repeating’ or ‘burping’ at best and an increase in free radical levels at worst. 

How to determine the freshness of your fish oil

It’s important to remind you that freshness is measured by oxidation. Always look out for the total oxidation (TOTOX) value on the supplier’s COA – it is made up of two components:

  • ·    Anisidine value
  • ·    Peroxide value

Some manufacturers in Europe do not publish their anisidine values and although the peroxide values may be reasonable, the overall TOTOX value can be very high. Interestingly, some of them do their testing just for the peroxide value (conveniently after encapsulation and after an elapsed period of time). The peroxide values in a soft gel actually go down over time but the anisidine values go up, therefore pushing the TOTOX value up as well.  It is a trick of the trade that some manufacturers use.

Although the ‘N/A’ indication on the COA may mean ‘Not Available’, it should really mean ‘Not Acceptable’ – don’t be fooled. 

I hope that this article has helped you gain a better understanding of how to select an omega-3 fish oil for yourself and your family. There is a lot of misinformation circulating in the internet about health products. Part of our role is to help ensure that accurate information is available.   If you wish you can obtain more comprehensive information by downloading a free ‘Buyer Guide for Fish Oil’

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About the author


Warren Matthews is the co-founder and Chairman of Xtend-Life Natural Products, a family-owned, integrated manufacturer and distributor of natural supplements and skin care products.

Xtend-Life has since become one of New Zealand's business success stories, renowned for the purity of its ingredients, its innovative formulations and its competitive pricing. The company now sells its expanding range of natural supplements, omega-3 and skin care products each month to thousands of customers in over 40 countries.  

You can read his blog at


Anonymous's picture

Deep sea Fish Oil

Well, you might think that fish that live in the deepest of the waters have more oil and hence, are more suitable for deep sea fish oil production. However, the truth is just the opposite. Researches show that fish that live in the middle waters or near the surface are oilier than those who live in the deepest part of the ocean. Due to the growing water pollution and commercial fishing methods, some species of the fish are becoming extinct day by day. Studies show deep sea fish tend to live around 60-70 years whereas fish that live near the surface enjoy a shorter lifespan. Due to their short lifespan, they do not accumulate harmful contaminants make themselves ideal for deep sea fish oil products. Deep sea fish have higher Omega3 content and are perfect for EPA fish oil products.

Anonymous's picture

EPA Fish oil

This is a very informative post. EPA fish oil is good for health in a number of ways. It mainly takes care of the brain. It controls depression both during and after pregnancy. It also builds the motor skills of the unborn child while still in the mother’s womb. EPA fish oil is thus very effective in passing the messages between the nerve cells of the brain.

Anonymous's picture

Charles Abinante

I thought this post was to show us which fish oil products were the best, but it looks as if it's just another ad for a product that Mr Matthews is pushing! I'm not sure, but I really don't believe that Puritan's Pride is considered one of the best on the market?

Anonymous's picture

L Bluth

Folks, you have referred to both DPA and DHA in the article as docosapentaenoic instead of docosaheptaenoic for DHA (Why is DHA in the Spotlight).

Anonymous's picture


I was enthused at the idea of getting pure, fresh, almost mercury-free, "X-factor" hoki fish oil made by Xtend-Life, even though it is relatively expensive. So I went to their website to buy and discover that half of their fish oil comes from tuna. Disappointing.

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