Are Some Omega-3 Fish Oil Supplements Better Than Others?

Written by Dr. Steve Chaney on . Posted in current health articles, Omega-3 Fish Oil Supplements

Author: Dr. Stephen Chaney

truth about omega-3 fish oil supplementThe ethyl ester form of omega-3 fatty acids from fish oil has been the industry standard for high purity omega-3 fish oil supplements for many years. It is very stable, easily purified, and well absorbed by the body. What’s not to like?

If you believe some recent advertisements, there is a lot not to like about the ethyl ester form of omega-3s. These ads each claim that their particular form of omega-3s is more natural, better absorbed, and more efficiently incorporated into cell membranes, or some combination of those features. They each cite clinical studies “proving” that their products are superior. These advertisements seem so plausible and so compelling.

However, most of these advertisements come from relatively new companies that are trying to make a name for themselves in a very profitable and competitive product niche. Are the advertisements true, or is it all just smoke and mirrors? Most of these advertisements rate at least one Pinocchio.

However, it is almost impossible to tell you why I consider these advertisements omega-3 fish oil supplements to be misleading without getting a little “techie”, so let’s start with some basic definitions. I call this section “Omega-3s 101.”

 

Omega-3s 101

 

Let’s start with some basic definitions:

  • Free fatty acids (FFA) are long chain hydrocarbons with a single acid group at the end. They are only slightly water soluble. They are important intermediates in metabolism, but they are almost always combined with something else in the body.
  • Saturated fatty acids contain no double bonds, monounsaturated fatty acids contain one double bond, and polyunsaturated fatty acids contain multiple double bonds. The number of double bonds primarily affects whether they are liquids (polyunsaturated) or solids (saturated) at room temperature.
  • omega-3 fatty acidsThere are two classes of polyunsaturated fatty acids that are essential because the body cannot make them. Those with a double bond 3 carbons from the end are called omega-3s(If you think about the Greek alphabet, omega is at the end). Those with a double bond 6 carbons from the end are called omega-6s.
  • When 3 fatty acids are combined with a single molecule of glycerol they form very water insoluble compounds commonly referred to as fats or triglycerides. The proper chemical name is triacylglycerol, which is abbreviated TAG.
  • If one of the fatty acids on the glycerol chain is replaced by a compound containing phosphate and other charged residues, the resulting complex is called a phospholipid (PL). Because these compounds have a hydrocarbon surface that is attracted to fats and a highly charged surface that is attracted to water, they are good at emulsifying fats and are an important part of membrane structure. One phospholipid that is a major component of membranes is called phosphatidylcholine (PC), also known as lecithin.

Next, let’s look at how omega-3 fatty acids are metabolized:

  • The omega-3s in fish oil are primarily in the form of triglycerides, with small amounts of phospholipids. The omega-3s in most omega-3 supplements are in the form of ethyl esters for the reasons stated above.
  • Before the omega-3s leave the intestine they are hydrolyzed to free fatty acids.
  • In the cells that line the intestine the omega-3s are reconverted back into triglycerides and phospholipids and incorporated into special lipid-protein complexes for transport through the blood.
  • Once these lipid-protein complexes reach our cells, their contents are delivered to the cell where they can be stored as fat (TAG), used for energy (FFA), or incorporated into membranes (PL). It is primarily the omega-3s incorporated in cellular membranes that are thought to be responsible for the beneficial effects of omega-3s.

Finally, we should ask how one measures the bioavailability of the various forms of omega-3s:

While there are some nuances that I did not cover, the basic mechanisms of absorption and metabolism of omega-3s are remarkably similar regardless of whether they start out in the ethyl ester, triglyceride, phospholipid, or free fatty acid form. The questions then become, how does one test how efficiently the various forms are utilized by the body and how much do these individual test actually tell us?

  • When we look at what happens in the bloodstream, we need to be aware that we are looking at a combination of two effects – how rapidly the substance enters the bloodstream and how rapidly it leaves from the bloodstream. There are three important parameters we can measure when looking at delivery of omega-3s to the bloodstream:
    • The maximum concentration achieved (Cmax)
    • How rapidly that maximum concentration was achieved (Tmax)
    • The total amount in the bloodstream over time (AUC)
  • When you look at some of the ads touting specialized forms of omega-3s, they are usually based on studies looking at either the maximum levels of omega-3s in the bloodstream (Cmax) or how rapidly those maximum levels were achieved (Tmax). (One suspects the ads may have selectively featured whichever parameter made their product look best). However, the parameter that really matters is the total concentration of omega-3s achieved over time (AUC).
  • Finally, the most important question is how much of the omega-3 is actually incorporated into cellular membranes. Once again, there is more than one parameter that can be measured.
  • One can measure the level of omega-3s found in cellular membranes in a short term study (a few hours) or in a long term study following many weeks of supplementation.
  • The short term studies only measure the rate of incorporation. The long term studies measure the steady state levels attained over time, which is a much more relevant measure.
  • Once again, the ads touting specialized products are usually based on short term studies which are really measuring an initial rate of incorporation of omega-3s into cellular membranes, not on long term studies that measure the steady state level of omega-3s achieved over time.

 

Are Some Omega-3 Fish Oil Supplements Better Than Others?

omega-3 fish oil supplementThere has been a lot of confusion in the literature about whether the form of omega-3 supplements matters. Various studies have been published supporting the superiority of one form or another of omega-3s. Most of these studies have been supported by manufacturers who have a particular form of omega-3s they want to sell, and, as I mentioned above, the parameters tested seem to have been selected to make their supplement look good.  So, are some omega-3 fish oil supplements better than others?

 

Finally, someone has designed a comprehensive study to clear up all the confusion and provide answers that can be trusted (West et al, British Journal of Nutrition, 116: 788-797, 2016). Interestingly, this research was supported by a pharmaceutical company (Vifor Pharma) that does not appear to sell an omega-3 product currently. Perhaps they simply wanted to find out what worked best before designing their own product. What a novel concept!

The authors tested 4 different forms of omega-3 fish oil supplements:

  • Unmodified fish oil containing the omega-3s primarily in triglyceride form (uTAG).
  • An omega-3 supplement in which the omega-3s in the fish oil had been hydrolyzed to free fatty acids (FFA).
  • An omega-3 supplement in which the omega-3s in the fish oil had been hydrolyzed to free fatty acids and converted back to triglycerides (TAG)
  • An omega-3 supplement in which the omega-3s in the fish oil had been hydrolyzed to free fatty acids and converted to ethyl esters (EE)

All 4 supplements contained 1.1 grams of EPA and 0.37 grams of DHA.

The authors conducted two studies:

  • One was a cross-over study where healthy men consumed each of the supplements in random order on different days with 14 days between tests. Blood samples were collected over the next 6 hours and levels of EPA and DHA in the blood and cellular membranes was determined.
  • The other was a long term study in which a randomized group of healthy men and women consumed one of the supplements for 12-weeks and incorporation of the EPA and DHA into cellular membranes was measured.

The results were pretty clear cut:

  • In the short term study there were no significant differences between the various supplements in the rate of uptake, maximum concentration achieved, or the total concentration over time when uptake of omega-3s into plasma triglycerides and phospholipids was measured.
  • The ethyl ester form was less efficiently incorporated into plasma free fatty acids than the other forms as reported in some previous studies, but this is perhaps the least important parameter measured, and there was large variability from subject to subject.
  • In the long term study, no significant differences were seen between the various supplements in omega-3 incorporation into cellular membranes.

The authors concluded: “Together, these findings show that in healthy individuals neither the lipid structure nor the overall fatty acid composition of supplements influence their bioavailability during dietary supplementation, despite the apparent lower postprandial availability [in short term studies] of EPA + DHA ethyl esters compared with triglycerides or free fatty acids.”

What Do These Studies Mean For You?

You can forget all those ads hyping the newest, greatest form of omega-3 fish oil supplements. Objective research has shown there is not a dimes worth of difference between the various forms of omega-3 supplements.

A far more important question is the purity of the omega-3 supplement you are using. Purity of omega-3 supplements is a huge issue. You need to remember that the EPA + DHA supplements you purchase come from polluted fish. Unfortunately, many manufacturers have inadequate purification and quality control standards. In other words, neither you nor they know whether their omega-3 products are pure. You need to make sure that the omega-3 supplement you purchase is made by a manufacturer with stringent quality control standards.

Sustainability is also an issue, so you should choose manufacturers who source their omega-3s in a sustainable manner. There are two comments I will make about sustainability so you won’t be misled.

  • Krill oil is marketed as a more sustainable source of omega-3s. Krill reserves are quite large, but they are not infinite. Krill is also the very foundation of the food chain that supports a large percentage of our ocean’s fish. We need to be very cautious about depleting our krill reserves.
  • Omega-3s derived from algae are also marketed as a more sustainable source of omega-3s. Algae-derived omega-3s have purity issues of their own, but may become an important source of omega-3s once those issues have been resolved.

 

The Bottom Line

  • The ethyl ester form of omega-3 fatty acids from fish oil has been the industry standard for high purity fish oil supplements for many years. It is very stable, easily purified, and well absorbed by the body.
  • However, in recent years, some manufacturers have been claiming that their omega-3 fish oil supplements were better utilized by the body because their supplements contained the omega-3s in triglyceride or free fatty acid forms.
  • Unfortunately, the clinical studies supporting those claims have been supported by the manufacturers making the products. There is reason to suspect that the data has been “cherry picked” to support the conclusions that support the manufacturer’s claims.
  • Finally, an independent and comprehensive study has compared the various forms of omega-3 fatty acids. It found that neither the lipid structure nor the overall fatty acid composition of omega-3 supplements influenced their bioavailability during long term dietary supplementation.
  • A far more important question is the purity of the omega-3 supplement you are using. Purity of omega-3 supplements is a huge issue. You need to remember that the EPA + DHA supplements you purchase come from polluted fish. Unfortunately, many manufacturers have inadequate purification and quality control standards. In other words, neither you nor they know whether their omega-3 products are pure. You need to make sure that the omega-3 supplement you purchase is made by a manufacturer with stringent quality control standards.

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  • Peggy Shearin

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    very, very interesting..

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Latest Article

Is Coconut Oil Bad For You?

Posted July 25, 2017 by Dr. Steve Chaney

Nutty About Coconut Oil

Author: Dr. Stephen Chaney

is coconut oil bad for youCoconut oil is the latest miracle food. Bloggers and talk show hosts are telling us how healthy it is. We are being told to cook with it, spread it on our toast, and put it in our smoothies. We are told to be creative. The more coconut oil you can get in your diet, the better.  But, is coconut oil bad for you?

The hype is working. 72% of the American public believes coconut oil is healthy. This is why the recent American Heart Association (AHA) Presidential Advisory on saturated fats has proven so controversial.

Interestingly, most of the AHA advisory was about the linkage between saturated fats from meat & dairy and heart disease risk. Only one paragraph of the 24-page report was devoted to coconut oil, but the AHA recommendation to avoid coconut oil generated the lion’s share of headlines.

What Did The AHA Presidential Advisory Say?

The AHA advisory concluded that saturated fats from meat and dairy foods increased the risk of heart disease. This conclusion was based on randomized clinical trials in which the diet was carefully controlled for a period of at least two years. More importantly, the conclusion was not based on LDL cholesterol, particle size, HDL cholesterol, inflammation or any other potential marker of heart disease risk. It was based on actual cardiovascular outcomes – heart attacks, strokes, deaths due to heart disease.

I have reviewed the AHA report in a previous issue of “Health Tips From the Professor,” Are Saturated Fats Bad For You, and have concluded their statement that saturated fats from meat and dairy increase the risk of heart disease was based on solid evidence. We can now say definitively that those saturated fats should be minimized in our diets.

 

Is Coconut Oil Bad For You?

 

coconut oil bad for heartIn contrast to the saturated fats in meat and dairy, there have been no studies looking at the effect of coconut oil on cardiovascular outcomes. Instead, the authors of the AHA report relied on studies measuring the effect of coconut oil on LDL cholesterol levels. There have been 7 controlled trials in which coconut oil was compared with monounsaturated or polyunsaturated oils.

  • Coconut oil raised LDL cholesterol in all 7 studies.
  • The increase in LDL cholesterol in these studies was identical to that seen with butter, beef fat, or palm oil.

This evidence makes it probable that coconut oil increases the risk of heart disease. However, LDL is not a perfect predictor of heart disease risk. The only way to definitively prove that coconut oil increases the risk of heart disease would be to conduct clinical studies in which:

  • Coconut oil was substituted for other fats in the diet.
  • All other dietary components were kept the same.
  • The study lasted at least 2 years.
  • Adherence to the “coconut oil diet” was monitored.
  • Cardiovascular outcomes were measured (heart attack, stroke, death from heart disease).

In short, one would need the same type of study that supports the AHA warning about saturated fats from meats and dairy. In the absence of this kind of study, there is no “smoking gun.” We cannot definitively say that coconut oil increases the risk of heart disease.

Is Coconut Oil Healthy?

coconut oil healthyDoes that mean all those people who have been claiming coconut oil is a health food are right? Probably not. At the very least, their health claims are grossly overstated.

Let’s start with the obvious. In the absence of any long-term studies on the effect of coconut oil on cardiovascular outcomes, nobody can claim that coconut oil is heart healthy. It might be, but it might also be just as bad for you as the saturated fats from meat and dairy. It’s effect on LDL cholesterol suggests it might increase your risk of heart disease, but we simply do not know for certain.

I taught human metabolism to medical students for 40 years. I was also a research scientist who published in peer reviewed journals. When I look at the health claims for coconut oil on the internet, I am dismayed. Many of the claims are complete nonsense. Others sound plausible, but are based on an incomplete understanding of human metabolism. None of them would pass peer review, but, of course, there is no peer review on the internet.

In addition, some of the claims have been “cherry picked” from the literature. For example, claims that coconut oil increases metabolic rate or aids weight loss are based on short-term studies and ignore long-term studies showing those effects disappear over time.

Let me review some of the more plausible-sounding claims for coconut oil.

  • Coconut oil increases HDL levels, which is heart healthy. The effects of HDL cholesterol are complex. Elevated HDL levels are not always heart protective.

For example, a few years ago a pharmaceutical company developed a drug that raised HDL levels. They thought they had a blockbuster drug. You didn’t need to exercise. You didn’t need to lose weight. You would just pop their pill and your HDL levels would go up. There was only one problem. When they did the clinical studies, their drug had absolutely no effect on heart disease risk. It turns out it is exercise and weight loss that reduce heart disease risk, not the increase in HDL associated with exercise and weight loss.

The implications are profound. Just because something increases HDL levels does not mean it will reduce cardiovascular risk. You have to actually measure cardiovascular risk before claiming something is heart healthy. That has not been done for coconut oil, so no one can claim it is heart healthy.

  • Coconut oil consists of medium chain triglycerides, which are absorbed more readily than other fats. That is true, but it is of interest to you only if you suffer from a fat malabsorption disease. Otherwise, it is of little importance to you.
  • Medium chain triglycerides are preferentially transported to the liver, where the fats in coconut oil are converted to energy or released as ketones rather than being stored as fat. This is partially true, but it is misleading for two reasons.
    • First, the fat in coconut oil actually has three possible fates in the liver. Some of it will be converted to energy, but only enough to meet the immediate energy needs of the liver. If carbohydrate is limiting, the excess will be converted to ketones and exported to other tissues as an energy source. If carbohydrate is plentiful, the excess will be converted to long chain saturated fats identical to those found in meat and dairy and exported to other tissues for storage.
    • Secondly, nobody has repealed the laws of thermodynamics. If the fat in coconut oil is being preferentially used as an energy source by the liver and being exported as ketones to other tissues as an energy source, you need to ask what happens to the calories from the other components in your diet. If you are eating a typical American diet, the carbohydrate that would have been used for energy will be converted to fat and stored. If you are eating a low carbohydrate diet, the other fats that would have been used for energy will simply be stored. Simply put, if you are preferentially using the calories from coconut oil for energy, the calories from the other foods in your diet don’t just evaporate. They are stored as fat.
  • Coconut oil increases metabolic rate, which will help you lose weight. When you look at the studies, this is only a temporary effect. This is due to a phenomenon called metabolic adaptation that is often seen when one makes a dramatic shift in diet composition. Initially, you may see an increase in metabolic rate and weight loss. After a few weeks, the body adapts to the new diet,and your metabolic rate returns to normal.
  • Coconut oil is metabolized to ketones which have many beneficial effects. There is some truth to this claim. As I discussed in my analysis of the keto diet,  ketones have some real benefits, but not nearly as many as proponents claim. Furthermore, the amount of ketones produced by coconut oil will depend on the availability of carbohydrate. Much of the coconut oil in the context of a very low carbohydrate diet will likely be converted to ketones. Coconut oil spread on a piece of bread or used in baking is more likely going to be converted to fat.

I could go on, but you get the point. The hype about the benefits of coconut oil sounds good, but is misleading. There may be some benefits, but in the absence of long-term studies we have no convincing evidence that coconut oil is good for us.

What Does This Mean For You?

coconut oil bad or goodWhen you started reading this article, you were probably hoping that I would settle the coconut oil controversy. Perhaps you were hoping that I would tell you the American Heart Association was right, and you should avoid coconut oil completely. More likely you were hoping I would tell you the coconut oil proponents were right and you could continue looking for more ways to incorporate coconut oil into your diet. As usual, the truth is somewhere in between.

Coconut oil may increase our heart disease risk, but the evidence is not definitive. We cannot say with certainty that coconut oil is bad for us. On the other hand, most of the hype about the benefits of coconut oil is inaccurate or misleading. We have no well-designed, long-term studies on health outcomes from coconut oil use. We cannot say with certainty that coconut oil is good for us.

I recommend moderation. Small amounts of coconut oil are probably alright. If you have a particular recipe for which coconut oil gives the perfect flavor, go ahead and use it. Just don’t add it to everything you eat.

Finally, there are other oils we know to be healthy that you can use in place of coconut oil. If you are looking for monounsaturated oils, olive oil and avocado oil are your best bets. Olive oil can be used in salads and low temperature cooking. Avocado oil is better for high temperature cooking. Also, less frequently mentioned, safflower and sunflower oils are also good sources of monounsaturated fats.

If you are looking for a mixture of monounsaturated and polyunsaturated fats, safflower oil, canola oil and peanut oil are your best bets. Peanut oil is also good for high temperature cooking.

Corn oil and soybean oil are your best sources of omega-6 polyunsaturated fats, while flaxseed oil is your best vegetable source of omega-3 polyunsaturated fats.

 

The Bottom Line

 

  • Coconut oil is the latest diet fad. It is highly promoted by the popular press, and 72% of Americans think it is healthy, even though it is a saturated fat.
  • The American Heart Association (AHA) has recently advised against the use of coconut oil because it likely increases the risk of heart disease and “has no offsetting beneficial effects.”  Because this statement is controversial, I have carefully analyzed the pros and cons of coconut oil use.
  • Coconut oil may increase our heart disease risk, but the evidence presented by the American Heart Association is not definitive. We cannot say with certainty that coconut oil is bad for us.
  • On the other hand, most of the hype about the benefits of coconut oil is inaccurate or misleading. We have no well-designed, long-term studies on health outcomes from coconut oil use. We cannot say with certainty that coconut oil is good for us.
  • I recommend moderation. Small amounts of coconut oil are probably alright. If you have a particular recipe for which coconut oil gives the perfect flavor, go ahead and use it. Just don’t add it to everything you eat.
  • For details of my analysis and suggestions for healthy fats you can substitute for coconut oil, read the article above.

 

These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure or prevent any disease.

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