I have been skeptical of supplements for a long period of time. The supplements are generally of low quality, they don’t prevent or cure cancer, they don’t prevent colds, they can’t boost the immune system, and they don’t prevent heart disease. Now it’s the time to take a look at the benefits of omega 3 fish oil, something that is claimed by Big Supplement over and over. Is there anything there?
Unless one has a chronic disease or is chronically malnourished, there are precious few instances where supplements are necessary. A couple of cases where supplements may be critical include prenatal folic acid supplements to prevent neurological defects in the developing fetus and vitamin D supplements for individuals who do not produce enough endogenous vitamin D. However, just to keep this in perspective, excess folic acid for a long period of time may be correlated with increased rates of certain cancers.
The benefits of omega 3 fish oil has always been intriguing to me, because it is a supplement that I thought might be useful to improving health, especially cardiovascular health. Omega 3 fatty acids are generally found in fish, as it is produced by the phytoplankton that is the primary food source of much of the prey for larger fish and bio-accumulates up the food chain. However, for humans, there are other sources of omega 3 oils including walnuts and edible seeds, eggs, and other non-fish foods.
Epidemiological studies done in the late 1980s seem to indicate relatively low death rates due to cardiovascular disease in Inuit populations with high seafood consumption. These results began the rush to consume omega 3 supplements, and created a booming supplement industry.
However, since publication of those initial studies, much research has been done on seafood and heart disease. And the results don’t give much credence to the cardiovascular benefits of omega 3 fish oils as a useful supplement.
The science of omega 3 fatty acids
Omega 3 fatty acids are considered one of the “essential’ fatty acids” because they are important to normal growth in young children and animals, and because humans (and many other mammals) cannot produce omega 3 fatty acids within the body and need to consume it. Generally, humans consume adequate amounts of the fatty acid, and only rarely are cases of deficiency found.
There are three principal omega-3 fatty acids: alpha-linolenic acid (ALA), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA). The main sources of ALA in the U.S. diet are vegetable oils, particularly canola and soybean oils. ALA can be converted, usually in small amounts, into EPA and DHA in the body. EPA and DHA are found in seafood, including fatty fish (trout, salmon and tuna) and shell fish (including crabs, lobsters, clams and mussels).
Without getting into a lot of complex biochemistry, omega 3 oils are converted by various organs into key agents that are necessary for development and for regulating some aspects of the immune response. For example, omega 3 fatty acids are converted by enzymes into what are now known as eicosanoids–thromboxanes, prostacyclins, and the leukotrienes. Eicosanoids, which have numerous biological functions such as wound repair, typically have a short lifespan in the blood–they are quickly metabolized by enzymes. However, if the rate of synthesis exceeds the rate of metabolism, the excess eicosanoids may be dangerous.
Omega-3 fatty acids are important for a number of bodily functions, including muscle activity, blood clotting, digestion, fertility, and cell division and growth. Specifically, DHA is important for brain development and function.
Once again, just because a little bit of omega 3 in the diet may be good, it’s possible that excess amounts may not be. One of the major myths of the supplement industry is “if a little is good, a lot is better.” There is an assumption that the body is so weak that it constantly needs to be given omega 3 fatty acids or any other supplement to survive. Well, that’s just not supported by science.
Benefits of omega 3 fish oil
Infant development–Though I can be convinced that there are some occasions where omega 3 supplementation, specifically DHA, might be important, such as for young children. The nutritional value of seafood is particularly important during early development. The Dietary Guidelines recommend that women who are pregnant or breastfeeding consume at least 8 ounces but no more than 12 ounces of seafood each week and not eat certain types of seafood that are high in methyl mercury—a toxin that can harm the nervous system of a fetus or young child. The recommendation includes consuming seafood, not supplements.
Rheumatoid arthritis–A 2012 systematic review concluded that the types of omega-3s found in seafood and fish oil may be modestly helpful in relieving symptoms of rheumatoid arthritis. The review of 23 studies concluded that “a fairly consistent, but modest, benefit of (omega 3 fish oils) on joint swelling and pain, duration of morning stiffness, global assessments of pain and disease activity, and use of non-steroidal anti-inflammatory drugs.” The benefits are just on the border of clinically significant, and will not reverse the course of the disease, but it may be helpful.
Heart disease–Most people take the supplement to prevent heart disease. But what does the science say after nearly 30 years since that initial epidemiological study was done with Inuit populations?
There have been several studies that have evaluated the potential benefits of omega 3 fish oil supplements, which are rich in EPA and DHA, on heart disease risk. These studies compared the number of cardiovascular events (such as heart attacks or strokes) or the number of deaths in people who were given the supplements with those in people who were given placebos or standard cardiovascular care.
The results of individual studies were inconsistent with a range of results from clinically useless to somewhat useful. In 2012, two separate meta-analyses (the best kind of evidence available) of these studies were published–the first one analyzed only those studies which included individuals with a history of heart disease, and the other one analyzed studies of individuals both with and without a history of heart disease. Neither meta-analysis found convincing evidence of protective benefits for omega 3 fish oil supplementation.
There are several reasons why omega 3 supplements, even ones rich in EPA and DHA, may not help to prevent heart disease even though a diet rich in seafood that contains the fatty acid may actually have a benefit. Eating seafood frequently might provide enough of these omega 3s to protect the heart–however, more omega 3 may not be better.
Moreover, some of the benefits of seafood may result from people eating it in lieu of other, less healthful, foods. There is also some evidence that individuals who eat seafood have generally healthier lifestyles, which may be responsible for the lower incidence of cardiovascular disease.
There are some ongoing clinical trials that are attempting to separate out the clinical “noise” in cardiovascular issues to determine if omega 3 fish oil supplements may help. But we’re years away from any meaningful data, and it would be surprising if this data showed any meaningful clinical data superior to what we know now.
Other claims–Omega 3 fish oil supplements also have been claimed to prevent or treat other conditions–allergies (meta review says no), asthma (research says no), Crohn’s disease (ineffective), cystic fibrosis (no useful clinical data according to meta-review), kidney disease (no solid clinical evidence), lupus (no evidence), obesity (no evidence), osteoporosis (no conclusive clinical evidence), and ulcerative colitis (no evidence),
In general, there is no conclusive or, in some cases, negative evidence regarding the benefits of omega 3 fish oil for most health conditions. In fact, even the annoying and wasteful National Center for Complementary and Integrative Health, which pushes junk medicine under the guise of the National Institutes of Health, provides a fairly negative review of the benefits of omega 3 fish oil.
One reason to not use omega 3 fish oils
Most omega 3 fish oils are processed from one type of fish–menhaden, which are a key part of the food chain in the ocean. The highly oily fish (which gives us the omega 3 fatty acids) consumes and redistributes a significant amount of energy within and between Chesapeake Bay and other estuaries, and the coastal ocean (see The Most Important Fish in the Sea: Menhaden and America). Menhaden are not generally eaten by humans, although they had an important role in fertilizing crops in early America.
The problem has become that fish oil processors harvest over 500 million menhaden a year, and has caused a drop in the population of the fish. Because they are an invaluable prey species for many predatory fish (which are also important game and commercial fishes) such as striped bass, bluefish, mackerel, flounder, tuna, Drum (fish), and sharks. They are also a critical food source for many avian species including egrets, ospreys, seagulls, northern gannets, pelicans, and herons.
In 2012 the Atlantic States Marine Fisheries Commission declared that the menhaden stocks had become depleted because of overfishing, almost all of which was used to manufacture omega 3 supplements for people who consume them with few health benefits. Some important predator species populations have crashed due to lack of menhaden on which they could feed.
So if you believe that taking your supplements may help you, and think that it does no harm–well, you’d be wrong.
If you need omega 3 fish oils–eat fish. The predator species, like salmon and tuna, have very high amounts of omega 3 fish oils. And consuming fish may lead to a healthier diet and lifestyle which will have a better impact on medical concerns like cardiovascular disease.
And to consume a supplement that has a such a destructive effect on our ocean’s environment to gain no benefit? That’s just ridiculous.
Why is it that people think that there are simple panaceas to life? Take an omega 3 capsule and declare to the world that you’re healthier? And do that with no concern about the environment around you.
The omega 3 fish oil industry has grown to over $1.2 billion in sales in the USA (thank you for destroying the fish stocks) based on false and unproven claims. I won’t even mention the laughable belief that somehow the Big Supplement is the epitome of good morals and ethics.
Most supplements are ridiculous. If someone wants to take echinacea because they believe it will cure a cold, that’s their problem and their money. But omega 3s? Different story. Stop taking it, unless you have a very specific medical condition. Stop it. You’re destroying the environment.
Note: two papers that were highly critical of fish oil’s health effects were recently retracted. The papers, by Brian Peskin, were not against omega 3, but attempted to show that omega 3 effects were better when from plant based oils. The retractions were based upon two key points:
- The journal classified the papers were marked as including “Unreliable findings,” and “Biased interpretation.”
- The journal stated that the “Results of publication” are “invalid.”
I never cited those studies nor used them in this article, because I thought they were biased, though I didn’t think it was this bad.
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