All Omega-3’s Aren’t Created Equal Part 2 of a 3 Part Series on Omega-3′s
The key to understanding omega-3 fatty acids is that from a nutritional standpoint, all omega-3′s are by no means equal. There are two forms of omega-3′s that exist in nature- long chain and short chain. Strong evidence has found that long chain omega-3′s EPA and DHA (eicosapentaenoic acid and docosahexaenoic acid) have a fundamental role in brain and visual function[1,2], cardiovascular health , reducing inflammation[4,5] and the treatment and prevention of depression and other emotionally based disorders. On the other hand, short chain omega-3′s fatty acids called ALA’s, (alpha linolenic acids) do not have the same health benefits as their long chain cousins but is far more common in nature. (See part one of our series on omega-3′s for a detailed explanation of the differences.) That being said, the possible benefits from consumption of long chain omega-3′s have been significant enough for governmental agencies worldwide to issue advisories to their citizens to increase their intake of fish and seafood as a preventative health care measure. However current labeling laws do not make a clear distinction between the two groups of omega-3 fatty acids, which can be quite confusing for most consumers. This loophole has allowed many food manufacturers to place misleading health claim benefits on the labels of products containing only ALA’s as being good sources of nutritionally beneficial omega-3′s. In this the second of a three part series on omega-3′s, we take an in depth look at the differences between omega-3’s and highlight the drawbacks of relying on foods with artificially added omega-3′s.
Understanding Long Chain Omega-3 Conversion Rates
If you consume most plant sources of omega-3’s your body has to do the conversion from short chain ALA’s to long chain EPA’s and DHA’s and we aren’t designed to do a very good job with such conversions. A study done by the U.S. Department of Agriculture found the conversion efficiency of ALA to DHA in young adult males to be only 4%, while another study found the ratio to be no more than 12% under the best of circumstances.[9,10,11,12,13] Other studies show conversion levels as low as less than 0.1% and it’s a very hard figure to calculate with any degree of precision since conversion rates vary from person to person. For example, women on average tend to have lower conversion rates than men and some people’s bodies seem to do a better job than others. [14,15]
All Omega-3’s In Foods Are Not Created Equal
That being said, while all the health benefits are attributed to the long chain omega-3′s EPA and DHA, many commercially available products labeled as high in omega-3’s don’t contain any of these fatty acids at all. Some contain only short chain omega-3′ (ALA’s) from flaxseed and soybean oils. These short chain omega-3’s are far cheaper and far less volatile than their long chain cousins EPA and DHA, but they do not confer the same health benefits. From a purely profit centered perspective this practice does make sense- long chain omega-3′s are highly oxidative, which means they spoil very quickly at room temperature. As a result they require extensive processing to keep them from turning rancid. Since most long chain omega-3′s come from marine sources there is also the problem of a slightly fishy taste and higher costs incurred from using fish sources as opposed to relatively inexpensive soybeans and flaxseeds. The incentive for misleading consumers is compounded by the fact a health claim benefit on any food product significantly increases its consumer value. This allows manufacturers to charge more for their products while increasing sales at the same time. ALA’s are technically omega-3′s and since there are no federal requirements to differentiate between long chain and short chain omega-3 fatty acids many profit minded corporations see no problem with using ALA’s as an inexpensive way to increase sales and profit margins.
Foods With Artificially Added Omega-3’s Do Not Necessarily Confer Health Benefits
In the absence of government regulation, the only way to know for sure that a product contains long chain omega-3 fatty acids is to look at the ingredient listing. If flaxseed and or soybeans oils are listed but there are no fish sources on the label, you can rest assured that it does not contain any long chain omega-3’s. But even with these so called functional foods where omega-3’s are artificially added some studies have shown that they may not necessarily have a positive impact on your health despite being significantly more expensive. It’s a perplexing finding, as many authorities see omega-3 fortified foods as an easy way to increase the public’s intake of these valuable nutrients for preventative health reasons, especially given the low rates of fish and seafood consumption here in the United States. That being said, such so called functional foods may not be the answer as a Dutch study tracking almost 5,000 patients with histories of heart attacks and cardiovascular disease found that the use of margarine injected with short chain and long chain omega-3 fatty acids had no effect in preventing or reducing the occurrence of heart attacks. The patients consumed on average a total of 18.8 g of omega-3 enhanced margarine per day, which gave them an intake of 226 mg of EPA, 150 mg of DHA, 1.9 g of ALA, or both in the active-treatment groups yet follow-up observations found that consumption of omega-3 fortified margarine had no effect whatsoever in reducing the occurrence of heart attacks. This is even more significant when taking into consideration the fact that patients were also receiving state-of-the-art anti hypertensive, anti thrombotic, and lipid-modifying therapies. A study published in the British Journal of Nutrition found no improvements in cardiovascular health markers even with an average daily intake of 1.4 g EPA+DHA (0.9 g EPA, 0.5 g DHA) from omega-3 fortified foods. What researchers did observe was an increase in body weight due to the use of high calorie processed foods- a weight gain that may have played a part in actually increasing cardiovascular risk factors. It’s a surprising find given the fact that so many studies have shown strong evidence for the role of long chain omega-3’s in preventing cardiovascular events but all such studies used only naturally occurring sources of long chain omega-3’s not artificially added ones- which resulted in higher omega-3 doses as well.[18,19,20] It is not that much of a surprise to anyone with a basic understanding of the history of food supplementation as it is usually the case that our bodies don’t get the same benefits from artificially added compounds as they would from natural sources. We are very much the product of our evolutionary environment and our bodies have adapted to get the most out of foods in natural or minimally processed forms for hundreds of thousands of years. Supplemented nutrition is not always as effective as natural sources.
The other problem we face by adding of omega-3 fats to refined food products is that it takes the focus away from the other unhealthy ingredients they may contain and high calorie content. As we mentioned earlier, omega-3 health claims increase sales and justify higher prices, thus it is no surprise that such fortified foods are a fast growing industry. There were approximately 300 new omega-3 fortified foods introduced in 2006, 400 in 2007 and 700 in 2008 with global sales of omega-3 fortified foods expected to grow from about $5 billion in 2008 to $8 billion in 2012. Breakfast cereals, refined white bread, frozen waffles and so called health bars are as highly processed as foods can get and few would think of them as being even remotely healthy. However, by adding omega-3’s, food manufacturers put a heart healthy stamp of approval on the box which distracts consumers from the reality that the foods they are buying may be high in calories, sugars and fats and contain unhealthy ingredients such as high fructose corn syrup or trans fats. As such you should always be wary of any health claim that focuses your attention on the possible health benefits of a single nutrient or ingredient as opposed to the nutritive properties of the product as a whole. Adding omega-3’s to crack won’t make it any healthier for you and the same goes for most of the growing number of fortified junk foods on the market today.
The Problem With Artificially Fortified Omega-3 Animal Products
Natural sourced foods are not exempt from omega-3 fortification as well. Commercially farmed eggs, for example do not normally contain high levels of long chain omega-3 fatty acids, especially given the shift from natural foraging to seed based feeds high in omega-6 fatty acids (linolenic acid- LA). (See part one of our series on omega-3’s for more information on the effect of modern seed based feeds.) To cash in on the higher sales and profit margins that omega-3 labels can bring, the commercial farming industry have been able to produce eggs containing five to as much as ten times more than the 40 mg of long chain omega-3s that they would normally yield thanks to a diet high in flaxseed oils and fish. Aside from the unnatural occurrence of chickens eating flaxseed and fish, the increased demand for fish feed for chickens creates serious environmental as menhaden is harvested in unsustainable numbers to support the growing fish feed demands. (See part 1 of our series on omega-3’s for a detailed look at the problems caused by menhaden overfishing) Manufacturers don’t care much about environmental costs, just the very tangible reality that adding omega-3’s to eggs enables them to charge as much as four times more than the regular prices. The health claim on eggs also distracts from the fact that eggs are high in cholesterol which has been a public relations nightmare for the industry so it is easy to see how the addition of omega-3’s would provide a much sought after distraction. But is the extra price really worth it when no one can say for sure whether such artificially added omega-3’s confer any real health benefits? In the third and final installment of our series on omega-3’s we take a look at the best sources for long chain omega-3’s and highlight the fact that fish may not be the most natural source for human consumption. Stay tuned.
Read Part 3 of our series on omega-3 fatty acids here:
Read part 1 of our series here:
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