Excess omega-3 fatty acids could lead to negative health effects, says a recent study from Oregon State University, according to the October 28, 2013 news release, "Excess omega-3 fatty acids could lead to negative health effects." A new review suggests that omega-3 fatty acids taken in excess could have unintended health consequences in certain situations, and that dietary standards based on the best available evidence need to be established. The ratio of omega 3, 6, 7, and 9 each have different ratios that achieve a healthy, normal balance in the human body. And each person is different in genetic needs when it comes to fats and the amount needed for optimum health.
"What looked like a slam dunk a few years ago may not be as clear cut as we thought," said Norman Hord, according to the news release. Hord is an associate professor in Oregon State University (OSU's) College of Public Health and Human Sciences and a coauthor on the paper. "We are seeing the potential for negative effects at really high levels of omega-3 fatty acid consumption. Because we lack valid biomarkers for exposure and knowledge of who might be at risk if consuming excessive amounts, it isn't possible to determine an upper limit at this time."
Previous research led by Michigan State University's Jenifer Fenton and her collaborators found that feeding mice large amounts of dietary omega-3 fatty acids led to increased risk of colitis and immune alteration.
Those results were published in the journal Cancer Research in 2010. As a follow-up, published online in the journal Prostaglandins, Leukotrienes and Essential Fatty Acids, also known as (PLEFA), Fenton and her co-authors, including Hord, reviewed the literature and discuss the potential adverse health outcomes that could result from excess consumption of omega-3 fatty acids. Studies have shown that omega-3s, also known as long chain polyunsaturated fatty acids (LCPUFAs), are associated with lower risk of sudden cardiac death and other cardiovascular disease outcomes. "We were inspired to review the literature based on our findings after recent publications showed increased risk of advanced prostate cancer and atrial fibrillation in those with high blood levels of LCPUFAs," Fenton said, according to the news release.
Omega-3 fatty acids have anti-inflammatory properties, which is one of the reasons they can be beneficial to heart health and inflammatory issues, but beware of excess levels of omega-fatty acids.
The researchers said excess amounts of omega-3 fatty acids can alter immune function sometimes in ways that may lead to a dysfunctional immune response to a viral or bacterial infection. "The dysfunctional immune response to excessive omega-3 fatty acid consumption can affect the body's ability to fight microbial pathogens, like bacteria," Hord said in the news relase.
Generally, the researchers point out that the amounts of fish oil used in most studies are typically above what one could consume from foods or usual dosage of a dietary supplement. However, an increasing amount of products, such as eggs, bread, butters, oils and orange juice, are being "fortified" with omega-3s. Hord said this fortified food, coupled with fish oil supplement use, increases the potential for consuming these high levels.
"Overall, we support the dietary recommendations from the American Heart Association to eat fish, particularly fatty fish like salmon, mackerel, lake trout or sardines, at least two times a week, and for those at risk of coronary artery disease to talk to their doctor about supplements," he said, according to the news release.
"Our main concern here is the hyper-supplemented individual, who may be taking high-dose omega-3 supplements and eating four to five omega-3-enriched foods per day," Hord added. "This could potentially get someone to an excessive amount. As our paper indicates, there may be subgroups of those who may be at risk from consuming excess amounts of these fatty acids."
Hord said there are no evidence-based standards for omega-3 intake and no way to tell who might be at health risk if they consume too high a level of these fatty acids
"We're not against using fish oil supplements appropriately, but there is a potential for risk," Hord said in the news release. "As is all true with any nutrient, taking too much can have negative effects. We need to establish clear biomarkers through clinical trials. This is necessary in order for us to know who is eating adequate amounts of these nutrients and who may be deficient or eating too much. "Until we establish valid biomarkers of omega-3 exposure, making good evidence-based dietary recommendations across potential dietary exposure ranges will not be possible."
Sanjoy Ghosh from University of BC-Okanagan, Canada and Eric Gurzell from Michigan State University also contributed to this study, which was supported by grants from the National Institutes of Health and the Canadian Diabetes Association.
Anti-inflammatory effects of omega 3 fatty acid in fish oil linked to lowering of prostaglandin
In the April 4, 2006 Federation of American Societies for Experimental Biology news release , "Anti-inflammatory effects of omega 3 fatty acid in fish oil linked to lowering of prostaglandin," omega 3 fatty acids in dietary fish oil are reported to have anti-inflammatory and anti-thrombogenic and anti-arrhythmic effects in humans, but the biochemical basis for these beneficial health effects is not well understood. Now a University of Michigan biochemist reports that fish oil significantly diminishes the production and effectiveness of various prostaglandins, naturally occurring hormone-like substances that can accentuate inflammation and thrombosis. Dr. William L. Smith described his findings on April 4, 2006 at Experimental Biology 2006 in San Francisco. His presentation was part of the scientific program of the American Society for Biochemistry and Molecular Biology (ASBMB).
Dietary fish oil causes its prostaglandin-lowering effects through three different mechanisms, says Dr. Smith, according to the news realease
First, the much fewer prostaglandins are made from omega 3 fatty acids as compared to the other class of fatty acids in the body, the omega 6 family of fatty acids that originate in the diet from leafy vegetables and other plant sources. Second, the omega 3 fatty acids compete with omega 6 fatty acids for the same binding site on the COX 1 enzyme that converts the omega 6 fatty acids to prostaglandin (which is why the COX 1 enzyme and its COX 2 cousin are the targets of anti-inflammatory drugs like ibuprofen). The more omega 3 fatty acids present to block the binding sites, the fewer omega 6 fatty acids are able to be converted to prostaglandin. Third, although omega 3 fatty acids also are converted to prostaglandins, the prostaglandins formed from omega 3 are generally 2 to 50 times less active than those formed from the omega 6 fatty acids from dietary plants.
What omega 3 fatty acids impact in the human body
The biochemical basis of other benefits of dietary fish oil – for example, omega 3 fatty acids' impact on neuronal development and visual acuity -- are probably due to effects on biochemical pathways regulating nerve transmission. Understanding the different pathways through which omega 3 works to convert prostaglandin helps explain why the plant-based omega 6 fatty acids don't simply provide the same benefits.
Because of omega 3 fatty acids' known benefits to health, especially cardiovascular health, Dr. Smith's advice is simple: eat more fish. But the problem may be with excess omega 3 fatty acids when so many foods are supplemented with it, and the person takes omega 3 supplements, and eats foods such as an excess amount of flax seed meal, all types of fish oils, or other sources and the omega-6 fatty acids build up in the body. An individual may be cutting out other omega oils in foods or supplements. That's an issue scientists continue to study. The goal is to achieve the correct ratios of fatty acids that nature intended for each person's individual genetic and metabolic needs, fatty acids such as omega 3, 6, 7, and 9 in the correct ratio for balance and ideal health.
How hazardous to your health is excess omega 6 fatty acids?
What can excess omega 6 do to your immune system? Are you eating lots of peanut butter, for example, because you read it might control your blood glucose levels along with cinnamon, but now find you have worsened gum disease from eating excess omega 6? Perhaps you need to balance omega 6 with omega 3 and omega 9 in portions that are best tailored to your own health needs?
You might check out some of the books by John Yudkin, T.L. Cleave, and others about how much or little omega-6 seed oils you need to keep that balance. After all, even olive oil touted as healthy has omega 6 fatty acids. Then ask yourself why cultures consuming lots of fresh pressed, cold pressed, expeller pressed extra virgin olive oil seem to be healthy. What else are they eating to keep their diet in balance? Perhaps lots of omega 3 fatty acids and omega 9 fatty acids?
The edible oils industry must have a lot of commercial, academic, and political clout because there seems to be somewhat of a general, popular consumer magazine media blackout now and then regarding the harmful effects of excessive omega-6 consumption. For example, see, "Case Study: 30-Days of high Omega-6 Diet -- Stiffens Arteries and Increases Belly Fat." As registered dietitian, Evelyn Tribole (M.S. R.D.) notes, "Oprah magazine paid for the study and article but declined to publish the results," according to that article. In that July 25, 2010 article, a daring journalist ate a high omega-6 diet for 30-days (think Super-Size Me), which resulted in stiffer arteries.
In the article, the woman eating a 30-day diet including a specific amount of omega 6 fatty acids didn't have any changes in her weight. But the changes occurred in the fatty acid composition of her bloodstream, body fat, arterial function, and body mass composition, according to that article. Basically, just by increasing omega 6 fatty acids and decreasing omega 3 fatty acid, the changes took place. Check out that article on how too much omega 6 fatty acids increases belly fat and stiffens arteries.
Now check out Consumer Reports on Health. Did you ever wonder why there's so few mentions of omega 6 fatty acids? Although there are a number of articles about the therapeutic benefits of omega-3s, where's the mention of omega-6? This is strange because as early as 1999 National Institutes of Health scientists were recommending reduced intake of omega-6s to increase the effectiveness of omega-3s.
You need to reduce excess consumption of omega 6 polyunstaturated fatty acids (also called PUFAs). For optimal brain function, omega 3 fatty acids are increased in the diet of children and adults. Did you notice recently that DHA has been added to baby food to increase more omega 3 fatty acids even in the diets of infants of a specific age who are eating their first solid foods?
You don't want to end up with various oils competing with one another for certain enzymes. One type of oil can inhibit the conversion of enzymes. The problem is with the standard Western diet that contains too many dietary plant oils rich in omega 6 PUFAs, such as corn, safflower, and soybean oils.
Again, balance is needed rather than excess of any one food. But with all the food you eat in restaurants or fast food eateries and sometimes at home fried in vegetable oils with too high an omega 6 fatty acid content, that's when the imbalance may happen.
What you need to do is check out the article, "Workshop on the Essentiality of and Recommended Dietary Intakes for Omega-6 and Omega-3 Fatty Acids," published in Journal of the American College of Nutrition, Vol. 18, No. 5, 487-489 (1999). More recently, in a BMJ article entitled Adherence to Mediterranean diet and risk of developing diabetes: prospective cohort study the authors wrote in the Conclusion, "Our prospective cohort study suggests that substantial protection against diabetes can be obtained with the traditional Mediterranean diet, rich in olive oil, vegetables, fruits, nuts, cereals, legumes, and fish but relatively low in meat and dairy products."
Under the heading Diet and Disease the authors wrote, "Apart from olive oil, adherence to an overall Mediterranean-type food pattern is related to lower plasma concentrations of inflammatory markers and markers of endothelial dysfunction." So, that may be part of the answer to why olive oil is helpful.
The Mediterranean diet does seem to reduce inflammatory markers for some people
To explain why, in a paper, "Dietary Fat Quality and Coronary Heart Disease Prevention: A Unified Theory Based on Evolutionary, Historical, Global, and Modern Perspectives," the authors note that "The only long-term trial that reduced n-6 LA intake to resemble a traditional Mediterranean diet (but still higher than preindustrial LA intake) reduced CHD events and mortality by 70%. Although this does not prove that LA intake has adverse consequences, it clearly indicates that high LA intake is not necessary for profound CHD risk reduction." Each person based on metabolic and genetic reasons may respond differently to any given diet.
So folks, thanks to a reader from the Nutrition Education Project, who sent me this material, here utilized, with written permission, you also need to investigate the excess omega-6 hazard. Did you ever notice that it is now a century since omega 6 seed oils have been introduced into the Western world's food supply? What were folks using for cooking oil one hundred years ago? The answer is whatever oils or fats were used in anyone's specific ethnic group in the previous century.
Check out the 1895 cookbooks--lots of cream, butter, and/or coconut oil
On the other hand, you don't want an excess of dairy either. Some people can't tolerate dairy products. With homogenization, the tiny molecules aren't what you want to load up on. This was not so great 100 years ago for the lactose-intolerant or for those who had adverse reactions to any type of dairy products when bread was buttered instead of dipped in warmed olive oil and garlic as they did along the Adriatic and in some Mediterranean areas. Are you getting enough omega 3 fatty acids in this century as you balance your diet?
Would you rather dip your food into unheated extra virgin olive oil, organic butter from grass-fed animals, rendered chicken fat, coconut oil, bacon fat, or lemon and/or lime juice? A century ago, for example, rendered chicken fat, butter, and cream, were commonly used among Central Europeans, lard among many different peoples in the new World and in many areas of Europe, beef suet/fat among others, coconut oil among people from more tropical areas, and olive oil in Mediterranean regions.
South Asians used sesame oil or clarified butter (ghee). The worse time for shortening in the USA ran from the 1920s to the 1950s when trans fats were sold in cans as solid white shortening. And people started frying potatoes, meats, and fish in transfats, those partially hydrogenated fats. What should you do today? Get enough omega 3 fatty acids and remember, everything in balance.