Fishy Findings: Omega-3 Supplement Research Remains Inconclusive
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If you've been following the media trail on fish oil lately, you've probably been tempted to forgo the smelly capsules. A systematic review of 20 studies published last week in JAMA The Journal of the American Medical Association reported that neither eating extra helpings of fish nor taking fish oil supplements reduces the risk of stroke, heart attack or death. In June a review of studies published on behalf of the Cochrane Collaboration, an independent, not-for-profit organization that promotes evidence-based decision-making, concluded that fish oil pills fail to prevent or treat cognitive decline. And a 2011 meta-analysis by Yale University researchers debunked the idea that omega-3s alleviate depression. These proclamations run counter to what we have been told about fish and fish oil for decades. So why is the consensus changing? Is it time for us to toss out our pills for good?
Not necessarily. Although it's true that early research on fish oil seemed far more promising—one 1999 trial, for instance, reported that people who took omega-3 pills were 10 percent less likely to have a heart attack, stroke or die from cardiac disease than people who did not—some researchers think that recent negative findings reveal more about us than they do about fish oil. Omega-3 pills may be beneficial for certain people but not for others, they say, and existing studies may not account for individual differences.
There's no question that polyunsaturated omega-3 fatty acids—the technical name for the good fats found in fish and fish oil—are important parts of a healthy diet. Our bodies can't make them, yet we need them to survive, as they form part of our cell membranes. Although the mechanism by which they might prevent heart disease, cognitive decline and depression isn't well understood, research suggests that they reduce blood pressure and inflammation and that they increase brain blood flow and give neurons structural strength.
And no one questions the World Health Organization's recommendation (pdf) that pregnant and nursing women should consume at least 300 milligrams of omega-3s daily to boost fetal brain development. "That [benefit] has been clearly demonstrated in trials," says Dariush Mozaffarian, a cardiologist and epidemiologist at Harvard University, who studies fish oil.
But for other adults, the health benefits of supplementing have become much harder to gauge. That's in part because many of us get lots of these good fats from our diet anyway: According to the United Nations Food and Agriculture Organization, per capita fish consumption has doubled (pdf) since 1961, and "more consumption doesn't really add much bang for your buck," Mozaffarian says. In other words, adding more omega-3s to an already omega-3–rich diet does not do much good, a fact that could help explain why recent studies have been more equivocal than studies from several decades ago, when fish was less popular. "We have no evidence from populations whose dietary intake of omega-3 fatty acids may be low and who may therefore benefit from supplementation," says Alan Dangour, head of the nutrition group at the London School of Hygiene and Tropical Medicine and co-author of the recent Cochrane review. In addition, preliminary research suggests that certain ethnic groups—such as Japanese and Italians—may benefit more from omega-3 supplements than others, perhaps in part because of how well their bodies absorb the fats.
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21 Comments
Add CommentI have anecdotal testimony...
Reply | Report Abuse | Link to thisAfter many months of (my second round of) chemo administered by my gastrointerologist, including Interferon injections producing severe anemia, my cardiologist independently prescribed Lovaza to treat high triglycerides.
Knowing nothing about omega-3s, after a week or two my cognitive abilities had been remarkably improved, restored (not knowing they had diminished) to levels I hadn't known for years. Continued use hasn't prevented progressive development of aortic valve stenosis (calcification), but I apparently haven't yet suffered any noticeable dementia...
Based on my investigations of the remarkable effects I experienced (not knowing what could have possibly been responsible for any improvement in cognitive abilities), I suspect that the (prescription quality) omega-3 supplements had enabled repair of insulated fatty myelin sheaths of neuronal axons previously damaged from severe anemia. For this reason I suggest that anyone suffering from anemia, particularly those undergoing anemia producing chemo therapy, supplement their diet with (at least 1 Gm daily) omega-3.
I do suggest that medical evaluations of the cognitive abilities of those who have suffered effects of anemia be undertaken. Since my results were very remarkable within 2 weeks, I expect that significant results can be obtained very quickly.
I was a pack a day smoker for 30 years and I began taking salmon oil in the 90s. I have continued to the present day. I quit smoking in 2008 and I am happy to say that thanks to the fish oil, I have no smokers cough.
Reply | Report Abuse | Link to thisI think that the real benefit to any omega 3 oil is in helping the aging body to maintain moisture in key areas. The lungs, the heart, the eyes especially seem better for me due to taking it. Does the study look at that aspect? I did not see anything about it in your article.
Purslane is a weed you can pick from your backyard, and has more omega-3 fatty acids than fish oil. All you're doing by buying these 'vitamins' is enriching pharma, the ones trying to eradicate nutritious weeds like dandelions. Foraging: the lost knowledge of an entire generation.
Reply | Report Abuse | Link to thisThanks to fish oil you don't have smokers cough? Seriously? When you stop smoking, the cilia in your trachea regrows, helping to push out foreign matter. Correlation != Causation ... those moisture health-and-beauty claims are also suspect.
Reply | Report Abuse | Link to thisI've never understand these dumb, largely short-term studies. The THEORY dating back to the 1990s is that the RATIO of Omega-3 to Omega-6 is the key feature. Modern western diets derived literally 40+% of their calories from grain and grain-fed animals and have a bad 3/6 ratio (according to the theory). The fatty acids are key to the building of brain and other body structures which are recycled very slowly once built. Since the body uses Omega-6 if it doesn't have enough Omega-3, the structures still get built - just not as good (allegedly). It would obviously take YEARS of supplementation to reverse/rebuild the affected structures - if EVER. So giving a middle-aged man like myself extra omega-3 might help (Disclaimer: I've always loved and eaten fish AND take a Omega-3 supplement) - I think it is more critical for pregnant women (for the fetus) and children. STUDY THAT PLEASE.
Reply | Report Abuse | Link to thisTruly I have no cough. I suppose my lungs are emptying out - I clear my throat now and then - but I have no cough. I tried stopping fish oil and eating a bit more olive oil, I still did not cough, but I lost the capability to wear my contact lenses. Could not keep my eyes moist enough. Floaters increased too. I began taking fish again and the dryness and excessive floaters went away. I am not a doctor or a scientist I can only tell you what my experience has been.
Reply | Report Abuse | Link to this"some researchers think that recent negative findings reveal more about us than they do about fish oil."
Reply | Report Abuse | Link to thisVery likely - e.g. that people who take fish oil pills or similar, in general live a more healthy life than the average person. This would easily account for seamingly positive results from fish oil.
greenshadow22
Reply | Report Abuse | Link to this"thanks to the fish oil, I have no smokers cough."
Ahrm, when you stop smoking it is common to have a "smoker's cough" for 3 to 6 months. When your lungs have regenerated some it stops, whether you take fish oil, Jelly-O or liquorice.
What does alleviate depression is increasing your intake of Vitamin D especially during times of the year when your shadow at noon is longer than your height.
Reply | Report Abuse | Link to thisIt is during this time that the UVB rays (that produces vitamin D in the skin) are increasingly blocked by the ozone layer in the upper atmosphere.
Another fish story, eh?
Reply | Report Abuse | Link to thisjtdwyer:Re:possible reversal of aortic valve stenosis by diet,
Reply | Report Abuse | Link to thisI would recommend to you the excellent cardiovascular diet concept of Dean Ornish M.D. from Harvard University ( vide under Google).
As to omega-3 accessibility other than through supplements: Consider to add natural flaxseed , which has the highest omega3 content of any plant food, and can be easily added to breakfast cereals like oats ; just add water to a spoonful, and soak overnight. An easy omega- 3 'designer' muesli recipe is on my website: youthevity.com
For information about fish oils that has not been biased by industry or big pharma buying the results they want, you should visit the website of the Weston A. Price Foundation.
Reply | Report Abuse | Link to thisOmega 3 benefits have been widely discussed around the world where in it was believed that it can greatly help in the body system. Fish oil is enriched with omega 3 fatty acids that can help in making the body healthier. However, there are always controversies on this matter because of different researches coming out around the world.
Reply | Report Abuse | Link to thisWith over 12,000 clinical studies conducted on fish oil, it is interesting that the verdict is still out.
Reply | Report Abuse | Link to thisI would be very surprised if not pharma paid for this meta analysis. The last two in in 2007 and 2010 was indeed paid for by pharma. Why? They want to sell more drugs.
Note: meta analysis is not a study, it is just a review of studies based on what the "investigators" decide, on their own, to be the threshold of significance.
I have taken fish oil for 20 yrs. My triglycerides are 55, my LDL cholesterol is 130, my HDL cholesterol is 73. I don't eat fish. The doctor tells me I am at zero risk for a heart attack. Go figure.
Or... go fish oil, and screw the disturbing "meta analysis" which pops up every two yrs.
Search at
http://www.ncbi.nlm.nih.gov/sites/entrez
and see how many hits you get about the benefits of taking fish oil - from the premier research database in the world - used by all leading universities and research orgs.
Take fish oil, not drugs.
Thanks Vapur for reminding me about purslane. Another good source for vegetarians is flax seed. I grind two tablespoons fresh every morning, in a little coffee grinder, and mix into my oatmeal--since I believe much of the benefit of any food dissipates fairly quickly when processed (and to the extent of the processing). Therefore, fresh-ground instead of purchased as an oil, capsule, etc.
Reply | Report Abuse | Link to thisMy lungs didn't get the news I guess. I really did not have a cough.
Reply | Report Abuse | Link to thisJust sounds a bit fishy to me!
Reply | Report Abuse | Link to thisBut realistically why not just eat a piece of fish once a week and save money, and stop the pharma companies from making all the money.
My story: my hair was falling out by the hand full. I started taking fish oil (4-5,000 mg a day) now for 5+years. Have had a wonderful full head of hair for years & I have been sick maybe 2x?. I am sold that fish oil is very good for you.
Reply | Report Abuse | Link to thisIt is best to keep the omega 3 vs omega 6 ratio under 1:5. 1:1 would be ideally, but this is really hard to achieve. Take a look at this article on <a href="http://healthiack.com/health/omega-3-vs-omega-6-ratio">omega 3 vs 6 ratio</a>. The best way to equalize this ratio is to eat less omega 6 foods, and more omega 3s foods. For most of people this means eating less fat foods and start to consume more <a href="http://healthiack.com/health/omega-3-foods">omega 3 rich foods</a>. Fish are a great source of omega 3 by the way.
Reply | Report Abuse | Link to thisregards, Tej
It is best to keep the omega 3 vs omega 6 ratio under 1:5. 1:1 would be ideally, but this is really hard to achieve. Take a look at this article on <a href="http://healthiack.com/health/omega-3-vs-omega-6-ratio">omega 3 vs 6 ratio</a>. The best way to equalize this ratio is to eat less omega 6 foods, and more omega 3s foods. For most of people this means eating less fat foods and start to consume more <a href="http://healthiack.com/health/omega-3-foods">omega 3 rich foods</a>. Fish are a great source of omega 3 by the way.
Reply | Report Abuse | Link to thisregards, Tej
It is best to keep the omega 3 vs omega 6 ratio under 1:5. 1:1 would be ideally, but this is really hard to achieve. The best way to equalize this ratio is to eat less omega 6 foods, and more omega 3s foods. For most of people this means eating less fat foods and start to consume more omega 3 rich foods.
Reply | Report Abuse | Link to thishttp://heathiack.com/health/omega-3-foods.
Fish are a great source of omega 3 by the way.
regards, Tej