Another potential problem is that most of the research on fish oil and heart health—including all of the trials included in the recent JAMA analysis—have involved subjects who already have heart disease or established risk factors. Whereas this isn't necessarily a problem in itself, it means that very little research has addressed whether fish oil supplements benefit healthy people. "The jury is still out on whether omega-3 supplements can prevent a first cardiovascular event in people at usual risk," says JoAnn Manson, an epidemiologist at Brigham and Women's Hospital in Boston who is conducting a trial to answer this question, which she estimates will be finished in 2016.
Moreover, because so many trials have involved subjects with heart problems, subjects in recent years have been "taking multiple medications, such as aspirin and statins, which can obscure the effects of supplements," Manson says. (Half of the studies included in the JAMA analysis were conducted after statins became commonplace.) This fact could also help explain the outcome discrepancies between recent trials and older ones carried out during the pre-statin era. Indeed, a February 2012 analysis of a large European clinical trial reported that fish oil supplements do not prevent second heart attacks among people taking statins, but that it cuts risk by half among people who don't take the medications. (Because there were so few non-statin users enrolled in the trial, this finding did not quite reach statistical significance.)
People who enroll in and complete omega-3 trials may differ from typical Americans in important ways, too. "Members of the public who volunteer to join randomized controlled studies are frequently healthier and more active than the average for the population," Dangour says, which could affect outcomes in unknown ways. In addition, he adds, people who drop out of trials are often the sickest, and they might be the ones who would most benefit from supplementation.
There's also more than one type of fish oil. Typically, in omega-3 intervention studies, subjects take pills containing a near-equal mixture of two fats, docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA)—but some research suggests that in certain situations and for certain outcomes, one may be better than the other. For instance, a 2011 meta-analysis concluded that fish oil capsules don't help treat depression, but a group of British and Norwegian researchers challenged these findings, citing evidence that pills containing at least 60 percent EPA do seem to provide mood benefits. Another controversial question is whether the omega-3 dose is important in and of itself or whether the ratio of omega-3 to omega-6 fats one consumes is more important. (Although omega-6 fats are important for survival, Americans tend to consume far more of these fats than they need.)
Finally, whereas the recent JAMA analysis concluded that fish oil has no effect on cardiovascular outcomes, the researchers did find that omega-3s reduced the risk of cardiac death by 10 percent, an effect that was statistically significant (having a "p value" of 0.01). The researchers did not report the finding in their conclusions because they subsequently modified their statistical calculations to account for the fact that they had used the same data set to ask a number of different "exploratory" questions: In this case, does fish oil prevent heart attacks? Strokes? What about sudden cardiac death? The team wanted to tighten their definition of statistical significance to account for the fact that the more questions one asks, the more likely one is to get a positive result by chance. Still, Mozaffarian says, "if you combine all the data and look only at cardiac death, there is a statistically significant benefit. A 10 percent reduction in the number-one cause of death in both men and women in the U.S. is a big deal."
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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