I’ve written before about the dangers of omega-6 PUFAs in the diet, and how high intake of PUFAs in the Western diet may be a culprit in the significant increase in inflammatory diseases, including cardiovascular disease, type 2 diabetes, obesity, cancer, autoimmune disease, and more. (1, 2) We’ve known for a while now that a correlation exists between a rising intake of n-6 and increased mortality from heart disease. (3)
You may have already changed your diet back to one containing high saturated fat from butter, meat, and coconut products, much to the dismay of your doctor and perhaps even your skeptical family members. The belief that omega-6 rich vegetable oils are the “heart healthy” choice is pervasive, despite limited and controversial evidence. It can be difficult to convince others that you’re not asking for a heart attack by eating saturated fat.
Now, thanks to research published last week in BMJ, an old study is shedding new light on the omega-6 fatty acids and heart health controversy. The Sydney Diet Heart Study was a randomized controlled trial conducted from 1966 to 1973, comprising 458 men aged 30-59 years with a recent coronary event, such as a heart attack. Patients were randomized to either a control diet (e.g. no change) or an intervention diet, where they were instructed to increase their omega-6 PUFA intake to 15% of calories and to reduce saturated fat intake to less than 10% calories. Participants were provided with liquid safflower oil and a safflower oil based margarine to be used instead of animal fats. (They were also given safflower oil in capsules to take as a supplement. Yikes!)
As expected, those in the treatment group had a significant lowering of total and LDL cholesterol concentrations, which the original investigators assumed would therefore lead to the prevention of cardiovascular death. However, when accounting for previously lost data, this new analysis found that the intervention group instructed to eat more linoleic acid (n-6 PUFAs) actually had a higher risk of all cause mortality, as well as a higher risk of mortality from cardiovascular disease and coronary heart disease, than the group who received no dietary instructions.
Furthermore, an updated meta-analysis of linoleic acid intervention trials included in the paper showed no evidence of cardiovascular benefit. In other words, replacing saturated fat with high omega-6 vegetable oils is likely to put you at a greater risk for heart attack, and it certainly won’t provide any health benefits. It’s important to note that previous analyses that suggested increasing PUFA intake reduces the risk of CVD included both omega-6 and omega-3 PUFA together; the analysis in this study analyzed the effects of omega-6 linoleic acid separately.
Could “heart healthy” vegetable oils be putting you at risk for a heart attack?
So why are Americans still eating diets that are so high in omega-6 vegetable oils, with almost 9% of all calories from linoleic acid alone? (PDF) Despite the many studies that show the dangers of a high omega-6 PUFA intake, the conventional medical system is still preaching outdated and inaccurate information. The American Heart Association (AHA) recommends that we all aim for at least 5 percent to 10 percent of calories from omega-6 polyunsaturated fatty acids (PUFAs), and to limit saturated fat intake to less than 7 percent of total daily calories, similar to the recommendations made in the Sydney Heart Diet study. (4)
They suggest we choose “heart healthy” oils and margarines such as canola, corn, olive, peanut, safflower, sesame, soybean, and sunflower oils. This information is coming from the professional organization whose stated mission is “to build healthier lives, free of cardiovascular diseases and stroke.” But as we know by now, these guidelines are not going to protect anybody from a heart attack, and could likely put people at a greater risk for cardiovascular disease. (5)
As more evidence surfaces about the dangers of high omega-6 PUFA consumption, it will be more difficult to defend the current AHA guidelines for fat consumption that are currently promoted by conventional health professionals. It seems the tide may be turning (slowly) when it comes to dietary fat recommendations, but it will be interesting to see how the American Heart Association responds to this new study. While we wait for the policy makers and medical organizations to battle it out, I’ll stick to eating butter!
To read more about heart disease and cholesterol, check out the special report page.
Better supplementation. Fewer supplements.
Close the nutrient gap to feel and perform your best.
A daily stack of supplements designed to meet your most critical needs.
I’m mostly on board with the anti-PUFA sentiment especially due to solvent use in industrial seed oils, but I don’t think that this study supports the theory that well due to an additional variable: Couldn’t the hydrogenated oil (margarine) content also account for the increased all cause mortality?
Hi Chris,
Firstly, thank you so much for all of your hard work and having all of this wonderful information here for the public and for free. I’m always really disappointed in people who take a totally disrespectful tone in their comments. It seems to me that even if one disagrees with what you’re saying, there’s just no need to be disrespectful (yes, I’ve been reading over the pet post on PUFAs!).
And- do you know if there has been any comment by the AHA on the recently published ‘rediscovered’ Sydney Diet Heart Study?
I recently tried to explain this saturated fat concept and omega 3:6 to my brother and he just kept saying that if the government teaches it in schools then it must be correct (and I’m wrong).. It was frustrating for me obviously but I can see where he’s coming from. These government bodies really need to be more up to date on their recommendations and stop trying to save face quite so much!
Cheers- Sonia (Byron Bay- Australia) 🙂
AHA already responded “we see your study and still don’t care, we have to keep receiving money from the veggie oil industry and all those fake buttery spreads”
Hi Chris,
Thank you for the article. I have a few quibbles.
The increased risk associated with omega-6 group was not statistically significant. So isn’t it a bit of a stretch to say it “likely” will increase your risk of a heart attack, when the results are explainable by chance variation?
Also, the omega-3 intake of the control group (i.e. the saturated fat group) was unaccounted for. If the omega-6 group replaced animal foods by vegetable oils, there is conceivably a decrease in omega-3. This might at least partly explain any increased CVD risk seen in the omega-6 group.
Sorry, I misread. The original recovered data did reach statistical significance. It was the updated meta-analysis that still wasn’t statistically significant (though it was borderline: P=0.06 for CHD, and P=0.07 for CVD).
Thanks for this. I am currently attending the 11h annual Cardiovascular Disease Prevention International Symposium in Miami and this article that I was unaware of seems hot off the presses. I am curious to see if the speaker on Sunday that will be speaking about Omega fatty Acids and disease will acknowledge this article. Thanks Again.
David, the usual theme is that omega-6 MUST be good for us because it lowers cholesterol therefore risk. Measuring mortality rather than markers (all that was measured in the studies you linked) gives a different verdict.
The reality rather than the theory of cardiovascular disease.
I’ve recently increased saturated fats intake (like butter) to keep cholesterol high enough and healthy levels, and use it as the main source of energy replacing carbs. But I thought extra-virgin olive oil is a healthy choice as well if consumed raw. The article seems to imply it is not when it puts it together with other seeds oil. I think it is different due to its high monoinsaturated fats content.
If the omega 6 oils are bad for us, I wonder how these studies http://www.ncbi.nlm.nih.gov/pubmed/22889633 can claim that they are perfectly healthy?
I always thought that butter was the way to go and it taste’s better to boot. Thanks Chris!!
Chris, I’d like to know your thoughts on the idea that dairy fat can cause hypercholesterolemic effects in certain people, as described here: http://paleohacks.com/questions/36855/i-think-i-may-have-figured-out-why-some-of-us-have-really-high-ldl#axzz2Kyv9z4yC
Initial response from American Heart Assoc:
American Heart Association spokesperson Penny Kris-Etherton, a registered dietician and professor of nutrition at Pennsylvania State University, suggested that the controversy concerning linoleic acid is not new and will continue.
“But I don’t think this is going to change AHA recommendations,” she said. “Because there’s very robust evidence showing the cardiovascular benefit of linoleic acid. The AHA science advisory board did not just look at one study or a couple of studies. There are lots of studies that form the basis for their guidelines.”
“So, I don’t think anybody should get alarmed and change their diet,” Kris-Etherton said. “Those who are concerned should wait for more research to come out on this topic before taking any drastic measures to change their eating habits in a way that could be harmful.”
I hate to say it, but I do think more research probably needs to be done.
I agree, we probably still need more research. However, I’d say similar advice to what they just gave was warranted when they FIRST made recommendations to increase consumption of linoleic acid. Perhaps then people wouldn’t have been so quick to switch from fresh butter that they could produce in their backyard, to margarine or soy oil which have to come highly processed from a factory.
Alyssa, good point didn’t even think of that
I eat a lot of butter, but I eat a lot of olive oil, too. Perhaps too much olive oil. I avoid all of those other oils entirely, except for a teaspoon of sesame oil now and then to flavor certain dishes. It’s easy to avoid most of them if you avoid packaged food.
Today I saw this study came out http://www.nutritionandmetabolism.com/content/10/1/23/abstract .”n-3 PUFA added to high-fat diets affect differently adiposity and inflammation when carried by phospholipids or triacylglycerols in mice” (yes, I realise its in mice)
http://newsroom.heart.org/news/no-change-in-aha-recommendations-on-saturated-or-poly-unsaturated-fat
A slightly better response from the British Heart Foundation:
http://www.bhf.org.uk/default.aspx?page=15680
With any luck they’ll come round to the idea. I’m curious where the French stand on this.
I find this a bit sad given that some individuals might have had a reduced lifespan due to some of these recommendations
Heading should be grass fed butter or cool season grass fattened beef, similar to cold water fish. All naturally concentrated plant carotenoids and antioxidants for optimum health.
Could you expand on your recommendation for cool season grass fattened beef? We know that butter and other dairy foods are best during the spring and fall months when grass is green and rapidly growing. I’ve often thought about meat in the same way, wondering what the ideal times are. Would the cool periods for beef mean that the animal is harvested in fall? For pork, I assume the highest nutrient content (in particular, vit D, which they metabolize from the sun as we do) would be late summer.
“safflower oil based margarine”
Margarines are typically created by hydrogenation of liquid vegetable oils which produces trans-fat. Trans fats are condemned by those that advocate Omega 6 polyunsaturated and monounsaturated oil over saturated fat consumption. Similarly, the advocates of “natural” saturated fats steer their adherents away from trans fat, so…
Unless I know whether and how much of the Omega 6 oil was in solid form, this study may not make butter as wise a choice as it seems. Surely you’re better off with butter or lard than margarine or shortening, so the one does not preclude the other.
Important additional data can be found from 2009: “Add Omega 3’s, but No Need to Limit Omega 6’s”
http://www.drmirkin.com/public/ezine020109.html
Which oils are the most help to lower PUFA’s?
http://integrativemed.kumc.edu/school-of-medicine/integrative-medicine/health-topics/healthy-cooking-oils.html
For more Omega 6 news:
http://www.drmirkin.com/morehealth/8875.html
http://www.drmirkin.com/nutrition/9483.html
http://www.drmirkin.com/public/ezine052508.html
Omega 3’s
http://www.drmirkin.com/nutrition/1708.html
Taking in more Omega 3’s without decreasing Omega 6’s can be bad news.
http://www.ncbi.nlm.nih.gov/pubmed/23298440
Wow, that’s an interesting study J.W. I suppose that taking a Krill oil supplement would help manage the oxidative stress. Also consuming herbs and spices that are anti-inflammotory would help under these circumstances as well. Encouraging an “oil change” is in order. Thanks for sharing.
And don’t forget that omega-3 fatty acids are also unsaturated, just like omega-6. This makes BOTH of these essential fatty acids delicate to processing and likely to go rancid (both during extraction and within the human body if they hang around too long). This is why BOTH omega-3 and omega-6 fatty acids should be eaten sparingly (and in a near-perfect balance). They should also come from food or high-quality supplements (but food is the preferred source).
I wouldn’t “boil” the butter when making ghee, just gently simmer it until the moisture is removed and then filter it. Ghee is high in butyric acid which is very good for the colon.
Is there any health difference of butter vs. ghee?
Ghee is clarified butter with almost zero lactose. So if you have digestive issues with butter, ghee is an excellent alternative.
Ayurvedic medicine favors ghee over butter. See http://books.google.com/books?id=fOK33vv_29UC&pg=PA52&dq=ghee&hl=en&sa=X&ei=OMseUdLADe30iwKLiYGwDA&ved=0CGYQ6AEwBw#v=onepage&q=ghee&f=true and http://books.google.com/books?id=v4Hat6niCzoC&pg=PA85&dq=ghee+ayurveda&hl=en&sa=X&ei=x8weUd_KDuLIigKitoGgBw&ved=0CEQQ6AEwAjgo#v=onepage&q=ghee%20ayurveda&f=true
Ghee is considered more balanced for many Ayurvedic constitutional types than butter.
For those who handle butter fine and don’t perform very well on an overwhelmingly raw food diet, I would use both as they have different properties.
Because ghee has the milk solids removed it can be heated to a much higher temperature. So ghee is great for cooking. It’s very easy to make ghee, you basically just boil butter until all the milk solids rise to the top and then you filter them out with cheese cloth. Make sure you use a good quality pasture butter to get the Omega 3 benefit.
Agreed Chris! It’s time to put the fear of saturated fat to rest.
I melt a blend of butter ghee and coconut oil together, and much like Frank’s Redhot Sauce, I put that “$#*!” on everything!
I wonder why this study wasn’t news when it came out in the 70s. Why is it only resurfacing now? It’s certainly not a new study. It’s infuriating that studies had shown this correlation thirty plus years ago and doctors and agribusiness and nutritionists are still touting “heart healthy vegetable oils”.
Of course, this study showed a lowering of total and LDL cholesterol, and that paradigm that cholesterol causes heart disease (which is false as we know) trumped whatever other findings there were.
Margaret, I think that polyunsaturated fats (and other supposedly “heart healthy’ foods) are slowly losing their perception as being healthy by researchers. This loss of faith might help encourage more researchers to challenge the current nutritional dogma, possibly resulting in some legitimate nutritional advice. Unfortunately, as hard as it is to change people’s minds, this might take another decade or two to actually happen. 🙁
I’ve switched to more saturated fat, especially coconut oil and butter and trying hard to cut way back on the industrial seed oils. Now I just read in the latest edition of Life Extension magazine that a study in the European Journal of Clinical Nutrition showed that men experienced a decrease in average telomere length in association with a greater intake of fat, particularly butter. The men who restricted fat and ate more fruit had longer telomeres. Of course, it didn’t say how much omega-6 fat the men were eating.
Why does nutrition have to be so complicated? How about more butter and fruit?