Beware Of More Misinformation From The American Heart Association On Coconut Oil and Saturated Fats

In a “presidential advisory” to the American Heart Association (AHA)  a panel of experts last week  strongly endorsed the heart healthy benefits of replacing any and all saturated fats in our diet with vegetable oils (like corn , soy, and canola oil) which contain predominantly poly  or mono unsaturated fats.

Examining the metrics of this article it appears that the vast majority of news media reporting on it have lead with a headline that reads:

  Coconut oil isn’t actually good for you, the American Heart Association says     

Given this brazen attempt by the AHA to smear coconut oil’s reputation I felt compelled to revisit my analysis of coconut oil from a year ago. I’ve included new discussion on a key paper referenced by the AHA advisory and some words of wisdom from Gary Taubes.

Coconut Oil: Poster Child for Dietary Fat Confusion

Coconut oil (CO) is a microcosm of the dietary confusion present in the U.S. On one hand a CO Google search yields a plethora of glowing testimonials to diverse benefits: Wellness Mama lists “101 Uses for Coconut Oil,” Authority Nutrition lists “10 Proven Health Benefits.”

On the other hand, the  American Heart Association (AHA) and the USDA’s Dietary Guidelines For Americans warn us to avoid consuming coconut oil  because it contains about 90% saturated fat (SFA) which is a higher percentage than butter (about 64% saturated fat), beef fat (40%), or even lard (also 40%)

In many respects, the vilification of coconut oil by federal dietary guidelines and the AHA resembles the inappropriate attack on dairy fat and is emblematic of the whole misguided war on dietary fat. In fact, the new AHA advisory  after singling out coconut oil goes on to cherry-pick the data on dairy fat and cardiovascular disease in order to  support their faulty recommendations for choosing low or nonfat dairy..

The AHAs simple message to replace all saturated fats in your diet with poly unsaturated fats (PUFAs) or monounsaturated fats (MUFAs) is flawed because:

  1. All saturated fats are not created equal :the kinds of saturated fats in coconut oil differs markedly from both dairy SFAs and beef SFAs . Some  SFAs may have beneficial effects on blood lipids, weight, and cardiovascular health.

  2. The types of nonSFAs in vegetable oils differ markedly and may have differential effects on cardiovascular health.

All Saturated Fats Are Not Created Equal!

Saturated fats are divided into various types based on the number of carbon atoms in the molecule. Depending on length, they differ markedly in their metabolism, absorption and effects on lipid profiles.

The major SFA in coconut oil, lauric acid, has a 12 carbon chain and is thus considered a medium chain fatty acid (MCFA).

The AHA advisory makes a cursory attempt to address the huge hole in their logic primarily relying on a meta-regression analysis published in 2003 by Mensink, et al., and concludes:

The Mensink meta-regression analysis determined the effects on blood lipids of replacing carbohydrates with the individual saturated fatty acids that are in common foods, including lauric, myristic, palmitic, and stearic ac- ids. Lauric, myristic, and palmitic acids all had similar effects in increasing LDL cholesterol and HDL cholesterol and decreasing triglycerides when replacing carbohydrates

In summary, the common individual saturated fats raise LDL cholesterol. Their replacement with monounsaturated or polyunsaturated fats lowers LDL cholesterol. Differences in the effects of the individual fatty acids are small and should not affect dietary recommendations to lower saturated fat intake.

But if we examine what the actual paper by Mensink et al (available in full here) we find their conclusions are the exact opposite of the AHA:

Lauric acid greatly increased total cholesterol, but much of its effect was on HDL cholesterol. Consequently, oils rich in lauric acid decreased the ratio of total to HDL cholesterol. Myristic and palmitic acids had little effect on the ratio, and stearic acid reduced the ratio slightly.

The differences in the effects of the individual fatty acids are not small they are quite significant if we look at the totality of the effects on lipids relevant to cardiovascular disease. In their discussion, Mensink, et al go on to say:

Our results emphasize the risk of relying on cholesterol alone as a marker of CAD risk. Replacement of carbohydrates with tropical oils markedly raises total cholesterol, which is unfavorable, but the picture changes if effects on HDL and apo B are taken into account.

What’s more :

The picture may change again once we know how to interpret the effects of diet on postprandial lipemia, thrombogenic factors, and other, newer markers. However, as long as information directly linking the consumption of certain fats and oils with CAD is lacking, we can never be sure what such fats and oils do to CAD risk.

This graph from Mensink, et al. shows what would happen to the total/HDL cholesterol ratio if we substituted various foods in place of 10% mixed fat. Theoretically a lower ratio is more heart healthy. Look at the drastic differences between palm oil, coconut oil and butter, all of which are condemned by the AHA

 

Misguided Dietary Fat Recommendations

The  AHA experts have doubled down on their recommendation to use cooking oils that have less saturated fat such as canola and corn oil. They advise, in general, to “choose oils with less than 4 grams of saturated fat per tablespoon.”

Screen Shot 2016-05-07 at 12.28.40 PMCanola and corn oil, the products of extensive factory processing techniques, contain mostly mono or polyunsaturated fats which have been deemed “heart-healthy” on the flimsiest of evidence.

The most recent data we have on replacing saturated fat in the diet with polyunsaturated fat comes from the Minnesota Coronary Experiment performed from 1968 to 1973, but published in 2016 in the BMJ.

Data from this study, which substituted liquid corn oil in place of the usual hospital cooking fats, and corn oil margarine in place of butter and added corn oil to numerous food items, showed no overall benefit in reducing mortality. In fact, individuals over age 65 were more likely to die from cardiovascular disease if they got the corn oil diet.

Cherry-Picking Data

The new AHA presidential advisory doesn’t include this study or  data from the Sydney Heart Study, another study with negative results for substituting PUFAs for SFAs.

As Gary Taubes pointed out in a post for Larry Husten’s cardiobrief.org blog, the AHA experts cherry-picked four “core trials” that  agreed with their hypothesis and excluded the ones that don’t agree:

They do this for every trial but the four, including among the rejections the largest trials ever done: the Minnesota Coronary Survey, the Sydney Heart Study, and, most notably, the Women’s Health Initiative, which was the single largest and most expensive clinical trial ever done. All of these resulted in evidence that refuted the hypothesis. All are rejected from the analysis. And the AHA experts have good reasons for all of these decisions, but when other organizations – most notably the Cochrane Collaboration – did this exercise correctly, deciding on a strict methodology in advance that would determine which studies to use and which not, without knowing the results, these trials were typically included.

Coconut Oil: The Bottom Line

After all is said and done, it would appear that coconut oil, despite coming from a vegetable, resembles dairy fat in many ways.

It is more likely than not that coconut oil, like dairy fat, reduces your chances of obesity and heart disease, especially when compared to the typical American diet of highly processed and high carbohydrate foods.

Although containing lots of saturated fat, the SFAs in coconut oil are drastically different from other dietary sources of SFA.  The medium chain fatty acids like lauric acid which make up the coconut are absorbed and metabolized differently from long chain fatty acids found in animal fat.

The only explanation for dietary guidelines advising against coconut oil and dairy fat is the need to stay “on message” and simplify food choices for consumers, thus continuing the vilification of all saturated fats.

Substituting corn oil (or other vegetable oils with lots of linoleic acid) for foods containing saturated fats does not lower risk of heart disease and may promote atherosclerotic outcomes like heart attack and stroke.

Finally, I agree with Taubes that we deserve good scientific studies proving without a doubt that these drastic changes in diet are truly helping:

“telling people to eat something new to the environment — an unnatural factor, à la virtually any vegetable oil (other than olive oil if your ancestor happen to come from the Mediterranean or mid-East), …..is an entirely different proposition. Now you’re assuming that this unnatural factor is protective, just like we assume a drug can be protective say by lowering our blood pressure or cholesterol. And so the situation is little different than it would be if these AHA authorities were concluding that we should all take statins prophylactically or beta blockers. The point is that no one would ever accept such a proposal for a drug without large-scale clinical trials demonstrating that the benefits far outweigh the risks. So even if the AHA hypothesis is as reasonable and compelling as the AHA authors clearly believe it is, it has to be tested. They are literally saying (not figuratively, literally) that vegetable oils — soy, canola, etc — are as beneficial as statins and so we should all consume them. Maybe so, but before we do (or at least before I do), they have a moral and ethical obligation to rigorously test that hypothesis, just as they would if they were advising us all to take a drug.”

Cocovorically Yours,

-ACP

For those seeking more information.

This graph is from the BMJ paper which also included a meta-analysis of all randomized studies substituting linoleic acid for saturated fat.  The data do not favor substituting corn oil for saturated fat

F7.large

 

 

 

14 thoughts on “Beware Of More Misinformation From The American Heart Association On Coconut Oil and Saturated Fats”

  1. It might be of use to read the ENTIRE article instead of just the abstract

    http://sci-hub.bz/10.1161/CIR.0000000000000510

    CONCLUSIONS AND RECOMMENDATIONS
    The key evidence to reduce saturated fat and replace it with polyunsaturated and monounsaturated fat is summarized below:

    • Randomized clinical trials showed that polyunsaturated fat from vegetable oils replacing saturated fats from dairy and meat lowers CVD.

    • A dietary strategy of reducing intake of total dietary fat, including saturated fat, and replacing the fats mainly with unspecified carbohydrates does not prevent CHD.

    • Prospective observational studies in many populations showed that lower intake of saturated fat coupled with higher intake of polyunsaturated and monounsaturated fat is associated with lower rates of CVD and all-cause mortality.

    • Saturated fat increases LDL cholesterol, a major cause of atherosclerosis and CVD, and replacing it with polyunsaturated or monounsaturated fat decreases LDL cholesterol

    • Replacing saturated with polyunsaturated or monounsaturated fat lowers blood triglyceride levels, an independent biomarker of risk for CVD.

    • Replacing saturated with polyunsaturated fat prevents and regresses atherosclerosis in nonhuman primates.

    • Overall, evidence supports the conclusion that polyunsaturated fat from vegetable oils (mainly n-6, linoleic acid) reduces CVD somewhat more than monounsaturated fat (mainly oleic acid) when replacing saturated fat.

    Evidence has accumulated during the past several years that strengthens long-standing AHA recommendations to replace saturated fat with polyunsaturated and monounsaturated fat to lower the incidence of CVD. Reduction in total dietary fat or a goal for total fat intake is not recommended. This shift from saturated to unsaturated fats should occur simultaneously in an overall healthful dietary pattern such as the DASH or Mediterranean diet as emphasized by the 2013 AHA/American College of Cardiology lifestyle guidelines and the 2015 to 2020 Dietary Guidelines for Americans.

    Question – how much SFA as a % of their diet do you recommend your patients consume?

    1. Charles, I’m not sure if your comment implies I didn’t read the whole article. If you read my entire blog post you would see that I quote extensively from the full AHA document and the link I provided is to Circulation where the full article is easily downloaded as a PDF.
      I’m not sure what the benefit of repeating the articles conclusions is if the scientific underpinnings are suspect.

    2. Charles, I guess you didn’t read my entire blog post. If you had, you would have noted that I extensively quoted from the full AHA article which is available at the link I provided. Res-iterating the misguided conclusions from that article doesn’t make them any more correct.
      Dietary recommendations for my patients are on this site. I don’t focus on macronutrient percentages. I focus on foods that have been shown to be helpful like fish, nuts, vegetables, yogurt, cheese within dietary patterns like the Mediterranean diet.

  2. We need a controlled study: group A eats whatever they feel like and ignores all expert dietary advice; group B does the opposite. Not sure group B would win.

  3. Great casemaking.

    I personally don’t care for coconut oil.

    But I really hate shoddy analysis.

    Not sure if the AHA is being lazy or agenda-driven.

    But, if you’re going to exclude major, inconvenient studies, you should, at a minimum, give that choice an asterisk.

  4. Stop this bullshit, it all saturated fats are the same, not alcohols are the same, not all salts are the same, not all horse craps are the same, SATURATED FAT KILLS YOU.

  5. One has to question the motives in this aggressive attack on coconut oil? An all out assault on red meat eating is what is really in order. That is where Americans [ i would guess ] get 99% of their saturated fat.

    1. I think their motives are
      1. Keep to the simplistic line: easier for the public to grasp
      2. Repeat what they have said before: otherwise the public may lose confidence

  6. I shared a link to your post on my blog! Hope you don’t mind 🙂 I recommend different fat consumption levels to my clients on an individual basis. Athletes, those suffering with various auto-immune diseases, what their goals are, their food preferences, etc. There’s a lot that comes into play, especially with Keto popularity on the rise.

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