Coconut Oil: Greasing the Skids to Wellville or Clogging the Arteries To the Heart

While the skeptical cardiologist was wandering around in ketoland, he acquired a large jar of extra virgin coconut oil for the purpose of boosting his fat consumption. He stirred spoonfuls of the solid waxy substance into his coffee and applied it to various and sundry skin rashes.
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%) and thus contributes to heart disease.
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.
The problem with this simplistic message is that the kind of saturated fat in CO differs markedly from both dairy SFAs and beef SFAs and, like dairy fat, appears to have a beneficial effect on blood lipids, weight, and cardiovascular health.

Misguided Dietary Fat Recommendations

The AHA guidelines, for example, recommend 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 last month in the BMJ, (don’t get me started on why these data were “buried” for decades).
Data from this study, which substituted liquid corn 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.

Very Brief (But Seemingly Unavoidable) Digression Into Organic Chemistry Featuring Obscure But Intriguing Chemical Names and Numbers to 5.0 Significant Digits

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). Take a look at the complex mixture of saturated fatty acids present in virgin coconut oil and note lauric acid (green) and palmitic acid (red):

Fatty acid profileConcentration (%)
C6Caproic2.215
C8Caprylic12.984
C10Capric6.806
C11Undecanoic0.028
C12Lauric47.280
C13Tridecanoic0.030
C14Myristic15.803
C15Pentadecanoic0.006
C16Palmitic6.688
C16 : 1Heptadecanoic0.011
C17Stearic0.011
C18Oleic1.481
C18 : 1n9cElaidic5.073
C18 : 1n9tLinoleic0.231
C18 :  2n6cLinolelaidic1.168
C18 : 2n6tγ-Linolenic0.045
C18 : 3n6gα-Linolenic0.007
C18 : 3n3aArachidic0.013
C20Cis-11-Eicosenoic0.039
C20 : 1n9Behenic0.039
C22Cis-13,16-Docisadienoic0.006
C24Lignoceric0.020

Palmitic acid, a long chain FA with 16 carbon atoms, makes  up only  7% of coconut oil, but is the major SFA in dairy and beef fat. When consumed in isolation, it raises the LDL or bad cholesterol and the ration of LDL to HDL, and thus has been labeled as unhealthy. Of course, as pointed out here we don’t consume either palmitic acid or lauric acid in isolation; we consume them in the complex milieu of other fats, antioxidants, proteins and carbohydrates that we call food.
Medium chain fatty acids, and especially lauric acid, do a really good job of raising the good HDL cholesterol and lowering the ratio of LDL to HDL, changes which should boost heart health.

Detailed Explanation of Differential Long and Medium Chain Fatty Acid Absorption and Metabolism (Feel Free to Skip)

Looking closely at the metabolism of MCSFAs we find:

” MCFAs are rapidly absorbed in the intestines even without catalyzation by the pancreatic lipase enzyme. LCFAs, on the other hand, required pancreatic lipase for absorption. They are carried by the lymph to the systemic circulation in chylomicrons and eventually reach the liver where they either undergo beta oxidation, biosynthesis to cholesterol, or are repackaged as triglycerides. MCFAs are carried by the portal vein to the liver where they are rapidly oxidized to energy. Unlike LCFAs, MCFAs do not enter the cholesterol cycle and they are not deposited in fat depots.”

Benefits of Coconut Oil, Cardiovascular and Otherwise

If you’d like to read a lot of hype and mumbo-jumbo about the benefits of coconut oil, I suggest you start at coconutoil.com and take a look at this graphic:Coconut-Oil-Health-Benefits
 
After a little reading, you will be ready to smear coconut oil all over your body and consume heaping spoonfuls thrice daily.

pastedgraphic-3_custom-0c04b15858d6b64ecbb597e1a17940ae72e34449-s400-c85
August Engelhardt stands underneath a palm tree with Berlin concert pianist Max Lützow at his feet. Lützow went to Kabakon to join Engelhardt’s sun-worshipping cocovore cult, The Order of the Sun. He died there, as did several other followers.

Be careful, though, you may end up like German nudist August Englehard who believed “that since the coconut grew high up in the tree, closest to God and closest to the sun, it was godlike, And since it had hair and looked like a human head, he thought it came closest to being a man. According to his rather crackpot theory, to be a cocovore was to be a theophage — or eater of God.”
My favorite article on the potentially atherogenic effects of coconut oil is entitled “Atherogenic of Not? (What therefore causes atherosclerosis?)  published in the Philippine Journal of Cardiology in 2003:
Screen Shot 2016-05-07 at 12.07.41 PM
The author, a prominent Phillipino cardiologist inserted the Phillipines (note my big red arrow) data into the famous Ancel Keys graph which plots heart disease mortality rate versus percent calories from fat.

The data point of the Phillipines, where coconut oil is the predominant cooking oil, totally disrupts the relationship between dietary fat and heart disease.
Of course, scientists now know that these kinds of correlations prove nothing, but they were the basis for guiding Americans to low fat, high carbohydrate manufactured monstrosities.

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.
I doubt that few if any of the miraculous  CO benefits hyped at coconutoil.com and elsewhere are real but if it helps your skin or your scalp, your digestion or your taste buds, feel free to consume ad lib and don’t worry about any adverse effects on your coronary arteries or your heart.
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
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Here is a primer on SFA sources and effects on cholesterol from a recent review on dairy fat and cardiovascular disease.
/After absorption, the predominant dairy SFA palmitic acid (C16:0), but also myristic acid (C14:0) and lauric acid (C12:0) are preferentially directed to TG formation rather than to phospholipid acylation. These three long-chain fatty acids raise total cholesterol, but their effects on LDL:HDL ratios are different. Palmitic acid is the major SFA in the diet and also in milk fat with a content of about 30%. Palmitic acid raises the LDL cholesterol more than it raises HDL cholesterol (27). Myristic acid represents 11% of the dairy fatty acids and increase total cholesterol as much as palmitic acid, but does not affect total cholesterol:HDL ratio (128). Lauric acid is the most potent fatty acid in raising plasma total cholesterol, but dairy content is only 3.3%. The increase in HDL cholesterol induced by lauric acid is higher than the increase in LDL and thus the total cholesterol:HDL ratio was decreased when lauric acid was used to replace carbohydrates (1). Stearic acid represents 12% of the dairy fatty acids and improves the plasma cholesterol profile by decreasing total/HDL cholesterol ratio compared to other SFAs. But compared to polyunsaturated fatty acids (PUFA), stearic acid increases LDL and decreases HDL and increase total/ HDL ratio. (29). Other SFAs are short- and medium-chain length and are mainly considered to be cholesterol neutral. At a certain amount of SFA intake, an increase in both LDL and HDL cholesterol can be seen, especially if the intake of unsaturated fatty acids is low (3031). In a recent meta-analysis of prospective epidemiological studies, intake of SFA and risk of CVD was studied (32). Six studies found a significant positive association between SFA intake and CVD, and 10 studies found no significant association.
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16 thoughts on “Coconut Oil: Greasing the Skids to Wellville or Clogging the Arteries To the Heart”

  1. Hi Doc,
    So many different thoughts could make ones head spin. Are theree any articles–thoughts, on Dr McDougall and his staff. Jeff Novick provides lots of credible studies debunking coco oil, among others. Sure you know, they are in the starches camp, potatoes, beans, rice corn, etc. no dairy, fish, meat, and have many who follow their way and have great results, hard to argue with i’d think.
    The keto, paleo, crews show one could lose weight, for sure as i’ve seen many who do, and make some claims (one keto Dr. has a book “the cancer cleanse”) but i haven’t seen results from people, just his claims.
    Makes sense, no/low sugar, carbs, all “supposedly” cancer promoters. I say supposedly cause i don’t know. (not talking refined sugars)
    Thanks for listening, looking forward to your thoughts.
    Best in health
    Mike

    Reply
    • Jeffrey,
      I’ve talked about Ornish’s studies in a reply to comments to either my Pritikin ()or Esselstyn post.
      Here it is:
      I’m saying there is no good evidence to support the Ornish/Pritikin/Esselstyn diet. I’ve commented on the lack of good studies supporting Esselsytyn’s claims ().
      The Ornish claims are based on a study he performed between 1986 and 1992 which originally had 28 patients with coronary artery disease in an experimental arm and 20 in a control group.
      The experimental patients received “intensive lifestyle changes (10% fat whole foods vegetarian diet, aerobic exercise, stress management training, smoking cessation, group psychosocial support).
      The control group had none of the above.
      Ornish likes to tout this as showing “reversal of heart disease” because at one year the average percent coronary artery stenosis by angiogram had dropped from 40% to 37.8% in the intensive lifestyle group and increased from 42.7% to 46.1% in the control patients.
      In other words the “reversal” was minuscule.
      Furthermore, dropping coronary artery blockages by 5 or 10% doesn’t really matter unless that is also helping to prevent heart attacks.
      There were no significant differences between the groups at 5 years in hard events such as heart attack or death.
      In fact 2 of the experimental group died versus 1 of the control group by 5 years (?suicide)
      Ornish’s Lifestyle Intervention is not a trial of diet.
      It is a trial of multiple different factors with frequent counseling and meetings to reinforce and guide patients.
      Since investigators clearly knew who the “experimental patients” were and they were clearly interested in good outcomes in these patients there is a high possibility of bias in reporting outcomes and referring for interventions.
      This study has never been reproduced at any other center.
      Because of the small numbers, lack of true blinding, lack of hard outcomes and use of multiple modalities for lifestyle intervention, this study cannot be used to support the Ornish/Esselstyn/Pritikin dietary approach.
      Consequently, you will not find any source of nutritional information or guideline (unless it has a vegan/vegetarian philosophy or is being funded by the Ornish/Pritikin lifestyle money-making machines) recommending these diets.

      Reply
  2. I recently learned that the scientific study word “significant” has a different meaning than the common usage of the word significant. Donald Trump has caused significant disruption in the Republican Party, for instance means a different thing than “Six studies found a significant positive association between SFA intake and CVD, and 10 studies found no significant association.” The science significant means “probably (>95% likely) caused by the thing we are studying” not “meaningful in a mathematical sense”. I always thought when they said a significant association it meant that it has a strong affect on the chances of something, but I was always wrong.

    Reply
  3. This is fascinating. It’s not like these upside-down protocols, guidelines and “professional” admonitions and advice haven’t had a devastating impact on our lives.
    It has me wondering what the next disclosure of dishonesty is going to be. How do I decide whom to trust?
    But, a coconut slick floating on your coffee? That has to be more dry humor, yes?

    Reply
  4. By the way, that graph about the Philippines shows only other developed countries. I don’t know if you’ve ever been there but the PI could never be confused with a developed country. Isn’t it possible the cardiac mortality rate is low because people are dying of tons of other stuff that simply isn’t seen much in the other countries on this graph?

    Reply
    • It could be any of number of things. That’s the weakness with these kind of graphs and analyses. But this was the kind of evidence that Ancel Keys used to bully dietary guidelines committees to start telling Americans to cut out the fat.
      I am definitely not saying this proves coconut oil reduces heart disease, I just thought it was an ironic way to defend its consumption.

      Reply
  5. I saw that suppressed article about the corn oil. To me that’s the best kind of evidence — when a biased researcher does a study showing the opposite, and the study is so well-designed that publishing it means the end of his career and so he suppresses is, that’s pretty compelling.

    Reply
    • Yes. The recclamation, analysis and publication of these data is remarkable. Says a lot about the biases in publication. I have a lot of negative research studies that I didnt’t publish from my research/academic days.

      Reply

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