Is coconut oil better for your heart than typical vegetable oils?

Question

A co-worker of mine is a born-again health nut, and I recently overheard him espousing to other co-workers that all their cooking should be done with coconut oil as it's full of "good" fats.

Knowing from a couple of sources that coconut oil's fat content is, by weight, more than 90% saturated fats, which are most definitely not "good", I raised my voice in dissent. Saturated fats and cardiovascular disease have been linked in multiple health studies, and so the FDA, USDHHS, and counterpart ministries of the UK, Australia, New Zealand, Hong Kong, Singapore and India all recommend minimizing saturated fat intake.

As backup for his claims, my co-worker referenced, wonder of wonders, Dr Oz. I have generally taken anything the good doctor says with more than one grain of salt, and I'm not alone: Popular Science and Salon (covering different extremes of magazine readership demographics) have both run columns with much the same conclusion; following Dr. Oz can be harmful to your health.

I might be able to agree with the claim that coconut oil, because its saturated fats are by definition not trans-fatty acids (only unsaturated fats can have a double C=C bond in the "tail" of the fatty acid, and thus exhibit cis-trans isomerism), might be better than partially-hydrogenated vegetable oils (such as margarine) which exhibit unnaturally high trans-isomer content. But to say unequivocally that coconut oil is good for you and you should replace as much of your fat intake as possible (such as from cooking fats) with coconut, when coconut oil has the highest saturated fat content of any vegetable oil, worse than butter, much worse than olive or canola, I just can't see eye to eye with this guy.

Putting the question to you, What studies, other than ones Dr Oz has authored or peer-reviewed, say that coconut oil is a healthy thing to be eating in lieu of other forms of fats, and have any of them been debunked, retracted or discredited by studies showing the exact opposite?

Answer 1

Do not consider the name of the fat but rather its effect on cholesterol. Lauric acid, a saturated fat and the major constituent in coconut fat, raises serum cholesterol considerably. However, it almost entirely raises HDL cholesterol, meaning the net effect is a higher total cholesterol, but a much "healthier" cholesterol composition. They don't know if this is good or bad yet.

Effects of dietary fatty acids and carbohydrates on the ratio of serum total to HDL cholesterol and on serum lipids and apolipoproteins: a meta-analysis of 60 controlled trials - http://ajcn.nutrition.org/content/77/5/1146.short

Answer 2

I don't have a reference to studies showing consuming coconut oil is healthier than other plant oils, but I do have one that showed it was worse which is what you also asked.

In this 5 week cross-over 3x3 Latin square design study of diets high in palmitic oil, extra-virgin olive oil, and coconut oil [1], the coconut oil diet showed significantly higher fasting and post-prandial total cholesterol. In addition homocysteine levels were higher in the coconut oil group though not significantly so. IL-6 was also higher but hs-CRP was not which is curious since c-reactive protein synthesis is driven by Interleukin-6.

Ian Prior's study from 1981 appears to clearly show the cholesterol raising effects of coconut oil consumption. His group compared the lipids of those islanders living on the Pacific islands of Pukapuka and Tokelau where coconut oil was the main source of dietary energy. The Tokelauan diet was then unique with more than 50% of energy mainly derived from saturated fat ( coconut oil ), whereas in comparison the Pukapukans was much lower at 35%. Dietary intake of cholesterol was low. It was presumed that as a result the Tokelauans were heavier, and at all age groups had significantly higher levels of cholesterol (35-40 mg/L). Although the abstract states that

Vascular disease is uncommon in both populations

and this is quoted by various papers to make a case for consuming coconut oil, the paper actually states that they took 12 lead ECGs on both groups and estimated ischemic heart disease based on the presence of Q waves, and then stated the number they studied was too small to make a definitive statement. As we know now, using ECG for diagnosis of ischemic heart disease is very unreliable.

PS: I don't have enough rep to comment on the answer by @Heliotrope but this study does not show what he claims regarding raising HDL much more than LDL. And we also know that all the drug trials on raising HDL have not lead to improved outcomes. Presumably because there is a higher limit at which having HDL is helplful. Also the rise in HDL occurs because HDL is involved in reverse cholesterol transport, so if you consume more fat, then HDL is obliged to rise as well.

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[1] Voon PT, Ng TK, Lee VK, Nesaretnam K. Diets high in palmitic acid (16:0), lauric and myristic acids (12:0 + 14:0), or oleic acid (18:1) do not alter postprandial or fasting plasma homocysteine and inflammatory markers in healthy Malaysian adults. Am. J. Clin. Nutr. 2011 Dec;94(6):1451-7. doi: 10.3945/ajcn.111.020107. PubMed PMID: 22030224.

[2] Prior IA, Davidson F, Salmond CE, Czochanska Z. Cholesterol, coconuts, and diet on Polynesian atolls: a natural experiment: the Pukapuka and Tokelau island studies. Am. J. Clin. Nutr. 1981 Aug;34(8):1552-61. PubMed PMID: 7270479.