On the Mythical Properties of Coconut Oil

My dear wife has the book, Eat Fat, Lose Fat, by nutritionist Mary Eng and Sally Fallon. This book advocates oil-centric diets with scientific-seeming arguments about the benefits of coconut oil. It reads like faddish pseudoscience to me, although I think it is well established that Atkin's like high fat diets do lead to weight loss -- although at the expense other negative health effects.

Coconut oil, while a saturated fat, is made from shorter chain fatty acids, and it is more easily metabolized by the liver than longer fatty acids, most especially palmitic or oleic.

I think that the widespread negative opinion of coconut oil was informed by data like the fatty acid source table at the bottom of this post. That table that lumped all saturated acids shorter than C-16 together. That table certainly makes coconut oil seem awful. Learning that there are more medium length oils reopens the topic.

There is a very sensible article on coconut oil by Craig Hassel on the University of Minnesota website. He addresses the coconut oil fad, and concludes that it is not as bad as people thought a decade ago. While coconut oil contains 60% medium fatty acids of C-12 or less, it also contains 40% palmitic and myristic acids which are known to increase blood cholesterol. His point about the health effect of coconut oil, that it depends the other food which coconut oil displaced in the diet. If one replaces butterfat with coconut oil, great. If one replaces olive oil, then the effect on cholesterol will be negative.

This conclusion avoids the discussion of the secondary medical benefits of the acids, most specifically caprylic and lauric. I need to read up on that further. Caprylic is only present at 12% though. My intuition is that caprylic acid may be more medicinal than other fatty acids, and that it should be used with care: in controlled amounts.


Source:

Table of Fatty Acids
Acid Name	Structure	Melt Point	Graphic	Chime
SATURATED
Lauric	CH3(CH2)10COOH	+44	Graphic	Chime
Palmitic	CH3(CH2)14COOH	+63	.	Chime
Stearic	CH3(CH2)16COOH	+70	Graphic	Chime
UNSATURATED
Oleic	CH3(CH2)7CH=CH(CH2)7COOH	+16	Graphic	Chime
Linoleic	CH3(CH2)4(CH=CHCH2)2(CH2)6COOH	-5	Graphic	Chime
Linolenic	CH3CH2(CH=CHCH2)3(CH2)6COOH	-11		Chime
Arachi- donic	CH3(CH2)4(CH=CHCH2)4(CH2)2COOH	-50	Graphic	Chime

Data from: http://www.elmhurst.edu/~chm/vchembook/551fattyacids.html

Below is an even better table:

.		fatty acid percentage in oil
Seeds		Polyunsaturated			Monounsaturated	Saturated
Name	Fat Content in seed (%)	LNA 18:3w3 (%)	LA 18:2w6 (%)	LNA+LA w3+w6 (%)	18:1w9 (%)	18:0 (%)	16:0 (%)	Total (%)
hemp	35	20	60*	80	12	2	6	8
chia	30	30	40	70	-	-	-	-
kukui	30	29	40	69	-	-	-	-
flax	35	58	14	72	19	4	5	9
pumpkin	46.7	0-15	42-57	57	34	0	9	9
soybean	17.7	7	50	57	26	6	9	15
walnut	60	5	51	56	28	5	11	16
wheat germ	10.9	5	50	55	25	18	0	18
evening primrose	17	-	81**	81	11	2	6	8
safflower	59.5	-	75	75	13	12	-	12
sunflower	47.3	-	65	65	23	12	-	12
grape	20	-	71	71	17	12	-	12
corn	4	-	59	59	24	17	-	17
sesame	49.1	-	45	45	42	13	-	13
rice bran	10	1	35	36	48	17	-	17
cottonseed	40	-	50	50	21	25	-	25
rape(canola)	30	7	30	37	54***	7	-	7
peanut	47.5	-	29	29	47	18	-	18
almond	54.2	-	17	17	78	5	-	5
olive	20	-	8	8	75	16	-	16
avocado	12	-	10	10	70	20	-	20
coconut	35.3	-	3	3	6	0	91	91
palm kernel	35.3	-	2	2	13	0	85	85
beech	50	-	32	32	54	8	-	8
brazil	66.9	-	24	24	48	24	-	24
pecan	71.2	-	20	20	63	7	-	7
pistachio	53.7	-	19	19	65	9	-	9
hickory	68.7	-	17	17	68	9	-	9
filbert	62.4	-	16	16	54	5	-	5
macadamia	71.6	-	10	10	71	12	-	12
cashew	41.7	-	6	6	70	18	-	18
neem	40	1	20	21	41	20	-	20

* Includes up to 2% GLA - Gamma Linolenic Acid

** Includes 9% GLA

*** Includes up to 5%erucic acid

* Includes up to 2% GLA -
Gamma Linolenic Acid

** Includes 9% GLA

*** Includes up to 5%erucic acid