is coconut oil healthy

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COCONUT OIL ARE ITS HEALTH CLAIMS JUSTIFIED? Dr.Laurence Eyres ECG Ltd Chairman NZIC Oils and Fats Group November 2014

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COCONUT OIL – ARE ITS HEALTH

CLAIMS JUSTIFIED? Dr.Laurence Eyres ECG Ltd

Chairman NZIC Oils and Fats Group

November 2014

Is coconut oil healthy?

WHAT IS COCONUT OIL?

Edible oil industry production of commodity

crude to RBD- Own experience in 1974

Newmarket

Niche production of Extra virgin oil-definition

What’s all the fuss about? Market rapid growth

Confusion with MCT oil (Medium chain

triglycerides)

Conclusion as to the claimed health benefits

COCONUTS

Tropical fruit grown year round

Oil within the meat of the coconut

Contained within cells

Composition Percentage of Fresh Coconut Meat by Weight

Moisture 50

Oil 34

Ash 2.2

Fibre 3

Protein 3.5

Carbohydrates 7.3

COPRA EXPELLING TO FORM OIL

Typical screw presses for oil from copra

VANUATU 2014

BATCH REFINERY IN VANUATU

TRADITIONAL USES OF CNO AND HCNO

Most of the oil has been used as HCNO( the fully

hydrogenated oil -no trans!) termed a

confectionery fat. (same use as fully hardened

palm kernel oil).Increase in melt point from 26 to

35 degrees C

CF 92-kremelta-home made chocolate rice

krispies, biscuit fillings, caramels etc.

Unhydrogenated oil resurrected by marketers as

the answer to all human ills!

WEBSITE AND CELEBRITY ENDORSEMENT

OF CNO

No evidence to back claims by celebrities for

exaggeratde health claims for coconut oil.

These are statements-only anecdotal hype

Erroneous classification of coconut oil triglyceride

structure-claims based on the sound work done on

genuine MCT oil

EXTRA VIRGIN COCONUT OIL

Colourless when liquid

Characteristic mild aroma of coconut

Oil quality

Acid Value-low <4mg KOH/g oil

Measures hydrolysis of oil

Peroxide Value-low <10 meq peroxide/g oil

Measures oxidation of oil

WONG, M., EYRES, L., RAVETTI, L. 2012. Modern aqueous oil extraction: Centrifugation systems for olive and avocado oils. In: Green Vegetable Oil Processing. Editors: Proctor, A. & Farr, W. The American Oil Chemists Society, AOCS

COMPOSITION OF COCONUT OIL

Predominantly triacylglycerols

Made up of the following fatty acids

C6, 8 and 10 saturated fatty acids 17%

C12 saturated fatty acid (lauric) 47-48%

Myristic and palmitic saturated fatty acids 24%

Unsaturates 7-8%

Healthy?

IS COCONUT OIL COMPOSED OF

MEDIUM CHAIN TRIGLYCERIDES?

NO

MEDIUM CHAIN FATTY ACIDS AND

TRIGLYCERIDES

Explanation of terms

Medium chain fatty acids 8, 10 and 12 carbon fatty acids

MCT’s are comprised C8 and C10 only not C12

Coconut oil is 47-48% C12 contains virtually no MCT’s

MCT studied for their carbohydrate-like dietary

mechanism( They contain about 70% C8 and 30%C10)

Coconut oil and MCT’s are miles apart

Bach, A. C., & Babayan, V. K. (1982). Medium-chain triglycerides: an update. Am J

Clin Nutr, 36(5), 950-962.

MANUFACTURE OF MCT OIL-FROM THE

60’S

CNO or palm kernel oil are hydrolysed to their

fatty acids

These are distilled the prize is C12 fatty acid

(48%)used to make surfactants and other

chemicals-such as sodium lauryl sulphate

The residual C6,8 and 10 fatty acids are

separated (lower boiling)

They are then re-esterified back into triglycerides

Bleached and deodorised

Product is fully saturated, bland,colourless,stable

and has unique properties in nutrition

CONDENSATION – GLYCEROL

AND FATTY ACIDS-SYNTHESIS

MCT OIL-USING C8 AND C10 FA

COMPARING COCONUT OIL WITH MCT OIL

Fatty acids Coconut Medium chain triglycerides

Butyric 4:00 0 0

Caproic 6:0 1 <2

Caprylic 8:00 9 50-80

Capric 10:00 7 20-50

Lauric 12:00 47 <3

Myristic14:00 16.5 <1

Palmitic16:00 7.5 0

Stearic18:00 3 0

Oleic18:1 cis 6.4 0

Triglyceride carbon number analysis of CNO vs. MCT oil MCT oil (Croda) Coconut oil Mol Weight

Tricaproin C24 24 zero 471

TricaprylinC26 25 zero 499

Tricaprin C28 28 0.5 527

Tricaprin C30 10-10-10 10 3 555

C32 <3 14 583

C34 <1 17.5 611

C36 Trilaurin LaLaLa plus others 0 20 639

C38 0 16 667

C40 0 10 695

C42 0 7 723

OLD CHROMATOGRAM SHOWING TRIGLYCERIDE

ANALYSIS BY CARBON NUMBER(MOLECULAR

WEIGHT)-1985 VINTAGE LE

PHYSICAL DIFFERENCE MCT AND CNO AT

AMBIENT

LAURIC ACID TWELVE CARBON SATURATED

FATTY ACID

Whilst chemically Lauric acid (C 12:0) could

possibly be described as a medium chain fatty

acid-biologically it behaves as a typical saturated

fatty acid like myristic and palmitic.

CONCLUSION 1

Coconut oil is NOT composed of medium chain

triglycerides

Any referring to CNO and its similarity in the

metabolism of MCT oil is erroneous and

misleading

Coconut oil does not behave the same as MCT’s

and it is totally erroneous and scientifically

wrong to call coconut oil an MCT and thus any

analogies comparing coconut oil with clinical

work on MCT’s are void.

PEER REVIEWED CLINICAL

EVIDENCE ON CNO ROLE IN CVD

We found no evidence to suggest that CNO is

beneficial other than as a source of energy

Replacement of some CNO with PUFA resulted

in more favourable lipid profiles

Coconut flesh, cream and milk when consumed

with fish, vegetables and fruit can be considered

a healthy diet

NORDIC REVIEW

There was convincing evidence that partial

replacement of SFA with PUFA decreases the

risk of CVD, especially in men. This finding was

supported by an association with biomarkers of

PUFA intake; the evidence of a beneficial effect of

dietary total PUFA, n-6 PUFA, and linoleic acid

(LA) on CVD mortality was limited suggestive.

Evidence for a direct association between total

fat intake and risk of T2DM was inconclusive,

whereas there was limited-suggestive evidence

from biomarker studies that LA is inversely

associated with the risk of T2DM.

LITERATURE SEARCH

Searches were conducted in the Scopus and

Medline databases and bibliographies in

published literature and on websites promoting

coconut oil were examined. The few papers and

studies (n=23) identified for inclusion in this

review demonstrates the paucity of quality

studies, reviews or meta-analyses that examine

the effects of coconut in its own right. Even fewer

have studied the effects of consumption of

coconut or coconut products on cardiovascular

disease outcomes.

CONCLUSION 2

No evidence from human clinical trials to suggest

that CNO can be classified as a healthy oil

SUMMARY CLINICAL PAPERS REVIEW

In summary, while the level of evidence on coconut itself and risk factors for heart disease is mostly poor quality, the evidence suggests that consumption of coconut oil raises total cholesterol, HDL and LDL, although in clinical trials this did not raise them as much as butter.

In the clinical trials included in this review, the effects of coconut oil on triglyceride levels versus unsaturated oils were generally not significant.

Cox, C., Sutherland, W., Mann, J., de Jong, S., Chisholm, A., & Skeaff, M. (1998). Effects of dietary coconut oil, butter and safflower oil on plasma lipids, lipoproteins and lanosterol levels. Eur J Clin Nutr, 52(9), 650-654.

CONCLUSION 3

For consumers living in New Zealand who are on

a Western style diet, based on current evidence it

would be inadvisable to switch from unsaturated

oils to coconut oil. It is likely that this would lead

to less favourable lipid profiles and so a potential

increased risk from CHD.

RECOMMENDATION

Consumers who are using a lot of coconut oil due

to the current fad would be well advised to either

limit its use, or to blend in some unsaturated cold

pressed monounsaturated oils such as olive,

avocado or canola oil. Although it may be a better

choice than butter, coconut oil cannot be

recommended as a suitable alternative to non-

hydrogenated vegetable oils.

http://www.heartfoundation.org.nz/uploads/Evi

dence_paper_coconut_August_2014.pdf

POPULATION STUDIES

Indigenous populations who consume traditional diets with coconut products along with fish and vegetables (unsaturated fats and fibre) combined with a physically active lifestyle are unlikely to be at risk of cardiovascular disease from the consumption of coconut products. The situation for indigenous populations who eat a traditional diet is vastly different to that of people consuming a typical “Western” diet.

For other populations, coconut oil is 92% saturated and nothing in the literature disputes the fact that it acts as a saturated fat and raises total cholesterol, LDL cholesterol and HDL cholesterol.

CONCLUSION 4

Pacific island populations have not normally consumed coconut oil per.se., instead coconut oil is consumed as a component of coconut flesh or coconut milk.

The Pacific Island communities have had their traditional diets modified enormously and high fat and high sugar processed foods have been incorporated into their local culinary culture with adverse effects on obesity and health. Making changes in the food supply to improve access and availability of locally produced traditional foods may allow taste preferences to be met and may be a better option than encouraging behaviour change alone.

HOW TO HAVE A HEART

ATTACK

WRITTEN REVIEWS

NZ Heart Foundation website

Food New Zealand-October and December issues

Oils and fats website

http://www.oilsfats.org.nz/ For Oils and Fats

Group