Compiled and coordinated by Edward Arambewala
Ceylon Medical Journal on coconut fats
There is the need to clarify issues relating to intake of coconut
fats and health, more particularly for populations that still depend on
coconut fats for much of their fat intake.
This paper describes the metabolism of coconut fats and its potential
benefits, and attempts to highlight its benefits to remove certain
misconceptions regarding its use.
Coconut consumption and lipid patterns in Sri Lanka
A recent study has shown that in Sri Lanka, whereas 91 per cent of
the poor still consume coconut as their main source of fat, only 70 per
cent of those earning more than Rs. 5,000 use coconut oil.
The amount of coconut consumed is less than 5 years ago for 75 per
cent of those surveyed. Thus study also found that one of the reasons
for reduced coconut consumption was a misconception that coconut fats
are bad. The misconception has arisen due to the fact that coconut fat
is mainly saturated fat, and saturated fats are synonymous with
atherosclerosis, ischaemic heart disease and cerebrovascular disease.
There remains the question whether coconut fats have actions other
than those in relation to lipid hypothesis of atherosclerosis, ischaemic
heart disease and cerebrovascular disease which need to be considered
when answering the above question. Ischemic heart disease
To answer that, one would have to first look at coconut consumption
and possible relationship to the prevalence of ischaemic heart disease
and cerebrovascular disease in Sri Lanka. Kaunitz states that the
Demographic Yearbook of the United Nations (1978) reported that Sri
Lanka has the lowest death rate from ischaemic heart disease.
Sri Lanka was quoted as being the only country giving reliable data
where coconut oil is the main dietary fat. This was at a time when
average coconut consumption was around 130 nuts/person/year.
On the other hand, according to Abeywardena, the incidence of
ischaemic heart disease and cerebrovascular disease in Sri Lanka is
increasing at an alarming rate and is similar to that of the developed
world. Central Bank of Sri Lanka reports show that the coconut
consumption has now declined to around 100-110 nuts/person/year.
Are coconut fats the culprit
Under the circumstances, are coconut fats the culprit or have they
been given a bad name simply by virtue of its fat being greater than 90
per cent saturated fat?
Epidemiologic studies both in Sri Lanka and elsewhere, have failed to
clearly establish a relationship between coconut fats, atherosclerosis
and ischaemic heart disease.
The classic study by Prior among Pacific islanders whose diet
contained large amounts of coconut showed a low prevalence of heart
disease, cancer, diabetes and arthritis.
Mendis has attributed this to a 'protective effect' of omega-3 fatty
acids from the fish these people ate. Other, more recent studies on
small population samples have failed to establish a clear link between
consumption of coconut products and atherosclerosis, ischaemic heart
disease and cerebrovascular disease.
Case control studies comparing the diet of patients with ischaemic
heart disease and controls have come out both for and against a
causative role for coconut fats.
Coconut fats and lipids
The possible role of coconut fats in disturbances of lipid metabolism
is also not well established. Many allopathic medical practitioners seem
to think that, as coconut fats are saturated, they elevate plasma lipids
in the same manner as the saturated fats from animal sources.
Adding to the misconception is the fact that many of the animal
studies on the role of coconut fats in lipid metabolism have used
hydrogenated coconut oil. This is an unnatural form of coconut oil that
is purposely altered to make it completely devoid of any essential fatty
acids.
The conclusion that can be drawn from such animal research is that
feeding hydrogenated coconut oil devoid of essential fatty acids
enhances the formation of atherosclerosis markers. However, coconut oil,
unlike much of the soybean and corn oil consumed both here and abroad,
is free of hydrogenated fat and hence transfatty acids.
In human feeding studies, coconut fats without doubt elevate high
density lipoprotein (HDL) cholesterol. The effect on total cholesterol
and low density lipoprotein (LDL) cholesterol is probably neutral. It is
also possible that women may react differently to men when fed a coconut
diet.
A Sri Lankan study found that the risk of coronary heart disease as
assessed by the body mass index, ratios of total cholesterol to HDL-cholesterol,
and LDL-cholesterol to HDL-cholesterol, was significantly lower in
subjects in rural areas, who were agricultural workers with a high
degree of physical activity, subsisting on a diet consisting mainly of
plant food, despite a higher consumption of coconut, a saturated fat.
This study also suggest that hyperlipidaemia is more common among
urban dwellers than among the rural population. This difference was
attributed to lower fruit, vegetable and fibre content in the diet and
lower physical activity among the urban population. Yet from Peiris'
study we know the rural poor consume more coconut than city dwellers.
Abeywardena has proposed that a low fat diet with predominantly
coconut fat may lead to the 'metabolic syndrome' and thus be associated
with the increasing prevalence of ischaemic heart disease and
cerebrovascular disease. However, this needs to be proven by good
epidemiologic studies.
Virgin coconut oil when fed to rats is reported to lower lipid levels
in serum and tissues, and LDL oxidation.
This property of virgin coconut oil is attributed to the biologically
active polyphenol components present in the oil. Other studies have
shown that consumption of a solid fat rich in lauric acid gives a more
favourable serum lipoprotein pattern than consumption of partially
hydrogenated soybean oil rich in trans-fatty acids.
Other effects of coconut oil
What of the claim that coconut fats decrease platelet adhesiveness?
Hard data are not readily available. A 1993 study comparing a high fat
diet (50 per cent of total energy) to a low fat diet (20 per cent)
suggested that the high fat diet might increase blood thrombogenicity by
virtue of augmented postprandial activation of factor VII. A more recent
2003 study showed that a lesser increase in FVIIa occurred after the
consumption of saturated fats, than after unsaturated test fats.
Others have attempted to study the effects of individual fatty acids
on whole blood aggregation and concluded that compared to oleic acid,
lauric, myristic or palmitic acids do not effect in vitro whole blood
aggregation induced by collagen ADP-induced aggregation.
Compared to a high unsaturated fat or high polyunsaturated fat diet,
a coconut oil-based diet lowers postprandial t-PA antigen concentration,
and this may favourably affect the fibrinolytic system and the Lp (a)
concentration.
What of other benefits that may accrue from eating coconut oil? Many
readers may not be aware of the close similarity among the medium chain
triglycerides in coconut fats, human breast milk and the secretion of
sebaceous glands, all rich in lauric acid.
Monolaurin and even lauric acid have been shown to be bactericidal,
particularly against Helicobater pylori, Vibrio cholerae, Salmonella
typhi, Shigella sonnei and enterotoxigenic Escheichia coli. coconut oil
also helps the body to increase absorption of calcium and magnesium
ions.
It has been suggested that coconut oil is used to supplement
treatment of rickets in poorly developed countries, alongside infant
formulae supplemented with these inorganic ions.
No work has been done with coconut fats per se. However, it is
interesting to speculate whether monolaurin and lauric acid released by
pre-gastric lipase may contribute to the reported low incidence of
Helicobacter pylori infection in Sri Lanka compared to other South Asian
countries.
Immune system
Current understanding based on the effect of dietary lipid
manipulation upon immune system function indicates that fatty acids are
involved in the modulation of the immune response through complex
pathways.
The problem with many animal studies is that they use hydrogenated
coconut oil. One study where non-hydrogenated coconut oil was used
showed that lipopolysaccharide-stimulated TNF-alpha production by
macrophages decreased with increasing unsaturated fatty acid content of
the diet.
World peace flag with baby emblem -D.W.A.
Doctors Wives Association will call for the adoption of a flag by the
UN with a baby just born emblem, as the UN peace flag for the whole
world, if possible.
This will be done this Sunday at the HealthWatch children's crossword
draw on peace and amity to be held at the Wijerama Mawatha auditorium of
the SLMA.
The DWA president Chrissy Aloysius said this follows a poem on the
subject published in the Poetry Corner of the Daily News on January 25,
2006 by the HealthWatch, coordinator under the 'Just Born' heading,
calling for the necessity to change the present peace emblem of the
dove, to a baby just born as the emblem and make it the peace flag for
the whole world, which the DWA felt was a very timely need, and a very
simple and realistic step towards peace and unity in the world which the
women folk should take up, and push forward.
She said "We discussed this and at our last meeting we had one of our
members Nalini de Alwis to carry a baby and show the world how
realistically and movingly it depicts how the people in the world could
be moved to gather around a baby for peace and unity flag."
Healthwatch childrens special & Medical Crossword No. 25 Draws on
Sunday June 10
Health watch two crosswords childrens special & Medical Crossword No.
25 Draws will be held this Sunday June 10th at 10 a.m. at the SLMA (Sri
Lanka Medical Association) Auditorium at No. 6 Wijerama Mawatha Colombo
7.
The Childrens Crossword is sponsored by Doctors Wives Association Sri
Lanka and the Medical Crossword by Novartis Medical Nutrition.
Doctors Wives Association President Mrs. Chrissy Aloysius with her
committee will conduct the draw.
The two children who drew the grids for the childrens crossword Sadun
Tikiribandara, year 3, Ananda College Colombo and Viraji Bandara, year
13, Visakha Vidyalaya, Colombo, will be given their prizes for the grids
at this event, while the prize winners of medical crossword No. 24 drawn
at the Colombo Apollo Hospital Auditorium on 25-11-2006 will also be
presented with their prizes at this draw on Sunday.
The prize winners whose names were carried in the Health Watch of
Dec. 2nd, 2006 are Health Watch Medical Crossword Draw No. 24
Prize Winners
Prize winners of Novartis Medical Nutrition sponsored Health Watch
Medical Crossword Draw No. 24 held at Colombo Apollo Hospital at
Narahenpita on Saturday, November 25.
1st prize Rs. 3,000
G. Martil (Entry No. 34)
17/1, Ananda Balika Mawatha,
Pita Kotte.
2nd prize Rs. 2,000
Bernie Peris (Entry No. 14)
27, Richard
Pamunuwa Mawatha,
Matale.
3rd price Rs. 1,000
Damayanthi Seneviratne
(Entry No. 25), 33, Malwatte Road, Matale. Consolation prizes from
Apollo Hospital, Narahenpita Three Medical check-ups at Colombo Apollo
Hospital 1. Andrena G. Fernando (Entry No. 40) 78/1, Ananda Balika
Mawatha, Pita Kotte.
2. N. P. Sumitha Nilmini (Entry No. 20) Mariyawila Estate, Puttalam
Road, Buttulu Oya.
3. Suresh Pararajasingham (Entry No. 66) 33/E/16, Mihindu Mawatha,
Malambe.
Consolation prizes from Novartis Med-Nutrition Medical Nutrition
Packs 1. F. J. Ratnayake (Entry No. 4), 25/13, Kalinga Mawatha,
Polhengoda, Colombo 5.
2. Manesha de Silva (Entry No. 55), 'Windsor Tower', No. 81/1/6 Ward
Place, Colombo 7.
3. Jegatheswari Nagendran Entry No. 54) 33/3, De Fonseka Place,
Colombo 5.
Consolation prize of Rs. 1,000 each from Parkway Healthcare group
Services, Colombo office 1. Antonette Ferdinand (Entry No. 29) 25,
Dharmaratne Avenue, Rawathawatte, Moratuwa.
2. M. H. Mohamed Yakooth (Entry No. 30) 65/87, Crow Island, Colombo
15.
3. Lakshman Peiris 27, Richard Pamunuwa Mawatha, Matale. Best wishes
and our congratulations to all the prize winners, and to all others who
sent entries to this.
Foreign doctors likely to sit local diploma in Clinical Hypnotism
The local diploma course in clinical hypnotism conducted by the Sri
Lanka College of General Practitioners (CGP) is likely to be taken up by
several doctors in India and Pakistan shortly. This was revealed to the
HealthWatch by the head of the CGP Clinical Hypnotic Examination Unit,
Dr. H. B. Jayasinghe. He said that several requests made by doctors in
these two countries to follow this course and sit the examination is now
being taken up by the CGP with the PGIM. Last week the CGP had its
Diploma examination for Clinical Hypnotism for local doctors for the
third year. These doctors have to undergo one year training course at
the CGP before they sit the exam. This year, six doctors took up this
diploma examination. At present there are 26 doctors in the country who
have passed this exam and practising this therapy. |