A New Look At Coconut Oil
by Mary G. Enig, Ph.D.
Health and Nutritional Benefits from Coconut Oil:
An Important Functional Food for the 21st Century
Presented at the AVOC Lauric Oils Symposium, Ho Chi Min
City, Vietnam, 25 April 1996
Abstract
Coconut
oil has a unique role in the diet as an important physiologically functional
food. The health and nutritional benefits that can be derived from consuming
coconut oil have been recognized in many parts of the world for centuries.
Although the advantage of regular consumption of coconut oil has been
underappreciated by the consumer and producer alike for the recent two
or three decades, its unique benefits should be compelling for the health
minded consumer of today. A review of the diet/heart disease literature
relevant to coconut oil clearly indicates that coconut oil is at worst
neutral with respect to atherogenicity of fats and oils and, in fact,
is likely to be a beneficial oil for prevention and treatment of some
heart disease. Additionally, coconut oil provides a source of antimicrobial
lipid for individuals with compromised immune systems and is a nonpromoting
fat with respect to chemical carcinogenesis.
I. INTRODUCTION
Mr. Chairman and members of the ASEAN Vegetable Oils Club, I would like
to thank you for inviting me to participate in this Lauric Oils Symposium.
I am pleased to have the opportunity to review with you some information
that I hope will help redress some of the anti-tropical oils rhetoric
that has been so troublesome to your industry.
I will be covering two important areas in my presentation. In the first
part, I would like to review the history of the major health challenge
facing coconut oil today. This challenge is based on a supposed negative
role played by saturated fat in heart disease. I hope to dispel any acceptance
of this notion with the information I will present to you today. I will
show you how both animal studies and human studies have exonerated coconut
oil of causing the problem.
In the second part of my talk I will suggest some new directions where
important positive health benefits are seen for coconut oil. These benefits
stem from coconut oil's use as a food with major antimicrobial and
anticancer benefits. I will present to you some of the rationale for this
effect and some of the supporting literature.
The health and nutritional benefits derived from coconut oil are unique
and compelling. Although the baker and food processor have recognized
the functional advantages of coconut oil in their industries, over most
competing oils, for many years, I believe these benefits are underappreciated
today by both the producer and the consumer. It is time to educate and
reeducate all those who harbor this misinformation.
Historically, coconuts and their extracted oil have served man as important
foods for thousands of years. The use of coconut oil as a shortening was
advertised in the United States in popular cookbooks at the end of the
19th century. Both the health-promoting attributes of coconut oil and
those functional properties useful to the homemaker were recognized 100
years ago. These same attributes, in addition to some newly discovered
ones, should be of great interest to both the producing countries as well
as the consuming countries.
II. ORIGINS OF THE DIET/HEART HYPOTHESIS
Although popular literature of epidemiological studies usually attribute
an increased risk of coronary heart disease (CHD) to elevated levels of
serum cholesterol, which in turn are thought to derive from a dietary
intake of saturated fats and cholesterol. But, saturated fats may be considered
a major culprit for CHD only if the links between serum cholesterol and
CHD, and between saturated fat and serum cholesterol are each firmly established.
Decades of large-scale tests and conclusions therefrom have purported
to establish the first link. In fact, this relationship has reached the
level of dogma. Through the years metabolic ward and animal studies have
claimed that dietary saturated fats increase serum cholesterol levels,
thereby supposedly establishing the second link. But the scientific basis
for these relationships has now been challenged as resulting from large-scale
misinterpretation and misrepresentation of the data. (Enig 1991, Mann
1991, Smith 1991, Ravnskov 1995)
Ancel Keys is largely responsible for starting the anti-saturated fat
agenda in the United States. From 1953 to 1957 Keys made a series of statements
regarding the atherogenicity of fats. These pronouncements were:
"All fats raise serum cholesterol; Nearly half of total fat comes
from vegetable fats and oils; No difference between animal and vegetable
fats in effect on CHD (1953); Type of fat makes no difference; Need
to reduce margarine and shortening (1956); All fats are comparable;
Saturated fats raise and polyunsaturated fats lower serum cholesterol;
Hydrogenated vegetable fats are the problem; Animal fats are the problem
(1957-1959)."
As can be seen, his findings were inconsistent.
What was the role of the edible oil industry in promoting the diet/heart
hypothesis?
It is important to realize that at that time (1960s) the edible oil
industry in the United States seized the opportunity to promote its polyunsaturates.
The industry did this by developing a health issue focusing on Key's
anti-saturated fat bias. With the help of the edible oil industry lobbying
in the United States, federal government dietary goals and guidelines
were adopted incorporating this mistaken idea that consumption of saturated
fat was causing heart disease. This anti-saturated fat issue became the
agenda of government and private agencies in the US and to an extent in
other parts of the world. This is the agenda that has had such a devastating
effect on the coconut industry for the past decade. Throughout the 1960s,
the 1970s, the 1980s, and the 1990s, the anti-saturated fat rhetoric increased
in intensity.
What are some of the contradictions to the hypothesis blaming saturated
fat?
Recently, an editorial by Harvard's Walter Willett, M.D. in the
American Journal of Public Health (1990) acknowledged that even
though
"the focus of dietary recommendations is usually
a reduction of saturated fat intake, no relation between saturated fat
intake and risk of CHD was observed in the most informative prospective
study to date."
Another editorial, this time by Framingham's William P. Castelli
in the Archives of Internal Medicine (1992), declared for the
record that
"...in Framingham, Mass, the more saturated fat one ate, the
more cholesterol one ate, the more calories one ate, the lower
the person's serum cholesterol... the opposite of what the equations
provided by Hegsted at al (1965) and Keys et al (1957) would predict..."
Castelli further admitted that
"...In Framingham, for example, we found that the people who
ate the most cholesterol, ate the most saturated fat, ate the most calories,
weighed the least, and were the most physically active."
III. COCONUT OIL AND THE DIET/HEART HYPOTHESIS
For the past several decades you have heard about animal and human studies
feeding coconut oil that purportedly showed increased indices for cardiovascular
risk. Blackburn et al (1988) have reviewed the published literature of
coconut oil's effect on serum cholesterol and atherogenesis and have
concluded that when ...[coconut oil is] fed physiologically with other
fats or adequately supplemented with linoleic acid, coconut oil is a neutral
fat in terms of atherogenicity. After reviewing this same literature,
Kurup and Rajmohan (1995) conducted a study on 64 volunteers and found
...no statistically significant alteration in the serum total cholesterol,
HDL cholesterol, LDL cholesterol, HDL cholesterol/total cholesterol ratio
and LDL cholesterol/HDL cholesterol ratio of triglycerides from the baseline
values... A beneficial effect of adding the coconut kernel to the
diet was noted by these researchers.
How did coconut oil get such a negative reputation?
The question then is, how did coconut oil get such a negative reputation?
The answer quite simply is, initially, the significance of those changes
that occurred during animal feeding studies were misunderstood. The wrong
interpretation was then repeated until ultimately the misinformation and
disinformation took on a life of its own.
The problems for coconut oil started four decades ago when researchers
fed animals hydrogenated coconut oil that was purposefully altered to
make it completely devoid of any essential fatty acids. The hydrogenated
coconut oil was selected instead of hydrogenated cottonseed, corn or soybean
oil because it was a soft enough fat for blending into diets due to the
presence of the lower melting medium chain saturated fatty acids. The
same functionality could not be obtained from the cottonseed, corn or
soybean oils if they were made totally saturated, since all their fatty
acids were long chain and high melting and could not be easily blended
nor were they as readily digestible.
The animals fed the hydrogenated coconut oil (as the only fat source)
naturally became essential fatty acid deficient; their serum cholesterol
levels increased. Diets that cause an essential fatty acid deficiency
always produce an increase in serum cholesterol levels as well as an increase
in the atherosclerotic indices. The same effect has also been seen when
other essential fatty acid deficient, highly hydrogenated oils such as
cottonseed, soybean, or corn oils have been fed; so it is clearly a function
of the hydrogenated product, either because the oil is essential fatty
acid (EFA) deficient or because of trans fatty acids (TFA).
What about the studies where animals were fed with unprocessed coconut
oil?
Hostmark et al (1980) compared the effects of diets containing 10% coconut
fat and 10% sunflower oil on lipoprotein distribution in male Wistar rats.
Coconut oil feeding produced significantly lower levels (p=<0.05) of
pre-beta lipoproteins (VLDL) and significantly higher (p=<0.01) alpha-lipoproteins
(HDL) relative to sunflower oil feeding.
Awad (1981) compared the effects of diets containing 14% coconut oil,
14% safflower oil or a 5% "control" (mostly soybean) oil on
accumulation of cholesterol in tissues in male Wistar rats. The synthetic
diets had 2% added corn oil with a total fat of 16% Total tissue cholesterol
accumulation for animals on the safflower diet was six times greater than
for animals fed the coconut oil, and twice that of the animals fed the
control oil.
A conclusion that can be drawn from some of this animal research is
that feeding hydrogenated coconut oil devoid of essential fatty acids
(EFA) in a diet otherwise devoid of EFA leads to EFA deficiency and potentiates
the formation of atherosclerosis markers. It is of note that animals fed
regular coconut oil have less cholesterol deposited in their livers and
other parts of their bodies.
What about the studies where coconut oil is part of the normal diet
of human beings?
Kaunitz and Dayrit (1992) have reviewed some of the epidemiological
and experimental data regarding coconut-eating groups and noted that the
available population studies show that dietary coconut oil does not
lead to high serum cholesterol nor to high coronary heart disease mortality
or morbidity. They noted that in 1989 Mendis et al reported undesirable
lipid changes when young adult Sri Lankan males were changed from their
normal diets by the substitution of corn oil for their customary coconut
oil. Although the total serum cholesterol decreased 18.7% from 179.6 to
146.0 mg/dl and the LDL cholesterol decreased 23.8% from 131.6 to 100.3
mg/dl, the HDL cholesterol decreased 41.4% from 43.4 to 25.4 mg/dl (putting
the HDL values below the acceptable lower limit) and the LDL/HDL ratio
increased 30% from 3.0 to 3.9. These latter two changes would be considered
quite undesirable. As noted above, Kurup and Rajmohan (1995) studied the
addition of coconut oil alone to previously mixed fat diets and report
no significant difference.
Previously, Prior et al (1981) had shown that islanders with high intake
of coconut oil showed no evidence of the high saturated fat intake
having a harmful effect in these populations. When these groups migrated
to New Zealand however, and lowered their intake of coconut oil, their
total cholesterol and LDL cholesterol increased, and their HDL cholesterol
decreased.
What about the studies where coconut oil was deliberately fed to human
beings?
Some of the studies reported thirty and more years ago should have
cleared coconut oil of any implication in the development of coronary
heart disease (CHD).
For example, when Frantz and Carey (1961) fed an additional 810 kcal/day
fat supplement for a whole month to males with high normal serum cholesterol
levels, there was no significant difference from the original levels even
though the fat supplement was hydrogenated coconut oil.
Halden and Lieb (1961) also showed similar results in a group of hyperchole-sterolemics
when coconut oil was included in their diets. Original serum cholesterol
levels were reported as 170 to 370 mg/dl. Straight coconut oil produced
a range from 170 to 270 mg/dl. Coconut oil combined with 5% sunflower
oil and 5% olive oil produced a range of 140 to 240 mg/dl.
Earlier, Hashim and colleagues (1959) had shown quite clearly that feeding
a fat supplement to hypercholesterolemics, where half of the supplement
(21% of energy) was coconut oil (and the other half was safflower oil),
resulted in significant reductions in total serum cholesterol. The reductions
averaged -29% and ranged from -6.8 to -41.2%.
And even earlier, Ahrens and colleagues (1957) had shown that adding
coconut oil to the diet of hypercholesterolemics lowers serum cholesterol
from, e.g., 450 mg/dl to 367 mg/dl. This is hardly a cholesterol-raising
effect.
Bierenbaum et al (1967) followed 100 young men with documented myocardial
infarction for 5 years on diets with fat restricted to 28% of energy.
There was no significant difference between the two different fat mixtures
(50/50 corn and safflower oils or 50/50 coconut and peanut oils), which
were fed as half of the total fat allowance; both diets reduced serum
cholesterol. This study clearly showed that 7% of energy as coconut oil
was as beneficial to the 50 men who consumed it as for the 50 men who
consumed 7% of energy as other oils such as corn oil or safflower. Both
groups fared better than the untreated controls.
More recently, Sundram et al (1994) fed whole foods diets to healthy
normo-cholesterolemic males, where approximately 30% of energy was fat.
Lauric acid (C12:0) and myristic acid (C14:0) from coconut oil supplied
approximately 5% of energy. Relative to the baseline measurements of the
subjects prior to the experimental diet, this lauric and myristic acid-rich
diet showed an increase in total serum cholesterol from 166.7 to 170.0
mg/dl (+1.9%), a decrease in low density lipoprotein cholesterol (LDL-C)
from 105.2 to 104.4 mg/dl (-0.1%), an increase in high density lipoprotein
cholesterol (HDL-C) from 42.9 to 45.6 mg/dl (+6.3%). There was a 2.4%
decrease in the LDL-C/HDL-C ratio from 2.45 to 2.39. These findings indicate
a favorable alteration in serum lipoprotein balance was achieved when
coconut oil was included in a whole food diet at 5% of energy.
Tholstrup et al (1994) report similar results with whole foods diets
high in lauric and myristic acids from palm kernel oil. The HDL cholesterol
levels increased significantly from baseline values (37.5 to 46.0 mg/dl,
P<0.01) and the LDL-C/HDL-C ratios decreased from 3.08 to 2.69. The
increase in total cholesterol was from 154.7 (baseline) to 170.9 mg/dl
on the experimental diet.
Ng et al (1991) fed 75% of the fat ration as coconut oil (24% of energy)
to 83 adult normocholesterolemics (61 males and 22 females). Relative
to baseline values, the highest values on the experimental diet for total
cholesterol was increased 17% (169.6 to 198.4 mg/dl), HDL cholesterol
was increased 21.4% (44.3 to 53.8 mg/dl), and the LDL-C/HDL-C ratio was
decreased 3.6% (2.51 to 2.42).
When unprocessed coconut oil is added to an otherwise normal diet, there
is frequently no change in the serum cholesterol although some studies
have shown a decrease in total cholesterol. For example, when Ginsberg
et al provided an "Average American" diet with 2-3 times more
myristic acid (C14:0), 4.5 times more lauric acid (C12:0), and 1.2 times
more palmitic and stearic acid (C16:0 and C18:0) than their "Mono[unsaturated]"
diet and the National Cholesterol Education Program "Step 1"
diet, there was no increase in serum cholesterol, and in fact, serum cholesterol
levels for this diet group fell approximately 3% from 177.1 mg% to 171.8
mg% during the 22 week feeding trial.
It appears from many of the research reports that the effect coconut
oil has on serum cholesterol is the opposite in individuals with low serum
cholesterol values and those with high serum values. We see that there
may be a raising of serum total cholesterol, LDL cholesterol and especially
HDL cholesterol in individuals with low serum cholesterol. On the other
hand there is lowering of total cholesterol and LDL cholesterol in hypercholesterolemics
as noted above.
Studies that supposedly showed a hypercholesterolemic effect
of coconut oil feeding, in fact, usually only showed that coconut oil
was not as effective at lowering the serum cholesterol as was the more
unsaturated fat being compared. This appears to be in part because coconut
oil does not drive cholesterol into the tissues as does the more
polyunsaturated fats. The chemical analysis of the atheroma shows that
the fatty acids from the cholesterol esters are 74% unsaturated (41% is
polyunsaturated) and only 24% are saturated. None of the saturated fatty
acids were reported to be lauric acid or myristic acid (Felton et al 1994).
Should coconut oil be used to prevent coronary heart disease?
There is another aspect to the coronary heart disease picture. This
is related to the initiation of the atheromas that are reported to be
blocking arteries. Recent research is suggestive that there is a causative
role for the herpes virus and cytomegalovirus in the initial formation
of atherosclerotic plaques and the recloging of arteries after angioplasty.
(New York Times 1991) What is so interesting is that the herpes
virus and cytomegalovirus are both inhibited by the antimicrobial lipid
monolaurin; but monolaurin is not formed in the body unless there is a
source of lauric acid in the diet. Thus, ironically enough, one could
consider the recommendations to avoid coconut and other lauric oils as
contributing to the increased incidence of coronary heart disease.
Perhaps more important than any effect of coconut oil on serum cholesterol
is the additional effect of coconut oil on the disease fighting capability
of the animal or person consuming the coconut oil.
IV. COCONUT OIL AND CANCER
Lim-Sylianco (1987) has reviewed 50 years of literature showing anticarcinogenic
effects from dietary coconut oil. These animal studies show quite clearly
the nonpromotional effect of feeding coconut oil.
In a study by Reddy et al (1984) straight coconut oil was more inhibitory
than MCT oil to induction of colon tumors by azoxymethane. Chemically
induced adenocarcinomas differed 10-fold between corn oil (32%) and coconut
oil (3%) in the colon. Both olive oil and coconut oil developed the low
levels (3%) of the adenocarcinomas in the colon, but in the small intestine
animals fed coconut oil did not develop any tumors while 7% of animals
fed olive oil did.
Studies by Cohen et al (1986) showed that the nonpromotional effects
of coconut oil were also seen in chemically induced breast cancer. In
this model, the slight elevation of serum cholesterol in the animals fed
coconut oil was protective as the animals fed the more polyunsaturated
oil had reduced serum cholesterol and more tumors. The authors noted that
"...an overall inverse trend was observed between total serum lipids
and tumor incidence for the 4 [high fat] groups."
This is an area that needs to be pursued.
V. COCONUT OIL ANTIMICROBIAL BENEFITS
I would now like to review for you some of the rationale for the use
of coconut oil as a food that will serve as the raw material to provide
potentially useful levels of antimicrobial activity in the individual.
The lauric acid in coconut oil is used by the body to make the same
disease-fighting fatty acid derivative monolaurin that babies make from
the lauric acid they get from their mothers= milk. The monoglyceride monolaurin
is the substance that keeps infants from getting viral or bacterial or
protozoal infections. Until just recently, this important benefit has
been largely overlooked by the medical and nutrition community.
Recognition of the antimicrobial activity of the monoglyceride of lauric
acid (monolaurin) has been reported since 1966. The seminal work can be
credited to Jon Kabara. This early research was directed at the virucidal
effects because of possible problems related to food preservation. Some
of the early work by Hierholzer and Kabara (1982) that showed virucidal
effects of monolaurin on enveloped RNA and DNA viruses was done in conjunction
with the Center for Disease Control of the US Public Health Service with
selected prototypes or recognized representative strains of enveloped
human viruses. The envelope of these viruses is a lipid membrane.
Kabara (1978) and others have reported that certain fatty acids (e.g.,
medium-chain saturates) and their derivatives (e.g., monoglycerides) can
have adverse effects on various microorganisms: those microorganisms that
are inactivated include bacteria, yeast, fungi, and enveloped viruses.
The medium-chain saturated fatty acids and their derivatives act by
disrupting the lipid membranes of the organisms (Isaacs and Thormar 1991)
(Isaacs et al 1992). In particular, enveloped viruses are inactivated
in both human and bovine milk by added fatty acids (FAs) and monoglycerides
(MGs) (Isaacs et al 1991) as well as by endogenous FAs and MGs (Isaacs
et al 1986, 1990, 1991, 1992; Thormar et al 1987).
All three monoesters of lauric acid are shown to be active antimicrobials,
i.e., alpha-, alpha'-, and beta-MG. Additionally, it is reported that
the antimicrobial effects of the FAs and MGs are additive and total concentration
is critical for inactivating viruses (Isaacs and Thormar 1990).
The properties that determine the anti-infective action of lipids are
related to their structure; e.g., monoglycerides, free fatty acids. The
monoglycerides are active, diglycerides and triglycerides are inactive.
Of the saturated fatty acids, lauric acid has greater antiviral activity
than either caprylic acid (C-10) or myristic acid (C-14).
The action attributed to monolaurin is that of solubilizing the lipids
and phospholipids in the envelope of the virus causing the disintegration
of the virus envelope. In effect, it is reported that the fatty acids
and monoglycerides produce their killing/inactivating effect by lysing
the (lipid bilayer) plasma membrane. However, there is evidence from recent
studies that one antimicrobial effect is related to its interference with
signal transduction (Projan et al 1994).
Some of the viruses inactivated by these lipids, in addition to HIV,
are the measles virus, herpes simplex virus-1 (HSV-1), vesicular stomatitis
virus (VSV), visna virus, and cytomegalovirus (CMV). Many of the pathogenic
organisms reported to be inactivated by these antimicrobial lipids are
those known to be responsible for opportunistic infections in HIV-positive
individuals. For example, concurrent infection with cytomegalovirus is
recognized as a serious complication for HIV+ individuals (Macallan et
al 1993). Thus, it would appear to be important to investigate the practical
aspects and the potential benefit of an adjunct nutritional support regimen
for HIV-infected individuals, which will utilize those dietary fats that
are sources of known anti-viral, anti-microbial, and anti-protozoal monoglycerides
and fatty acids such as monolaurin and its precursor lauric acid.
No one in the mainstream nutrition community seems to have recognized
the added potential of antimicrobial lipids in the treatment of HIV-infected
or AIDS patients. These antimicrobial fatty acids and their derivatives
are essentially non-toxic to man; they are produced in vivo by humans
when they ingest those commonly available foods that contain adequate
levels of medium-chain fatty acids such as lauric acid. According to the
published research, lauric acid is one of the best "inactivating"
fatty acids, and its monoglyceride is even more effective than the fatty
acid alone (Kabara 1978, Sands et al 1978, Fletcher et al 1985, Kabara
1985).
The lipid coated (envelop) viruses are dependent on host lipids for
their lipid constituents. The variability of fatty acids in the foods
of individuals accounts for the variability of fatty acids in the virus
envelop and also explains the variability of glycoprotein expression.
Loss of lauric acid from the American diet
Increasingly, over the past 40 years, the American diet has undergone
major changes. Many of these changes involve changes of fats and oils.
There has been an increasing supply of the partially hydrogenated trans-containing
vegetable oils and a decreasing amount of the lauric acid-containing oils.
As a result, there has been an increased consumption of trans
fatty acids and linoleic acid and a decrease in the consumption of lauric
acid. This type of change in diet has an effect on the fatty acids the
body has available for metabolic activities.
VI. LAURIC ACID IN FOODS
The coconut producing countries
Whole coconut as well as extracted coconut oil has been a mainstay in
the food supply in many countries in parts of Asia and the Pacific Rim
throughout the centuries. Recently though, there has been some replacement
of coconut oil by other seed oils. This is unfortunate since the benefits
gained from consuming an adequate amount of coconut oil are being lost.
Based on the per capita intake of coconut oil in 1985 as reported by
Kaunitz (1992), the per capita daily intake of lauric acid can be approximated.
For those major producing countries such as the Philippines, Indonesia,
and Sri Lanka, and consuming countries such as Singapore, the daily intakes
of lauric acid were approximately 7.3 grams (Philippines), 4.9 grams (Sri
Lanka), 4.7 grams (Indonesia), and 2.8 grams (Singapore). In India, intake
of lauric acid from coconut oil in the coconut growing areas (e.g., Kerala)
range from about 12 to 20 grams per day (Eraly 1995), whereas the average
for the rest of the country is less than half a gram. An average high
of approximately 68 grams of lauric acid is calculated from the coconut
oil intake previously reported by Prior et al (1981) for the Tokelau Islands.
Other coconut producing countries may also have intakes of lauric acid
in the same range.
The US experience
In the United States today, there is very little lauric acid in most
of the foods. During the early part of the 20th Century and up until the
late 1950s many people consumed heavy cream and high fat milk. These foods
could have provided approximately 3 grams of lauric acid per day to many
individuals. In addition, desiccated coconut was a popular food in homemade
cakes, pies and cookies, as well as in commercial baked goods, and 1-2
tablespoons of desiccated coconut would have supplied 1-2 grams of lauric
acid. Those foods made with the coconut oil based shortenings would have
provided additional amounts.
Until two years ago, some of the commercially sold popcorn, at least
in movie theaters, had coconut oil as the oil. This means that for those
people lucky enough to consume this type of popcorn the possible lauric
acid intake was 6 grams or more in a three (3) cup order.
Some infant formulas (but not all) have been good sources of lauric
acid for infants. However, in the past 3-4 years there has been reformulation
with a loss of a portion of coconut oil in these formulas, and a subsequent
lowering of the lauric acid levels.
Only one US manufactured enteral formula contains lauric acid (e.g.,
Impact7); this is normally used in hospitals for tube feeding; it is reported
to be very effective in reversing severe weight loss in AIDS patients,
but it is discontinued when the patients leave the hospital because it
is not sufficiently palatable for oral use. The more widely promoted enteral
formulas (e.g., Ensure7, Nutren7) are not made with lauric oils, and,
in fact, many are made with partially hydrogenated oils.
There are currently some candies sold in the US that are made with palm
kernel oil, and a few specialty candies made with coconut oil and desiccated
coconut. These can supply small amounts of lauric acid.
Cookies such as macaroons, if made with desiccated coconut, are good
sources of lauric acid, supplying as much as 6 grams of lauric acid per
macaroon (Red Mill). However, these cookies make up a small portion of
the cookie market. Most cookies in the United States are no longer made
with coconut oil shortenings; however, there was a time when many US cookies
(e.g., Pepperidge Farm) were about 25% lauric acid.
Originally, one of the largest manufacturers of cream soups used coconut
oil in the formulations. Many popular cracker manufacturers also used
coconut oil as a spray coating. These products supplied a small amount
of lauric acid on a daily basis for some people.
How much lauric acid is needed?
It is not known exactly how much food made with lauric oils is needed
in order to have a protective level of lauric acid in the diet. Infants
probably consume between 0.3 and 1 gram per kilogram of body weight if
they are fed human milk or an enriched infant formula that contains coconut
oil. This amount appears to have always been protective. Adults could
probably benefit from the consumption of 10 to 20 grams of lauric acid
per day. Growing children probably need about the same amounts as adults.
VII. RECOMMENDATIONS
The coconut oil industry needs to make the case for lauric acid now.
It should not wait for the rapeseed industry to promote the argument for
including lauric acid because of the increased demand for laurate. In
fact lauric acid may prove to be a conditionally essential saturated fatty
acid, and the research to establish this fact around the world needs to
be vigorously promoted.
Although private sectors need to fight for their commodity through the
offices of their trade associations, the various governments of coconut
producing countries need to put pressure on WHO, FAO, and UNDP to recognizes
the health importance of coconut oil and the other coconut products. Moreover,
those representatives who are going to do the persuading need to believe
that their message is scientifically correct -- because it is.
Among the critical foods and nutrition "buzz words" for the
21st Century is the term "functional foods." Clearly coconut
oil fits the designation of a very important functional food.
About the Author
Mary G. Enig, PhD is the author of Know Your Fats: The Complete Primer
for Understanding the Nutrition of Fats, Oils, and Cholesterol, Bethesda
Press, May 2000.
The book is available at
Amazon>
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