*Plant-based oils processed at high temperatures are unhealthy, researchers find
Nigerian scientists have condemned the recent attack by the Western world on local plant-based oils, which have been used over the centuries in Africa to boost nutrition and improve wellbeing.
They said the initial negative recommendation on the nutritional value of coconut oil was based on faulty scientific evidence and propaganda to promote the use of non-tropical oils from industrialised countries such as corn oil and cottonseed oil against local options like coconut oil, palm oil, groundnut oil and many others.
The scientists said nutritional experts in the United States and Canada still caution against the use of coconut oil because of the abundance of saturated fatty acids in the oil and the potential risk of high cholesterol and its health risks.
They, however, are unanimous that plant-based oils processed at very high temperatures including coconut oil could be harmful to health even as they recommend Virgin Coconut Oil (VCO) for optimal health.
Also, researchers at Nnamdi Azikiwe University Awka, Anambra State, and the Anambra University are currently conducting clinical trials on VCO-based Syferol, which is used for managing for peptic ulcers. Syferol contains VCO and other herbs.
According to Food as Medicine: Functional Food Plants of Africa, VCO is unprocessed oil obtained from fresh coconut endocarp. It contains medium-chain fatty acids that are assimilated more easily by the body than the long-chain fatty acids found in many other cooking oils. It has become a major dietary supplement with many beneficial properties.
But the American Heart Association (AHA) had on Monday said that coconut oil is just as unhealthy as beef fat and butter because it is predominantly a saturated fat.
Saturated fat, which is known for raising Low Density Lipo-protein (LDL) that is “bad” cholesterol, is commonly linked to animal fats, but it is also found in tropical plant oils like palm and coconut.
According to the AHA, 82 per cent of coconut oil is saturated fat, compared to only 63 per cent in butter, 50 per cent in beef fat and only 39 per cent in pork lard. The only oil that ranked worse than coconut oil was palm kernel oil, which is one of the most widely consumed vegetable oils on the planet.
Lead author of the AHA report, Dr. Frank Sacks, said: “We want to set the record straight on why well-conducted scientific research overwhelmingly supports limiting saturated fat in the diet to prevent diseases of the heart and blood vessels,” said “Saturated fat increases LDL – bad cholesterol – which is a major cause of artery-clogging plaque and cardiovascular disease.”
The debate on saturated fats has been going on for years. “In the real world, ‘all good’ vs. ‘all bad’ is reliably more about salesmanship than data,” Dr. David L. Katz wrote in a piece for HuffPost back in 2011.
However, Sacks seems to agree with Katz, suggesting Americans limit but not eliminate saturated fats from their diets. “A healthy diet doesn’t just limit certain unfavourable nutrients, such as saturated fats, that can increase the risk of heart attacks, strokes and other blood vessel diseases. It should also focus on healthy foods rich in nutrients that can help reduce disease risk, like poly- and mono-unsaturated vegetable oils, nuts, fruits, vegetables, whole grains, fish and others,” he said in a news release.
According to a study published in Trends in Food Science & Technology, it has been established that coconut oil is considered a saturated fat because it contains more than 90 per cent of saturated fatty acids. Epidemiologic study suggests that the consumption of high amounts of saturated fat and cholesterol leads to high blood cholesterol. Due to that, coconut oil has received bad reputation. However, in the past few years, clinical studies have been conducted on coconut oil and VC and positive outcomes were obtained which might refute those arguments.
The study published in Trends in Food Science & Technology, is titled “Virgin coconut oil: emerging functional food oil. The researchers from the University of Putra, Malaysia, noted that coconut oil is rich in medium chain triacylglycerol (MCT). Extensive review has been made on MCT. Having rich in MCT, consumption of coconut oil is associated with increase in the serum triacylglycerol but incorporation of structured lipid and other functional substances may improve the lipid profile. A study conducted on regular coconut consumers of Polynesian populations, revealed that consumption of coconut was not associated with heart attacks and other forms of cardiovascular disease. Coconut oil is also rich in lauric acid, a fatty acid with strong antimicrobial property, which inhibited various pathogenic bacteria such as Listeria monocytogenes. There was also a study showing protective effect of coconut oil together with menhaden oil in reducing mammary tumour incidence in animal study.
The effects of consumption of VCO on various lipid parameters have been conducted. The findings indicated that triglycerides in serum and tissues were significantly lower in VCO-treated animals compared to copra oil and control animals. High-density lipoprotein (HDL) that is “good” cholesterol in VCO fed animals was increased while LDL that is “bad” cholesterol level were significantly decreased compared to copra oil. Polyphenol fraction of VCO was found to be more beneficial than polyphenol fractions of copra and groundnut oils in preventing the copper-induced oxidation of LDL as indicated by the low thiobarbituric acid reactive substance (TBARS) and reduced carbonyl formation.
According to Food as Medicine: Functional Food Plants of Africa, the most abundant fatty acid in coconut, lauric acid, possesses several biological activities. Lauric acid is known to have antiviral, antibacterial, and antiprotozoal qualities. It is converted to the monoglyceride monolaurin in the human or animal body. Monolaurin itself is antiviral, antibacterial, and antiprotozoal.
Available publications indicate that monolaurin is capable of destroying lipid-coated viruses such as Human Immuno-deficiency Virus (HIV), herpes, cytomegalovirus, influenza, various pathological bacteria, including Listeria monocytogenes and Helicobacter pylori, and protozoa such as Giardia lamblia and Plasmodium falciparum. It is believed that the compound is synthesized in babies from the lauric acid of mother’s milk. Caprylic acid, another fatty acid found in coconut, also has antimicrobial activities. Reports also suggest that coconut oil is useful as an antioxidant, antihypertensive, and antidiabetic functional food. The fatty acids can be used for the production of biodiesel through an enzymatic conversion process.
Advocates of the VCO as a dietary supplement claim the following health benefits: immune modulation, diabetes, high blood pressure, cancer, hair care, skin care, stress relief, maintaining cholesterol levels, weight loss, bone strength, proper digestion and metabolism, heart diseases, dental care, HIV, and relief from kidney problems. It is believed that these health benefits of VCO can be attributed to the presence of the medium-chain fatty acids and phenolic compounds, with their known properties such as antimicrobial, antioxidant, antifungal, antibacterial, and anti-inflammatory properties.
A locally produced coconut oil, prepared by cold press, the IHP-Virgin Coconut Oil tagged ‘Drugstore in a Bottle,’ is making progress. The formulator who is also the author of the book, Food as Medicine: Functional Food Plants of Africa, Prof. Maurice Iwu, told The Guardian: “There is no unanimity regarding the health benefits of coconut oil. Although coconut oil is a saturated fat, studies have found that eating virgin coconut oil does not have adverse effects upon the heart. On the contrary, it appears to reduce the risk of high cholesterol and heart attack.
“VCO should not be confused with refined coconut oil produced from dried copra or so called partially hydrogenated coconut oil. Unlike refined coconut oil, which is produced through dry method from copra.”
Iwu who is also a professor of pharmacognosy, and Chief Executive Officer (CEO) of Bioresources Development Group (BDG) and Interceed Health Products (IHP), added: “VCO is produced through wet method, via coconut milk. There are many methods available for the production of coconut oil, so the source of the VCO for optimum health benefits is very important. It contains medium-chain fatty acids, which are much easier on the body than the long chain fatty acids found in many other cooking oils.
“VCO also contains some phenolic acids such as protocatechuic, vanillic, caffeic, syringic, ferulic and p-coumaric acids. The studies suggest that the antioxidant activity and other health benefits of VCO could be due partly to these phenolic compounds.”
Also, contrary to views propagated by the Western media that palm oil is not good for health, scientists have found that locally produced palm oil is better than imported vegetable oils, very rich in nutrients and has more vitamin A than carrots. In fact, palm oil has been shown to be the richest source of tocotrienol- a super antioxidant proven to reverse heart disease and fight cancer. However, palm oil is beneficial only when cooked or boiled not fried. Frying palm oil has been shown to produce dangerous chemicals that may lead to organ damage.
Meanwhile, a research published in 2015 found that coconut oil could help prevent the formation of plague and development of gum disease. The ancient Indian technique of swishing coconut oil around the mouth is a growing health trend. There has been little scientific evidence to show the benefits of oil pulling.
A study published in April 2015 found the ancient Indian practice using coconut oil in the mouth could be an effective procedure in decreasing plaque formation and plaque-induced gum disease.
The research, published in the Nigerian Journal of Medicine’s March/April 2015 edition, looked at 60 people between the ages of 16 and 18 who added oil pulling to their oral hygiene routine over a 30-day period. Their plaque and gum disease levels were assessed on days 1, 7, 15, and 30.
After just seven days of oil pulling, levels of plaque and gum disease significantly reduced, and continued to decrease over a period of a month. The researchers, from Kennur Dental College in India, said: “Coconut oil is an easily available edible oil.
“It is unique because it contains predominantly medium chain fatty acids, of which 45-50 percent is lauric acid. Lauric acid has proven anti inflammatory and antimicrobial effects.”
In Nigeria, the juice of the young spadix of coconut, Cocos nucifera (Arecaceae) is traditionally used for the treatment of diarrhea, diabetes and other ailments. Meanwhile, the Malaysian researchers in the subsequent study determined the antioxidant status of rats fed VCO. The results indicated that the activities of catalase (CAT), and superoxide dismutase (SOD), which were mutually supportive team of defense against reactive oxygen species (ROS) and pre- venting lipid peroxidation, were increased in VCO. The lipid peroxide levels were significantly less in the heart, liver and kidney of VCO fed animals compared to the other oil fed groups. Compared to groundnut and copra oils, VCO feeding was found to increase the total glutationine (GTN) content, a sensitive indicator of antioxidant status. The study concluded that consumption VCO was superior in antioxidant property than coconut oil extracted by dry process.
The researchers also investigated the influence of VCO on blood coagulation factors, lipid levels and LDL oxidation in cholesterol fed Sprague-Dawley rats. The lipid levels and thrombotic risk factors as indicated by platelets, fibrin and fibrinogen levels were lower in rats fed VCO compared to copra oil and comparable to sunflower oil. The antioxidant vitamin levels were found to be higher in VCO fed animals compared to the other groups. The LDL isolated from VCO fed animals when subjected to oxidant in vitro, showed significant resistance to oxidation as compared to LDL isolated from the copra and groundnut oils.
The Malaysian researchers concluded: “Since its first appearance, VCO has gained wide attraction among the public and scientific community as functional food oil. From the health point of view, VCO has been documented as having more beneficial effects in clinical trials such as having more antioxidant potential compared to refined coconut oil. The underlying justification was based on the fact that VCO did not undergo the RBD process, which destroys some of the biologically active components such as phenolic compounds. A number of studies confirmed the higher content of phenolic contents, which correlated with higher antioxidant activity in VCO, compared with refined coconut oil. Investigators in developing methods for detection of adulteration in VCO also addressed attention. The overall knowledge improvement allowed the identification of suitable new techniques to better differentiate VCO from other vegetable oils, especially from refined coconut oil.”