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Coconut Oil
Commonly occurring unsaturated fatty acids are linoleic acid (in ground nut oil) and linolenic acid (sun flower oil). Thus people started to take these vegetable oils with reduced usage of coconut oil. Within the last 50 years, per capita consumption of coconut oil in Kerala has been reduced to one-third. Interestingly, during the same period in the same population, the incidence of myocardial infarction has increased to three folds. This fact alone is enough to disprove the anti-propaganda against coconut oil.
It may be stressed that all saturated fats are not harmful. Now we know that saturated fatty acids in coconut oil are of the medium chain variety. Nearly 55 % of the fatty acids in coconut oil are lauric acid (12 carbon atoms) and 20% myristic acid (14 carbon atoms), both medium chain fatty acids. On the other hand, the fats that cause heart disease are saturated long chain fatty acids with 16 or 18 carbon atoms in their structure.
Coconut oil is the most easily digestible and absorbed class of fats and does not circulate in the blood stream and is not deposited.
Atherosclerosis
Coronary artery disease (CAD) is a complex degenerative disease that causes reduced or absent blood flow in one or more of the arteries that encircle the heart. Atherosclerosis is the principal cause of CAD and is the single largest killer of both men and women all over the world. The most deadly presentation of CAD is acute myocardial infarction (AMI).
Risk factors of atherosclerosis
A number of large epidemiological studies have identified that an increase in serum cholesterol level is associated with increased risk of death from heart disease. For every 10% lowering of cholesterol, CAD mortality was reduced by 13%. In healthy persons, cholesterol level varies from 150 to 200 mg/dl. If other risk factors are present, cholesterol level should be kept preferably below 180 mg/dl. Values around 220 mg/dl will have moderate risk and values above 240 mg/dl need treatment.
Blood levels of LDL cholesterol (bad cholesterol) should be kept under 130 mg/dl. Levels between 130 and 159 mg/dl are borderline; while above 160 mg/dl carry definite risk. HDL cholesterol (good cholesterol) levels above 60 mg/dl protect against heart disease. A level below 40 mg/dl increases the risk of CAD. For every 1 mg/dl drop in HDL, the risk of heart disease rises 3%. If the ratio of total cholesterol / HDL is more than 3.5, it is dangerous. Similarly, LDL : HDL ratio more than 2.5 is also detrimental.
Hypertension is an important risk factor for the development of atherosclerosis, atherosclerotic cardiovascular disease and stroke. Diabetes mellitus is commonly associated with hyperlipidemia, hypertension, abnormalities of coagulation, platelet adhesion, atherosclerosis and myocardial infarction.
Coconut oil does not produce atherosclerosis
There are dozens of animal and human studies to disprove allegations about coconut oil enhancing the risk of a CAD. There is not even one paper in the whole literature directly showing that coconut oil increases cardiac diseases. In fact, coconut oil is neutral with respect to atherogenicity (plaque formation).
Coconut oil and body weight
Being overweight increases the risk for osteoarthritis, diabetes, heart disease, stroke and early death. Overweight person taking coconut oil, containing medium chain fatty acids, gradually over the months lose weight effortlessly (Geliebter 1980; Baba 1982; Bach and Babayan 1982).
The idea is that when you take fat, you will gain weight. In this context, it may be a paradoxical finding that overweight persons taking coconut oil are losing weight. The explanation is the following: Long chain fats will almost always go into fat stores; this will eventually make the person overweight and will cause dyslipidemia. However, as explained previously, the medium chain fatty acids will be immediately utilized for energy purposes, and will not be deposited in the body. Since coconut oil will speed up metabolism and the body will actually be burning more calories in a day, this will help to reduce weight (Hill et al 1989).
Lipid profile in coconut oil consumers with disease
At Amrita Institute of Medical Sciences, Kochi ,lipid profile was analysed in 76 coronary artery disease patients, out of which 41 were used to take coconut oil and 35 were used to take sunflower oil. There was no statistically significant difference in the cholesterol, HDL or LDL levels in coconut oil consuming patients versus sunflower oil consuming patients. Plasma fatty acid composition reflected no changes with dietary fat source.
Coconut oil and lipid Oxidative stress
Free radicals generated by oxidative stress are the cause for many chronic diseases such as coronary artery disease, ageing process etc. At Amrita Institute of Medical Sciences, the effect of diets containing coconut oil or sunflower oil on oxidative stress and lipid peroxidation was studied in rabbits maintained for 6 months. Serum lipid values did not show significant variation between animals fed coconut oil or sunflower oil Lipid peroxidation was found to be higher in sunflower oil fed rabbits, compared to controls or coconut oil fed rabbits. Coconut oil intake did not cause hyper cholesterolemia or oxidative stress in rabbits (Sabitha et al, 2010).
Fatty acid composition of atheromatous plaques
In another study conducted at Amrita Institute of Medical Sciences, 71 samples of plaques (from diseased coronary arteries) were analysed. Out of these patients, 48 persons were using coconut oil and 23 persons were using sunflower oil routinely. Fatty acids were extracted by chloroform and then anlysed by HPLC (high performance liquid chromatography). Surprisingly, the fatty acid content of the plaque did not show any difference between coconut oil consumers versus sunflower oil consumers. In both coconut oil consumers and sunflower oil consumers, the major substances present in the plaques were saturated fatty acids; palmitic acid (46%) and stearic acid (33%) of total lipids. The concentrations of unsaturated fatty acids and medium chain fatty acids were low. Lauric acid (fatty acid present in coconut oil) was only 3.5% of the total content of plaques in both coconut oil consumers and sunflower oil consumers.
Summary
The general advice given by physicians against the use of coconut oil needs re-evaluation. This mis-information arose, when long chain saturated fatty acids (LCSFA) were shown to increase cholesterol level. Since coconut oil also contains saturated fatty acids, people equated them with LCSFA. Now it is known that coconut oil contains medium chain fatty acids (MCFA). Metabolisms of LCFA and MCFA are drastically different. Coconut oil, within normal limits, neither decrease nor increase cholesterol levels. The advantages of coconut oil are that it does not affect serum cholesterol (neutral); it produces very little free radicals, as opposed to other oils (beneficial); it is rapidly absorbed, rapidly oxidized and is not deposited (beneficial) and it helps in resisting invading micro-organisms.