Thanks to the suggested cardiovascular benefits of coconut oil, it has become a highly sought-after source of fat. But is it really good for the heart?
Flipping through magazines and walking down supermarket aisles nowadays, it is not uncommon to see coconut oil* being touted as a healthy oil because of its numerous health benefits particularly for cardiovascular health. Coconut oil has long been avoided as it is high in saturated fat, commonly associated with an increased risk of high cholesterol and cardiovascular disease (CVD). This is rightly so as coconut fat contains about 90% saturated fat; the highest compared to any fat source.
You now have two sources of conflicting information, unsure of what to believe because on the one hand, it is a proven fact that there is a causal relationship between saturated fat and CVD and on the other hand, certain research has demonstrated that coconut oil consumption has some properties good for the heart. What should we believe and who should we trust?
First, let us look at the fat in coconut oil, what can increase the risk of CVD, and the research related to this much-debated fat.
*The terms oil and fat are used interchangeably. There is no difference in the chemical composition of oil and fat; only its state at room temperature (20-25 Degree Celsius).
Fat composition in coconut oil comprises 90% saturated fat and 10% unsaturated fat. Pound for pound, coconut oil contains the most saturated fat as compared to butter (64%), talon (40%) and lard (40%). What differentiates the saturated fat in coconut oil from the other sources is the length of its fatty acid chain.
Medium chain saturated fatty acids (MCTs), which are metabolised by the liver for energy almost instantly, are the predominant fatty acids in coconut oil and this is what makes coconut oil ‘better’ than other saturated fatty acid sources such as butter. Unlike their animal counterparts, these MCTs in coconut oil are quickly metabolised for energy with a small proportion of it stored.
High density lipoproteins (HDL) and low density lipoproteins (LDL) are commonly measured to assess an individual’s risk of CVD. Simply put, higher levels of HDL (better known as ‘good cholesterol’) indicate a lower risk of CVD. However a high level of LDL (‘bad cholesterol’) would indicate otherwise. Hence, when assessing a food’s cholesterol, apart from absolute levels of HDL and LDL, we have to take into account the HDL/LDL ratio as well.
Many studies that have been conducted and published in scientific journals* have shown that while coconut oil consumption raises HDL levels significantly, it also raises levels of LDL and cholesterol. The latter two, when raised, also raises one’s risk of CVD. However, many of these studies tend to be short term and are largely focused on its effect on lipids (HDL, LDL and cholesterol) rather than heart disease. On top of this, some of them are done with the Polynesian population such as Pukapuka, Tokelau and Kitava, where coconut is a dietary staple.
Proponents of coconut oil tend to argue that the Polynesian population, which consumes a large amount of their energy from coconut fat (21%-63%), have a low incidence of CVD despite the increase in LDL and cholesterol amongst this population, albeit insignificant, and this applies to the general population as well.
These findings, however, can hardly be extrapolated to the Singapore population because very simply, we live extremely different lifestyles from the Polynesians. In a more developed society like ours, we consume more processed foods, exercise less and consume less fibre whereas Polynesians derive most of their proteins from fresh fish, fresh fruit and vegetables and lead a relatively active lifestyle. In addition, their fat sources came from coconut flesh, milk and cream which may have protective properties such as antioxidants, fibre and minerals as compared to processed, refined coconut oil which we find on our local supermarket shelves.
*Published in the European Journal of Clinical Nutrition ("Effects Of Dietary Coconut Oil, Butter And Safflower Oil On Plasma Lipids, Lipoproteins And Lathosterol Levels" conducted in 1998), European Journal of Lipid Research ("Independent Effects Of Dietary Saturated Fat And Cholesterol On Plasma Lipids, Lipoproteins, And Apolipoproteins" in 1983), British Journal of Nutrition ("The Effect Of Daily Consumption Of Coconut Fat And Soya-Bean Fat On Plasma Lipids And Lipoproteins Of Young Normolipidaemic Men" in 1990), American Journal of Clinical Nutrition (“Cholesterol, coconuts, and diet on Polynesian atolls: a natural experiment: the Pukapuka and Tokelau island studies” conducted in 1981 and “Do Not Alter Postprandial Or Fasting Plasma Homocysteine And Inflammatory Markers In Healthy Malaysian Adults” in 2011), amongst others
If you’re seeking to reduce your CVD risks, the more effective alternative would be to replace your saturated fat with the heart-healthy, unsaturated variety. In several studies comparing coconut oil to vegetable oil, individuals fed coconut oil showed significantly elevated cholesterol levels in all trials. Although reports on coconut oil’s effect in HDL levels and HDL: LDL ratio has proven rather inconsistent and inconclusive. In contrast, the LDL-reducing effect of unsaturated fat has been well documented. This very fact is important because, according to a study by the Cholesterol Treatment Trialist Collaboration (an international organization that specializes in the study of cholesterol) in 2010, ‘every 1-mmol/L reduction in LDL corresponds to an average 22% reduction in CVD mortality and morbidity’. Simply put, replacing your saturated fat with unsaturated fat could be good for your heart!
Inevitably, we do crave the aroma and taste of coconut which is totally acceptable but this is where we choose our battles! For example, we could replace butter with coconut oil in baked goods as they have relatively similar functional properties. Subsequently, we could replace coconut oil with coconut milk, the latter containing less saturated fat, in certain dishes where possible too. Therefore there is no reason to avoid coconut oil; we just have to consume it in moderation.