Natural health bloggers, alternative medicine providers, and even Dr. Oz having been cuckoo for coconut oil in recent years. Coconut water and milk have gone mainstream as well, stocked even at your local Stop and Go, but I’ll focus on oil for this post. I bought a tub of it, (it is solid like Crisco at room temperature) and was pretty excited about using it. It has a great flavor and consistency for baking, popcorn and sautéing. But perhaps it is one of those “too good to be true” situations? I took a closer look.
There are over 1,000 scientific articles about dietary use of coconut oil. Coconut oil is a rare plant source of saturated fat, usually found in animal products, such as meat, poultry, and dairy. It is known to increase LDL (“bad” cholesterol.) LDL levels correlate with risk factors for our leading killer, heart disease. But many report coconut oil as a healthy saturated fat. It contains antioxidants as well.
Dr. Jay Kenney, a PhD nutrition scientist at the Pritikin Longevity Center in Miami, Florida is concerned about calling coconut oil healthy. He says it’s easy to get confused about oils, so he shares these facts:
All oils are a mix of mono-unsaturated, poly-unsaturated and saturated fatty acids. The type of fatty acid that makes up most of the particular oil becomes its defining label. Saturated fat has the highest artery-clogging ability, and is therefore deemed less desirable. Coconut oil is 92% saturated fat, even higher than butter (64%) and lard (40%).
There are different kinds of saturated fatty acids. Some are long-chain, having 12 or more carbon atoms, while medium-chain fats have fewer than 12. These various fats have different effects on the body, in particular LDL levels. For example, long-chained stearic acid found in chocolate has little impact on LDL, even though it is 60% saturated fat.
Coconut oil is mostly lauric acid, and at a length of 12 carbons, it is at the junction between medium- and long-chain fatty acids. Dr. Michael Greger, a Cornell physician who runs the informative site www.NutritionFacts.org, is also concerned about portraying coconut oil as a superfood. He took a critical look at many studies and found data lacking to support a health benefit.
For example, studies of people on traditional Polynesian diets with high levels of tropical oils like coconut have found that they have relatively low rates from heart disease despite high LDL cholesterol levels. But there are other issues at play, since their diet is very high in dietary fiber and heart-healthy omega-3 fatty acids from fish. Most were non-smokers, and were physically very active. So it’s hard to separate out what health benefits can be attributed to coconut oil.
On a positive note, a meta-analysis of 60 studies published in 2003 by the American Journal of Clinical Nutrition showed that lauric acid increased total cholesterol, but much of its effect was on HDL (“good”) cholesterol, so oils rich in lauric acid decreased the ratio of total to HDL cholesterol, which is healthy.
You may recall your doctor talking to you about your cholesterol ratios, in addition to information about good, bad and total cholesterol. Other long-chained saturated fats called palmitic and myristic raised LDL cholesterol and had little effect on the ratio. Stearic acid, mentioned above regarding chocolate, reduced the ratio slightly.
One other research paper I found interesting and potentially promising was published in the British Journal of Nutrition in 2011. This found that coconut oil caused less of a post-meal inflammatory response than other types of saturated fat. As we realize the profound effect that inflammation has on us, in particular regarding heart disease, this bears further study.
Coconut oil’s unusual ability to boost HDL may make it “less bad” than the high saturated fat content and LDL effects might indicate. A decreased inflammatory response might also be part of the coconut oil magic. Dr. Walter Willet of the Harvard School of Public Health suggests using it sparingly for now and says “it’s still probably not the best choice among the available oils (such as olive oil) to reduce the risk of heart disease.” It’s another one of those situations… we need further study.