Editor’s note: This post is a collaborative effort between Grant Ritchey, a Science-Based Medicine semi-regular, and Stephanie Tornberg-Belanger, a co-author of the research paper discussed below and who brought the study to Grant’s attention. We are pleased to welcome Stephanie as a guest contributor to SBM.
That amazing coconut oil! What can’t it do?
In his last SBM post, Grant reported on a systematic review of the literature that undermined just about everything dentists had been taught in dental school and have been preaching to patients since The Olden Times: flossing, as it turns out, is not the be-all, end-all that we’ve been led to believe with regard to cavity and gum disease prevention. While the message itself was interesting and relevant, the meta-message in that piece is that we all must be willing to slay our own sacred cows when the evidence demands it, even if it requires shedding long-held, cherished beliefs. This is difficult for any human being to do, and skeptics who are presumably open minded are no different (and can sometimes be worse, because we are often overconfidently convinced of our “rightness”).
So with that in mind, gather ’round children, because we have another meta-message for you. This one deals with coconut oil.
(Pause for gasps.) (more…)
In a former life, when I was an Air Force doctor, one of my duties was to give “Healthy Heart” briefings with a script furnished by Air Force experts. It covered the scientific consensus of the time (the early 80s) about diet. It recommended a low fat diet, restricted cholesterol and saturated fat, and demonized tropical oils like palm oil and coconut oil. (Trans fats weren’t yet on the agenda.)
Times have changed. Today we are more lenient about cholesterol in the diet, less concerned about total fat and saturated fat, and more concerned about trans fats. While many major health organizations still discourage its use, coconut oil has not only been rehabilitated in the public mind, but all kinds of health benefits are being claimed for it.
The fats in coconut oil
Coconut oil is high in saturated fats; it contains more saturated fatty acids than any other non-hydrogenated oil. It is stable and has a long shelf life. It is used in movie theaters to pop popcorn and in South Asian cuisine for dishes like curries. A hydrogenated version of coconut oil is an ingredient in non-dairy creamers. Much of the research done on coconut oil studied hydrogenated or partially hydrogenated forms. According to an article in the New York Times:
Partial hydrogenation creates dreaded trans fats. It also destroys many of the good essential fatty acids, antioxidants and other positive components present in virgin coconut oil. And while it’s true that most of the fats in virgin coconut oil are saturated, opinions are changing on whether saturated fats are the arterial villains they were made out to be. “I think we in the nutrition field are beginning to say that saturated fats are not so bad, and the evidence that said they were is not so strong,” Dr. Brenna said.
Coconut oil contains lauric acid, which raises both HDL and LDL cholesterol levels. This may improve the cholesterol profile, although there are concerns that it may promote atherosclerosis by other means. Virgin coconut oil contains medium-chain triglycerides, which are not as risky as some other saturated fats.