032: Is Coconut Oil Killing Us?
Mastering Nutrition Episode 32
In this episode, I weigh in on the American Heart Association’s new Presidential Advisory and Dietary Fats and Cardiovascular Disease, and all the headlines that have been spinning on the supposed risks of coconut oil.
In this episode, you will find all of the following and more.
0:00:53 The recent headlines on coconut oil.
0:01:50 The American Heart Association’s new Presidential Advisory, “Dietary Fats and Cardiovascular Disease” is not centrally about coconut oil, but it laments the popularity of coconut oil.
0:04:06 This is a position paper reinforcing the conventional view about saturated fat as the stance against it within the scientific community has begun to soften around the edges. The 2015 dietary guidelines and the 2016 Ramsden paper reflect that softening.
0:11:37 The inclusion and exclusion criteria of the “4 core trials” of the AHA meta-analysis.
0:13:36 The 4 core trials.
0:13:58 The Finnish Mental Hospitals Study makes the largest contribution to the AHA conclusion but was not a randomized controlled trial and doesn’t belong in this list.
0:20:42 The Oslo Diet-Heart Study was included and made a contribution, yet other trials were excluded on the basis of confounding that were far less confounded than Oslo.
0:24:37 The LA Veterans Administration Hospital Study showed that a vitamin E-deficient diet makes you vulnerable to the heart disease-promoting effects of smoking, and that vegetable oils cause more cancer than cigarettes.
0:33:38 The Medical Research Council study showed a trend toward a benefit of soybean oil that was not statistically significant. Lack of heat damage to the fats in the diet, coenzyme Q10, and omega-6/omega-3 balance could have played a role in the trend.
0:38:08 Exclusion of Rose 1965 and Minnesota Coronary Survey from the “4 core trials” was fair.
0:39:32 Controversy over the possible contribution of trans fats to the results of the Sydney Diet Heart Study. But this as a basis for exclusion could have excluded the LA Veterans Administration Hospital Study as well.
0:44:57 The impact of including or excluding MRC and Sydney shows how the conclusions are driven not by the cumulative data but on the qualitative decisions about which studies to include.
0:49:01 The observational studies are hopelessly confounded by popular campaigns about the heart-healthiness of replacing saturated fat with polyunsaturated fat.
0:53:00 The experiments in monkeys using lard, palm oil, and dietary cholesterol to bring their plasma cholesterol to 300-400 mg/dL.
0:55:30 The oxidation of lipoproteins drives atherosclerosis and polyunsaturated fats drive the oxidation. This is embraced by the leading conventional thinkers.
1:02:59 The AHA position on coconut oil is based on its effect on LDL-C, explicitly arguing in favor of ignoring its effects on HDL-C, and explicitly acknowledging the complete absence of clinical evidence.
1:10:10 Coconut oil has benefits unrelated to heart disease, such as the antimicrobial (antifungal and antibacterial) effects of lauric, capric, and caprylic acids, and the increased energy expenditure and decreased appetite caused by capric and caprylic acids.
1:13:58 Coconut oil could protect against heart disease due to its low polyunsaturated fat content.
1:16:29 Traditional Pacific island diets were far higher in saturated fat than the standard American diet, yet heart disease was absent.
1:19:07 The Tokelau Migrant Study showed that the freedom from heart disease on Tokelau, where coconut consumption pushed saturated fat over 50% of calories, was not due to genetics or age.
Links and Research Related to “Is Coconut Oil Killing Us?”
The American Heart Association Presidential Advisory, “Dietary Fats and Cardiovascular Disease”
As the Cholesterol Consensus Crumbles, the Stance on Saturated Fat Softens (blog post, podcast)
The Scientific Report of the 2015 Dietary Guidelines Committee
The eighth edition of the actual Dietary Guidelines
The 2010 Mozaffarian meta-analysis
The 2016 Ramsden paper
Ramsden’s criticism of the Finnish Mental Hospitals Study
My discussion of the Finnish Mental Hospitals Study in How to Read a Science Paper
Controversy over trans fat contribution to Sydney Diet-Heart results
Coenzyme Q10 protects against PUFA-induced aging in rodents.
Daniel Steinberg’s Cholesterol Wars
Good Fats, Bad Fats: Separating Fact From Fiction
AJCN Publishes a New PUFA Study That Should Make us Long For the Old Dayscovers many of the trials discussed herein.
The effect of dietary fat on the total-to-HDL-cholesterol ratio
Absence of heart disease on Kitava, where coconut is the main source of fat.
Absence of heart disease in Pukapuka and Tokelau, where coconut consumption was even higher.
Stephan Guyenet’s series on the Tokelau Migrant Study
MCT oil increases energy expenditure.
Masterclass With Masterjohn: Oxidative Stress and Heart Disease
Masterclass With Masterjohn: Vegetable Oils and Heart Disease, Examining the Controversy
Episode 30: What to Do About High Cholesterol
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