It wasn't even Throwback Thursday, but the American Heart Association (AHA) recently issued a new Presidential Advisory on saturated fats, assuring us all that they do indeed cause heart disease. Newspaper headlines ran with it, and all my patients asked me, "Have I truly been causing heart disease with my___________?" (In my house, that would be eggs, bacon, coconut oil, cheese, and cream. What about your house?)
My short answer was "Don't worry: they had a deadline so they took an old Advisory from 1961 and just changed the date. Stay the course!"
My long answer would point to the billions of dollars spent on research since that time, with a plea to look at some slightly more discriminating interpretations of the data.
The AHA essentially accepts as a given that high LDL (so-called bad cholesterol) values are not only associated with but cause heart disease, that dietary saturated fats raise LDL levels, so—duh—saturated fats also cause heart disease. There are so many problems with their presumption (it has always been a presumption, waiting and waiting for a good proof) that it's hard to know where to start.
I could point out that saturated fats also raise HDL (you like that one: it's "good" cholesterol!) and even more than LDL, such that the net effect is either neutral or a benefit. What about that? I could point to recent work by Dave Feldman at cholesterolcode.com: as a curious and fascinating engineer, he has a fair amount of individuals' data in which three days of a high fat diet lowered their worrisome cholesterol numbers. What about that?
But again there is a much longer and convincing answer that attempts to answer both the error in AHA thinking and the more important question: just what does cause heart disease? We are surviving heart disease better than we did 50 years ago, and rates looked to be declining commensurate with our decreased smoking habit. Erase that decline, however, because heart disease rates are again on the rise, matching our increasing problems with obesity, hypertension, type 2 diabetes and fatty liver disease.
The original AHA warnings were not based on solid science. The only kind of science that is sufficiently rigorous to serve as a basis for heath advice is a clinical trial where folks are tested before and after different interventions. Over the last decades, tens of thousands of Americans have been tested on diets rich in either saturated fats or vegetable oils. The results have been buried, discounted, or downright discarded. (Legitimate spy novel stuff: uncovering decades old data in a dusty box, stored away in a private home.)
While the AHA claims a 30% risk reduction by switching to margarine (who are these people?), their methodology was suspect. Bottom line: when you look at heart attacks, strokes and related deaths: no difference at all. When a study made that clear, the AHA found a reason to discard the study. ("It's only one year, we want two, and we want them now.")
Now I will grant you that swapping out fats and carting in the oils will lower your cholesterol.
Cholesterol forms the basis for all your sex hormones, and is a key component to healthy tissues throughout your body, especially in your brain where cholesterol and fat comprise over 60% of the weight of a healthy brain.
Cholesterol and the heart? It's possible that cholesterol is the "first aid" that your body sends to damaged areas in the heart. A hefty proportion of folks with heart attacks have normal cholesterol values (about one-third), and many people with high cholesterol have never and will never had a heart attack. A recent drug trial was suspended mid-stream because although it miraculously lowered bad cholesterol and even boosted good cholesterol: there was no change in heart disease-related outcomes. No reduction in heart attack, stroke, or death.
We have obeyed the AHA over the last 50 years, marked reduced our intake of saturated fat and increased our consumption of vegetable oils, both intentional (heart-healthy oil purchases) and unintentional (in almost every kind of prepared food.) The results have not been promising: our heart disease rates, along with the rates of other modern diseases, are making us a very sick group of people, with a life expectancy that declined last year, for the first time since 1993. Rising fatalities from heart disease most of all, but also stroke, diabetes, as well as drug overdoses and accidents, should motivate us all to ask the question: what are we doing wrong?
The largest single increase was deaths related to Alzheimer's disease, and it turns out (amazing!) that a proper lifestyle to prevent heart disease can also prevent and even reverse Alzheimer's disease.
The research on diet and heart disease has been consistent: none of the major reviews over the last two to three decades has found any evidence that saturated fat has any effect at all on mortality, from heart disease or all causes. Despite the steady drum roll of one study after another dispelling that erroneous connection, the AHA and our US national dietary guidelines continue to suggest we limit saturated fats to 10% of daily calories, at a maximum. Even lower if you have high cholesterol!
In one AHA discounted study, the Minnesota Coronary Experiment (1968-1943), the men who successfully lowered their cholesterol with AHA dietary recommendations: were even more likely to die from a heart attack. Specifically: there was a 22% higher risk of death for each 30 point reduction in serum cholesterol. Doesn't that make it malpractice to lower someone's cholesterol? (Although concluded decades ago, the data has been literally abandoned and only thoroughly studied in the last few years.)
If you are curious for a thorough discussion of the uneven-handedness of the AHA, you might enjoy the defense of saturated fats on Medscape written by Nina Teicholz and Dr. Eric Thorn, "Saturated Fats and CVD: AHA Convicts, We Say Acquit."
I would say that the one area in which all opinions converge, is that the combination of high sugar and high fat is likely a deadly duo. From my reading, I believe that it's the sugar that causes the problem, not the fat. In the absence of high sugar, the fat is not deadly.
I will continue to enjoy butter, steak, eggs, and coconut oil, but will have to stop shaking my head in disbelief long enough to do that!