If you've read some of my posts lately on the subject of climate "science," you may have come to the conclusion that there is some kind of highly unusual mass hysteria going on there. It seems that people have convinced themselves that the subject of anthropogenic climate change is really important, even existential. We must "save the planet"! This is something way too important to let the sideline quibbles of some congenital deniers get in the way of the moral crusade to rescue earth and humanity. Along the way, the multitudes have managed to lose track of the question of whether the available empirical evidence supports or refutes the hypothesis at hand -- in other words, they have lost track of the "science."
But is this situation really unique, or even unusual? Or are there other prominent examples in "science" of groupthink getting up such a huge momentum, and of so many livelihoods and careers becoming dependent on a prevailing paradigm, that it becomes impossible for any amount of adverse evidence to stop the train?
Our friends at Maggie's Farm remind us of another big example, with a post yesterday titled "Dietary fat and settled science." The main subject is what is known as the diet-heart hypothesis, that is, the idea that a high fat diet causes heart disease. Excerpt:
The low saturated fat craze was triggered by a 1950 study by Ancel Keys, a study which is now generally accepted as fraudulent. It spurred many further studies over the years but, as yet, there is no proven causal relationship between dietary fat and cardiovascular disease. In fact, there are very high saturated fat cultures (Eskimos, Masai) with very low cardiovascular disease rates.
Does your cholesterol level matter? Other than in familial hypercholesterolemia, probably not. So why check them on your every-3 year physical exams? Medical advice is conservative, slow to change, and fearful of being wrong so too-often adopts the precautionary principle. Thus when articles like this one comes out: Popular belief that saturated fat clogs up arteries is a myth, experts say, there is always pushback like "Don't tell people that, they'll get confused."
All the links there are eminently worth following. But, as the text indicates, the third of them raises an additional question -- one perhaps even more important than that of a link between diet and heart disease -- which is the question of whether cholesterol in the blood is an important causative factor in heart disease. Even if a high fat diet is ruled out as a causative factor in heart disease, it could still be possible that high cholesterol in the blood -- brought on by factors other than a high fat diet -- could be the driving factor in heart disease. And remember, it is cholesterol in the blood, measured at your periodic check-up at your doctor's office, that is going to end you up with a prescription for one of those "statin" pills, once a day for life, if your "numbers" are not in some officially-determined appropriate range. This article at PRWeb puts the annual U.S./Europe/Japan statin market at $12+ billion. And about 15 million Americans take the daily dose.
Following that third Maggie's Farm link, via an intermediate step, will take you to an editorial just a couple of days ago in something called the British Sports Medicine Journal, by Aveem Malhotra and other authors, titled "Saturated fat does not clog the arteries: coronary heart disease is a chronic inflammatory condition, the risk of which can be effectively reduced from healthy lifestyle interventions." This article directly discusses the state of the evidence as to whether high cholesterol in the blood is really a causative factor for heart disease. Excerpt:
Decades of emphasis on the primacy of lowering plasma cholesterol, as if this was an end in itself and driving a market of ‘proven to lower cholesterol’ and ‘low-fat’ foods and medications, has been misguided. Selective reporting may partly explain this misconception. Reanalysis of unpublished data from the Sydney Diet Heart Study and the Minnesota coronary experiment reveal replacing saturated fat with linoleic acid containing vegetable oils increased mortality risk despite significant reductions in LDL and total cholesterol (TC).
And then there's this, of particular interest to those, like yours truly, who find themselves over the age of 60:
And in those over 60 years, a recent systematic review concluded that LDL cholesterol is not associated with cardiovascular disease and is inversely associated with all-cause mortality.8
LDL cholesterol is "not associated with cardiovascular disease"? It "is inversely associated with all-cause mortality"? What?????? Following that footnote 8 will take you to a 2016 article by Uve Ravnskov and others in the British Medical Journal titled "Lack of an association or an inverse association between low-density-lipoprotein cholesterol and mortality in the elderly: a systematic review." To be fair, Ravnskov has long been known as a doubter of the cholesterol/heart disease hypothesis. The study is a review of substantial amounts of literature. Here is the conclusion:
Our review provides the first comprehensive analysis of the literature about the association between LDL-C and mortality in the elderly. [Wait -- Am I "elderly"?] Since the main goal of prevention of disease is prolongation of life, all-cause mortality is the most important outcome, and is also the most easily defined outcome and least subject to bias. The cholesterol hypothesis predicts that LDL-C will be associated with increased all-cause and CV mortality. Our review has shown either a lack of an association or an inverse association between LDL-C and both all-cause and CV mortality. The cholesterol hypothesis seems to be in conflict with most of Bradford Hill’s criteria for causation, because of its lack of consistency, biological gradient and coherence.
Needless to say, the Malhotra editorial has produced some push back from the usual establishment figures (what Dr. Joy Bliss at MF characterizes as "Don't tell people that, they'll get confused.") If you are interested in reading a sampling, here is a roundup from The Guardian. Here's my comment: If cholesterol in the blood really were the key causative factor in heart disease, you would see a strong positive relationship between the two in every study, and a strong beneficial effect from anything that succeeded in lowering the cholesterol. These relationships are not there. But way too many people have their lives invested in this theory for the train to be stopped any time soon.