How is that a discredited diet developed by a man with no scientific or nutritional background and with no legitimate scientific studies supporting it has been endorsed by Medicare to be taught intensively to patients after their coronary bypass surgery or heart attack?
The explanation involves pseudoscience, evangelical nutritional fervor and a Senator who managed to get Congress to pass laws supporting “integrative” medicine
Nathan Pritikin’s Pseudoscience Longevity Legacy
Nathan Pritikin was an “inventor” who became convinced that heart disease could be treated by following an ultra-low fat diet.
After establishing his “Longevity Center” in Santa Monica for well-heeled clients, (the average price per week for one is about $4,500) he wrote a book entitled “The Pritikin Program for Diet and Exercise” in 1979.
The book sold more than 10 million copies in paperback and hardcover and was on the New York Times Bestseller Top Ten list for more than 54 weeks.
He committed suicide in 1985 at the age of 69 years
The Pritikin brand, however, lives on and continues to promote a diet that contradicts scientific findings in the last two decades that clearly indicate an ultra-low fat diet is not sustainable or effective in reducing heart disease.
There are two aspects of the Pritikin brand that make it stand out from the rest of the fad diets that clutter the book store shelves and the internet blogs: a thin veneer of scientific legitimacy and funding by the federal government.
The Pritikin Brand Has Done A Very Good Job Of Promoting Itself As Evidence-Based But It Is Not
From the very slick website promoting the Pritikin Longevity Centers:
“More than 100 studies in prestigious medical journals like the New England Journal of Medicine and Circulation have documented the Pritikin Program’s extraordinary success in helping thousands worldwide. Discover what the Pritikin Program can do for you.Whether severe restriction of dietary fat is a realistic public health approach to lowering serum cholesterol levels is uncertain.”
Although partially true, this is a totally misleading statement.
The reference from the “prestigious” New England Journal of Medicine is a letter to the editor (thus not peer-reviewed research) written by R. James Barnard, Ph.D in 1990.
Barnard has a Ph. D in exercise physiology and has worked as a consultant for the Pritikin center since 1978. As an employee of Pritikin he cannot be expected to provide unbiased scientific analyses.
He has written a book (Understanding Common Diseases and the Value of the Pritikin Eating and Exercise Program) which was published by the Pritikin organization in 2013.
In the preface to this book, he indicates “It wasn’t long after I started to work with the Pritikin participants that I realized Mr. Pritikin’s claims were correct…at this point I decided to collect data for publication in the medical literature”
Good science involves generating a hypothesis and then performing experiments to prove or disprove the hypothesis. In Barnard’s case he clearly had decided beforehand that the diet worked and he spent the rest of his career trying to gather data from the humans in the Pritikin center (60 studies) and from rodents that he fed high sugar and fat diets (40 studies) to support this claim.
Barnard does have a publication in Circulation (as opposed to a letter) but it is also an example of bad science and would not be published in a reputable journal in this day and age. His Circulation publication in 2002 looks at what happens in 11 men who are given an ultra low-fat diet and forced to exercise aerobically for 45-60 minutes daily.
They were forbidden to consume alcohol, cigarettes or caffeine.
There was no control group for comparison and we have no idea what the lifestyle of the men was before entering the study. And, of course, the investigators were not blinded and were extremely biased.
What a surprise! The men lost weight, had a lower blood pressure and a lower cholesterol level after 3 weeks of being tortured on the Pritikin diet and exercise plan.
Barnard’s other publications, which serve as the sole “evidence base” for the Pritikin program are similar to the Circulation publication: they involve short, unblinded, uncontrolled studies of what happens to various metabolic parameters when individuals are subject to the Pritikin torture program.
Interestingly, by 1990 when he wrote that letter to the editor he ended it by saying:
“Whether severe restriction of dietary fat is a realistic public health approach to lowering serum cholesterol levels is uncertain”
What’s Wrong with the Pritikin Diet?
The Pritikin diet is similar to other now discredited diets promulgated by Dean Ornish and Caldwell Esselstyn which are ultra-low fat and almost vegan. Such ultra-low fat diets are not recommended by any major scientific organization and are not supported by the scientific literature.
Pritikin’s diet recommends you never consume what they term “saturated-rich foods” such as
- butter
- tropical oils like coconut oil
- fatty meats
- dairy foods like cheese, cream and whole/low fat milk
- Processed meat such as hot dogs, bacon and bologna
- cholesterol-rich foods like egg yolks
This diet eliminates what most of us would consider a satisfying and filling meal.
The Pritikin diet recommends “caution” (less is better) for the following:
- oils
- sugar
- salt
- refined grains
The most recent scientific evidence on diet strongly contradicts a substantial number of these recommendations: for example, dietary cholesterol is not of concern: fish and vegetable oil, particularly olive oil, consumption is encouraged, dairy fat reduces atherosclerosis and obesity.
Medicare Covers Pritikin for “Intensive Cardiac Rehabilitation”
As part of the Affordable Care Act, Congress established and funded something called “intensive cardiac rehabilitation” or ICR.
The portion of the act that establishes ICR was crafted because of the influence of the legendary ultra low-fat/vegetarian evangelist Dean Ornish upon Senator Tom Harkin of Iowa.
Harkin has been waging a war on science and promoting pseudoscience and “alternative” medicine for some time. As science-based medicine wrote:
“Senator Tom Harkin (D-IA) helped set up the National Center on Complementary and Alternative Medicine (NCCAM). The whole idea of setting up such an agency is a bit quixotic—after all, the National Institutes of Health already study health science. As my colleagues and I have written many times before, the very idea of the agency seems ridiculous. Many, many studies have been funded which fail basic tests of plausibility and ethical propriety. Also, a huge percentage of the studies funded fail to ever publish their results. Still, some studies have been published, and more often than not, they find that the “alternative” modality being studied fails to behave better than placebo. That’s probably the sole redeeming quality of the agency, but not enough to keep it open, as these studies could have been done under the auspices of the NIH.”
The wording of the ICR section says that an approved ICR program is a physician-supervised program that
has shown, in peer-reviewed published research, that it accomplished—one or more of the following:
positively affected the progression of coronary heart disease; or reduced the need for coronary bypass surgery; or
reduced the need for percutaneous coronary interventions; and a statistically significant reduction in 5 or more of the following measures from their level before receipt of cardiac rehabilitation services to their level after receipt of such services: low density lipoprotein;triglycerides;body mass index;systolic blood pressurediastolic blood pressure and the need for cholesterol, blood pressure, and diabetes medications.
These criteria are clearly crafted to correspond to the weak data that Barnard had published during his time working for and promoting the Pritikin Longevity Center.
The Decision Memo that CMS delivered approving the Pritikin program is embarrassingly naive in its analysis:
The study by Barnard and colleagues (1983) showed that participation in the Pritikin Program was associated with a reduction in the need for bypass surgery. Although the sample size was small, the study provided long term follow-up. At five years, there were four deaths (6%). There was no direct comparison group but the authors reported that, at the time (1976-1977), mortality associated with coronary artery disease was “as high as 50% by the third year.” At five years 12 patients (19%) had bypass surgery. Since all patients were recommended to have bypass surgery prior to enrollment, there was a reduction in bypass surgery over the follow-up period.
The 1983 “study” by Barnard is really not even worthy of publication. He was collecting information on 60 participants in the Pritikin program who had been told by their physicians that they needed coronary bypass surgery.
We have no idea what would have happened to these highly motivated, cherry-picked individuals if they had not entered the Pritikin program. Comparison to historical controls to support the efficacy of an intervention is unacceptable in today’s scientific literature.
Intensive Cardiac Rehabilitation: Good Idea But Bad Implementation
I am a huge supporter of working with patients who have coronary artery disease or are at risk of heart attack to reduce their risk by lifestyle change and appropriate medications.
I applaud science-based government initiatives to study this and implement proven techniques.
Unfortunately, the way that ICR was foisted on Americans shows how easily good ideas can be hijacked by a few fervent hucksters who have the ears of prominent politicians who lack the background to properly understand science-based medicine.
Skeptically Yours,
-ACP