Tag Archives: Pritikin

Is Dean Ornish’s Lifestyle Program “Scientifically Proven To Undo (Reverse) Heart Disease?”

Supporters of vegetarian/ultra low fat diets like to claim that there is solid scientific evidence of the cardiovascular benefits of their chosen diets.

To buttress these claims they will cite the studies of Esseslystn, Pritikin and Ornish.

I’ve previously discussed the bad science underlying the programs of Esselsystn and Pritikin but have only briefly touched on the inadequacy of Dean Ornish’s studies.

The Ornish website proclaims that their program is the first program “scientifically proven to undo (reverse) heart disease.” That’s a huge claim. If it were true, wouldn’t the Dietary Guidelines for Americans, the American Heart Association, and most cardiologists and nutrition experts be recommending it?

Who Is Dean Ornish?

Dean Ornish has an MD degree from Baylor University and trained in internal medicine but has no formal cardiology or nutrition training (although many internet sites including Wikipedia describe him as a cardiologist.)

Ornish, according to the Encyclopedia of World Biographies became depressed and suicidal in college and underwent psychotherapy “but it was only when he met the man who had helped his older sister overcome her debilitating migraine headaches that his own outlook vastly improved. Under the watch of his new mentor, Swami Satchidananda, Ornish began yoga, meditation, and a vegetarian diet, and even spent time at the Swami’s Virginia center.”

Can Ornish’s Program Reverse Heart Disease?

After his medical training Ornish founded the Preventive Medicine Research Institute and has has widely promoted his Ornish Lifestyle Program.  the website of which claims:

Dr. Ornish’s Program for Reversing Heart Disease® is the first program scientifically proven to “undo” (reverse) heart disease by making comprehensive lifestyle changes.

The Ornish claims are based on a study he performed between 1986 and 1992 which originally had 28 patients with coronary artery disease in an experimental arm and 20 in a control group. You can read the details of the one year results here.and the five year results here.

There are  so many limitations to this study that the mind boggles that it was published in a reputable journal.

-Recruitment of patients. 

193 patients with significant coronary lesions from coronary angiography were “identified” but only 93 “remained eligible.” These were “randomly” assigned to the experimental or control groups. Somehow , this randomization process assigned 53 to the experimental group and 40 to the usual-care control group.

If this were truly a 1:1 randomization the numbers would be equal and the baseline characteristics equal.

Only 23 of the 53 assigned to the experimental group agreed to participate and only 20 of the control group.

The control group was older, less likely to be employed and less educated.

“The primary reason for refusal in the experimental group was not wanting to undergo intensive lifestyle changes and/or not wanting a second coronary angiogram; control patients refused primarily because they did not want to undergo a second angiogram.”

In other words, all of the slackers were weeded out of the experimental group and all of the patients who were intensely motivated to change their lifestyle were weeded out of the control group. Gee, I wonder which group will do better?

-The Intervention.

The experimental patients received “intensive lifestyle changes (<10% fat whole foods vegetarian diet, aerobic exercise, stress management training, smoking cessation, group psychosocial support).
The control group had none of the above.

Needless to say this was not blinded and the researchers definitely knew which patients were in which group.

Control-group patients were “not asked to make lifestyle changes, although they were free to do so.”

There is very little known about the 20 slackers in the control group. I can’t find basic information about them-crucial things like how many smoked or quit smoking or how many were on statin drugs.

-The Measurement

Progression or regression of coronary artery lesions was assessed in both groups by quantitative coronary angiography (QCA) at baseline and after about a year.

QCA as a test for assessing coronary artery disease has a number of limitations and as a result is no longer utilized for this purpose in clinical trials. When investigators  want to know if an intervention is improving CAD they use techniques such as intravascular ultraound or coronary CT angiography (see here) which allow measurement of total atherosclerotic plaque burden.

Rather than burden the reader  with the details at this point I’ve included a discussion of this as an addendum.

-The Outcome

Ornish has widely promoted  this heavily flawed study as showing “reversal of heart disease” because at one year the average percent coronary artery stenosis by angiogram had dropped from 40% to 37.8% in the intensive lifestyle group and increased from 42.7% to 46.1% in the control patients.

The minimal diameter (meaning the tightest stenosis) changed from 1.64 mm at baseline in the experimental to 1.65 at one year. At 5 years the minimal diameter had increased another whopping .001 mm to 1.651. 

 

 

In other words even if we overlook the huge methodologic flaws in the study the  so-called  “reversal” was minuscule.


Utlimately, dropping coronary artery blockages by <5 % doesn’t really matter unless that is also helping to prevent heart attacks or death or strokes or some outcome that really matters.

There were no significant differences between the groups at 5 years in hard events such as heart attack or death.
In fact 2 of the experimental group died versus 1 of the control group by 5 years.

There were less stents and bypasses performed in the Ornish group but the decision to proceed to stent or bypass is notoriously capricious when performed outside the setting of acute MI. The patients in the experimental group under the guidance of Ornish and their Ornish counselors would be strongly motivated to do everything possible to avoid intervention.

I’ve gotten a lot of flack for humorously suggesting that Nathan Pritikin killed himself as a result of the austere no fat diet he consumed but the bottom line on any lifestyle change is both quality and quantity of life.

If you are miserable most days due to your rigid diet you might consider that life is no longer worth living

Ornish’s Lifestyle Intervention Is Not A Trial Of Diet …And Other Points

 

Although often cited as justification of ultralow fat diet, the Ornish Lifestyle trial doesn’t test diet alone.

It is a trial of multiple different interventions with frequent counseling and meetings to reinforce and guide patients.

The interventions included things that we know are really important for long term health-regular exercise, smoking cessation, and weight management. These factors alone could account for any differences in the outcome but they are easily adopted without becoming a vegetarian.

The patients who agreed to the experimental arm were a clearly highly motivated bunch who agreed to this really strict regimen. Even in this population there was a 25% drop out rate.

Since investigators clearly knew who the “experimental patients” were and they were clearly interested in good outcomes in these patients there is a high possibility of bias in reporting outcomes and referring for interventions.

Despite all the limitations the study does raise an interesting hypothesis. Should we all be eating vegan diets?

 if Ornish really wanted to scientifically prove his approach he should have repeated it with much better methodology and much larger numbers.

Finally, this tiny study has never been reproduced at any other center.

Because of the small numbers, lack of true blinding, lack of hard outcomes and use of multiple modalities for lifestyle intervention, this study cannot be used to support the Ornish/Esselstyn/Pritikin dietary approach.

It most certainly doesn’t show that the Ornish Lifestyle Program “reverses heart disease.” Consequently, you will not find any evidence-based source of nutritional information or guideline (unless it has a vegan/vegetarian philosophy or is being funded by the Ornish/Pritikin lifestyle money-making machines) recommending these diets.

Skeptically Yours,

-ACP

N.B.1 A recent paper on noninvasive assessment of atherosclerotic plaque has a great infographic which shows how coronary artery disease progresses and how and when in the progression various imaging modalities are able to detect plaque:

I’ve inserted a vertical red arrow which shows how IVUS detects very early atheroma whereas angiography (ICA, green line) only detects later plaque when it has started protruding into the lumen of the artery.

The paper notes that “Intravascular ultrasound (IVUS)  constitutes the current gold standard for plaque quantification. Multiple studies using IVUS and other techniques have revealed a robust relation between statin therapy and plaque regression. In the ASTEROID trial coronary atheroma volume regressed by 6.8% during 24 months of high-intensity lipid therapy. A meta-analysis of IVUS trials including 7864 patients showed an association between plaque regression and decreased cardiovascular events.”

While I believe Ornish started off as a legitimate scientist several authors have pointed out that he has joined the ranks of pseudoscientific practiioners.

Here’s one analysis from Science Blogs :

In the end, the problem is that Dr. Ornish has yoked his science to advocates of pseudoscience, such as Deepak Chopra and Rustum Roy. Why he’s done this, I don’t know. The reason could be common philosophy. It could be expedience. It could be any number of things. By doing so, however, Dr. Ornish has made a Faustian deal with the devil that may give him short-term notoriety now but virtually guarantees serious problems with his ultimately being taken seriously scientifically, as he is tainted by this association. Let me yet again reemphasize that this relabeling of diet, exercise, and lifestyle as somehow being “alternative” is nothing more than a Trojan Horse. Inside the horse is a whole lot of woo, pseudoscience and quackery such as homepathy, reiki, Hoxsey therapy, acid-base pseudoscience, Hulda Clark’s “zapper,” and many others,

The Pritikin Diet: Discredited By Medicine But Now Endorsed By Your Federal Government!

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 CMS 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 has managed to get Congress to pass laws supporting “integrative” medicine

Nathan Pritikin’s Pseudoscience Longevity Legacy

Nathan Pritikin is an “inventor” who became convinced that heart disease could be treated by following an ultra-low fat diet.

Screen Shot 2015-11-29 at 9.22.28 AMAfter establishing his “Longevity Center” in Santa Monica for well-healed clients, (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 died at the age of 69 after slashing his wrists with a razor blade.

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.

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.

It’s a wonder they didn’t slit their wrists while trapped in the Pritikin center undergoing this program.

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 vegetarian. 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 most of what makes for a tasty 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.

 

 

 

Which Popular Diets Are Supported By Science?

Which of the currently popular and highly marketed diets are best for weight loss and cardiovascular health? Can science answer this question?
questI just took a 90 minute online “course” taught by Eric Rimm of the Harvard School of Public Health; I think he does a good job of summarizing the scientific evidence on this topic and presenting it in a way that the average layperson can understand.

You can sign up for free here. If you’re not interested in spending your time watching him, here are my take-home points:

1. When evaluating the efficacy of a diet to control weight, the best evidence comes from observational studies that involve tens of thousands patients over decades and/or (preferably) randomized control trials that last at least two years.

2. The Paleo, Wheat-belly, gluten-free, Atkins, South Beach, and Zone diets do not have good evidence supporting sustained weight loss or health benefits. In general, people who follow these diets will be consuming lots of fresh vegetables, nuts and “healthy” fats and avoiding processed food, which is good, and this likely explains any  benefits achieved.

3. Of all the diets, the low-fat diet (Ornish/Pritikin/China Study are the extreme examples of this) is the only one which has strong evidence showing an absence of benefit.

Yes, the diet that was recommended to Americans for 30 years does not help with weight loss in the long run for the vast majority of individuals.

As Rimm says “We need to eliminate the dogma that low fat is needed for weight loss.”

Dr. Rimm spends a good amount of time on this, highlighting findings from a study of 50 thousand women (the Women’s Health Initiative), which lasted for 9 years. In the first year, women on the low-fat diet (counseled to consume <20% of calories in the form of fat), lost more weight than those on the usual diet, however, in subsequent years they gained back the weight and did not differ from the higher fat consuming group.

There was also no difference in the rates of dying or contracting any disease between the two groups.

The problem with the low fat diet was adherence. Although a very small percentage of individuals can remain on a  vegan or really low-fat diet and successfully lose weight and be healthy, the majority of us can’t.

By the end of the study the low fat group had increased their fat consumption to 28% which was not much less than what the usual group was consuming (32%)

Over time, the low fat group gradually added fats because they taste better and they are more satiating.

4. The DASH diet has evidence showing improvement in blood pressure, and cholesterol. The heart of the DASH diet is an eating plan rich in fruits and vegetables, low-fat and nonfat dairy, along with nuts, beans, and seeds.

Unfortunately, it was developed in an era when all fats were considered bad and proof of cardiovascular benefit is lacking.

5. Mediterranean diet. Gets a strong pass from Rimm with multiple studies showing benefits in both weight reduction and reduction of cardiovascular mortality.

The Med diet also demonstrates good long term adherence because of its diversity and inclusion of fat (for taste and satiety).

Improved adherence has been shown to be the major determinant of diet success. When you add regular counseling and support to any diet it works better and can be sustained.

This is the Mediterranean diet I recommend:

1. Lots of fresh fruits and vegetables. These contain fiber, phytochemicals, minerals.

2. Two servings of fish per week.

3. Plenty of nuts (and drupes!), legumes, and seeds.

4. Grains are allowed, preferably all whole grains.

5. Moderate alcohol consumption (1 drink/day for women, 2 drinks/day for men).

6. Olive oil.

7. Meat is allowed.

8. Eggs and dairy are allowed.

Dr. Rimm is still clinging to the idea that all saturated fats should be limited and preferfat replacementably replaced by PUFAs or MUFAs. He presented this graphic (courtesy of Dr. Willet at Harvard), which illustrates the most prevalent concepts about saturated fat replacement.

Risk of heart disease is on the y axis. According to this graph, If you replace saturated fat with trans fat or sugar/refined starch, risk goes up.

If you replaced saturated fat with unsaturated vegetable fats or whole grains, risks go down.

Most nutritional experts now can agree on the importance of the key components of the Med diet and the lack of efficacy of low fat diets.

The disagreement comes in whether moving that arrow down from saturated fat to unsaturated fat is truly beneficial for weight management or cardiovascular health.

Good Fats and Bad Fats?

My own take on the good fat/bad fat controversy is as follows:

There are multiple types of saturated fats and multiple types of unsaturated fats and the scientific evidence is not currently robust enough to make the claim that replacing any saturated fat  with any unsaturated fat is a healthy change.

There is no evidence that low-fat or no fat dairy is healthier than full fat dairy (see here and here). Eating no, or low, fat yogurt with the natural fat replaced by sugar and other additives likely moves the arrow up, raising your risk. This kind of processed food gets a pass from mainstream nutritionists for some reason.

Saturated fat from pasture-raised pigs and cows consumed in moderation is not unhealthy or weight gain promoting.

In the end, Dr. Rimm and I agree on about 95% of the science and recommendations in his course.

Take a look and you can tell your friends that you just passed a Harvard course with flying colors!