Recently, an article published in the British Medical Journal attracted a lot of interest because it busts the myth about a decades old dogma (1). Aseem Malhotra, M.D., explained why saturated fat consumption is not a major risk for heart disease, but the common fractured foods and sugar used to replace saturated fats are indeed.
Dr. Malhotra chats with us about why the often repeated ill-advice about saturated fats not only diverts people from good dietary advice that is effective, but also can be harmful in itself. We will discuss what really works in reducing heart disease risk and why.
Just as it’s impossible to unring a bell or put the toothpaste back into the tube, the false belief that saturated fat is a major culprit in heart disease is almost impossible to correct. There’s a large food industry built around this falsehood. Yet, a few myth-busting researchers dare to look at the facts and point out the truth. And, that is what we try to do here in this column. Why bother? Because if you believe the wrong facts and ignore more helpful information, you increase your risk of developing a serious debilitating disease.
Dr. Malhotra is an interventional cardiologist based in London. He is a member of the Academy of Medical Royal Colleges Obesity Group, cardiologist adviser to Britain’s National Obesity Forum and science director of the campaign group Action on Sugar.
Passwater: Why did you become a cardiologist?
Malhotra: I was fascinated with the heart from a very young age. My late brother, who was born with a hole in his heart, died very suddenly after a viral illness caused him to go into crashing heart failure. I always felt medicine was not only an extremely interesting subject, but also a noble profession where doctors could really make a positive difference in other people’s lives.
Passwater: Omega-3 polyunsaturated and omega-9 monounsaturated fats are heart healthy, and manmade trans-fats are unhealthy. Have saturated fats been wrongly maligned?
Malhotra: I think we have been over-simplistic in labeling all foods high in saturated fat as bad, which is also directly related to the over-emphasis on blood cholesterol. We should be concentrating more on food groups. And there is some evidence that dairy foods, which have plenty of nutritional qualities, may be cardio-protective.
What most people don’t realize is that saturated fat, in addition to raising so-called bad LDL cholesterol, raises good HDL cholesterol to the same level. Thus, it does not affect the total-cholesterol-to-HDL ratio, which is a more reliable marker of heart disease risk.
I am not for one minute suggesting that people over-indulge in saturated fat, but certainly from the evidence I have seen, the demonization of saturated fat has resulted in increased consumption of refined carbohydrates, which has resulted in greater obesity, and, in my view, has a stronger implication in heart disease. Furthermore, there is increasing evidence to suggest that excess consumption of omega-6 in vegetable oils may be atherogenic (i.e., damaging to the coronary arteries) by oxidizing LDL cholesterol particles.
Malhotra: The dogma of low-fat diet is damaging public health and contributing to the obesity epidemic, and this has to stop.
Passwater: What has the response been?
Malhotra: I have been overwhelmed by hundreds of supportive e-mails, including many from very well-respected academics around the world. There has, of course, been criticism from some who have tunnel vision and find it difficult to change their beliefs and others with vested interests including co-opted scientists.
Passwater: Your publication is a “call to action” to focus on the real causes of heart disease and do away with the nonsense. Several studies have established that saturated fat is not related to heart disease. A 2010 meta-analysis published in the American Journal of Clinical Nutrition by Oakland Research Institute researchers (2) examined 21 studies of dietary saturated fat and the risk of coronary heart disease, stroke and cardiovascular disease, and found no association. The researchers concluded, “A meta-analysis of prospective epidemiologic studies showed that there is no significant evidence for concluding that dietary saturated fat is associated with an increased risk of coronary heart disease or coronary heart disease inclusive of stroke.”
How did this nonsense start anyway? Wasn’t it based on partial facts contrived solely to support an otherwise unfounded belief?
The Seven Countries epidemiological study led by Dr. Ancel Keys was started in the late 1950s and became the cornerstone of the “avoid saturated fat” mantra. A critical review of the Seven Countries Study by statisticians Drs. R.L. Smith and E.R. Pinckney revealed “a massive set of inconsistencies and contradictions,” leading to the conclusion that the “study cannot be taken seriously by the objective and critical scientist.”
As one example, the mortality rate in Finland was almost seven times higher than in Mexico, although the fat consumption was identical. The so-called “French Paradox” is another example. They intentionally left out countries where people eat a lot of fat, but have little heart disease, such as Holland and Norway. They intentionally left out countries where fat consumption is low, but the rate of heart disease is high, such as Chile.
The examples selected were chosen to fit their theory, rather than looking at all the available data. If ANY OTHER seven countries had been included, the opposite relationship is seen. In order to gain support for their theories, some scientists resort to “cherry-picking” where they include only what fits the theory instead of including all the data. You can sometimes see this in meta-analyses where scientists “adjust” inclusion criteria to consider mostly the studies that support the premise they want to “prove” and reject others from being considered due to one technicality or another of the inclusion process.
Malhotra: Yes. These are very valid points. The difficulty in nutrition is that it’s quite difficult to perform robust dietary studies. Scientists often go in looking for a specific answer to prove their own preset beliefs. But, this is not good science.
Passwater: Does the body handle a calorie of sugar the same as a calorie of fat?
Malhotra: I am glad you asked this question. Definitely not, and it’s extremely naïve of both the profession and the public to presume that a calorie of bread, a calorie of meat and a calorie of alcohol are handled in the same way by the complex metabolic pathways in the body. We know from the PREDIMED study, for example, that supplementing a Mediterranean diet with four tablespoons of extra-
virgin olive oil daily (which is approximately 500 calories) reduces the risk of heart attack and stroke by approximately 30% in a high-risk population. Meanwhile, daily consumption of 139 calories of sugar, typical of a can of cola, is associated with a 22% increased risk of developing type-2 diabetes, independent of body weight!
Passwater: You also discussed that blood total cholesterol was also not the major problem. Are there specific blood lipoproteins that affect risk more than total cholesterol? Even total LDL cholesterol and total HDL cholesterol?
Malhotra: Yes. I think concentrating on LDL cholesterol alone as a risk factor for heart disease is too simplistic and just bad science. Cholesterol is not only an extremely complex molecule, but also is vital for life because it is necessary for proper brain function and hormone synthesis. It is a marker in the blood, but, in my view, high triglycerides and low HDL cholesterol as markers of the metabolic syndrome are more important.
Passwater: Yet, millions of people are prescribed cholesterol-lowering drugs.
Malhotra: The evidence is strong that in those with established heart disease, the benefits of statins outweigh the risks. But in those without heart disease, the evidence is weak. Furthermore, real world data reveal that as many as one in five people will discontinue the drug due to experiencing unacceptable side effects such as muscle pain, stomach complaints, short-term memory loss and erectile dysfunction; there is also an increased risk of developing type-2 diabetes. Cutting the millions of people who do not need to take statins would dramatically reduce unnecessary suffering and health care costs worldwide.
Passwater: Then, what is your advice for a heart-healthy diet?
Malhotra: The Mediterranean diet still has the strongest evidence base. A diet that is high in oily fish, extra-virgin olive oil, nuts, plenty of whole fruit (NO juice) and vegetables, and a moderate intake of dairy. A heart-healthy diet is low in refined carbohydrates, and therefore avoids white bread, white pasta and sugar as much as possible. Choose butter over margarine, and always choose the non-processed full fat yogurt. Not only will this diet be heart healthy, but it will also reduce the risk of developing type-2 diabetes, cognitive decline, cancer and gaining weight.
Passwater: Good advice. Thank you, Dr. Malhotra. WF
Dr. Richard Passwater is the author of more than 45 books and 500 articles on nutrition. Dr. Passwater has been WholeFoods Magazine’s science editor and author of this column since 1984. More information is available on his Web site, www.drpasswater.com.
1. A. Malhotra, “Saturated Fat Is not the Major Issue,” BMJ 347:f6340 (2013).
2. P.W. Siri-Tarino, et al., “Meta-Analysis of Prospective Cohort Studies Evaluating the Association of Saturated Fat With Cardiovascular Disease,” Am. J. Clin. Nutr. 91 (3), 535–546 (2010).
Published in WholeFoods Magazine, March 2014