In 1972 Dr. Robert Atkins published his “Diet Revolution” advocating a very low carbohydrate diet. In response the AMA attacked Atkins calling his “high fat” diet a “dangerous fraud.” When Atkins was called before a congressional committee to defend himself, he was publically ridiculed and humiliated. Meanwhile, two years later (in 1974), The Framingham Study again reported that men with low cholesterol have a strong association with colon cancer and premature death, but that there was no association between high cholesterol and sudden death. The water was getting muddied, but nobody outside the research community paid attention to the newly nuanced data and findings.
Enter Senator George McGovern, chairman of a U. S. Senate Select Committee on Nutrition and Human Needs (“the McGovern Commission”) and staunch supporter of agriculture since beginning his Congressional career in 1956. He was convinced that fat made us fat and was responsible for “killer diseases” like cancer and heart disease. In 1977, after only two days of very contentious hearings, his committee published the “Dietary Goals for the United States” (The McGovern Report). That was followed in 1980 by “Dietary Guidelines for Americans,” published jointly by HHS and USDA then and now every 5 years including the present iteration, published July 13, 2010. Again, the die was cast. There was no going back, in spite of mounting and persistent evidence. Government appointed scientists and processed food industry representatives would henceforth decide what to recommend we eat. What we eat had become the government’s business, and the business of big business.
In that same year as the McGovern Report (1977), the NIH reported on five diet-heart studies suggesting that a depressed level of HDL was the most reliable predictor of heart disease for men and women at all ages, but this went virtually unnoticed at the time. This finding was studied further by the NIH, but only after a substantial delay. It wasn’t until 1999 that a large scale, long term study confirmed that increasing HDL lowers CVD risk. Recent research indicates that it also lowers cancer risk, approximately 36% with every rise of 10 mg/dl. (http://www.webmd.com/cholesterol-management/news/20100615/healty-cholesterol-may-lower-cancer-risk)
In the meantime, NIH’s MRFIT study (1982, 13,000 men followed for 6 years) studied a low-fat, high carbohydrate diet with a focus on vegetable fat, which effectively lowered total cholesterol. Participants had more heart disease deaths than their “usual care” cohort. In addition, the lowest cholesterol levels were associated with mortality levels equivalent to the highest cholesterol levels. They were also associated with significantly more strokes, digestive diseases and cancers. This study was also ignored, but the focus did shift to lowering LDL instead of total cholesterol, perhaps due to the desire for a simple public health message. (http://wholehealthsource.blogspot.com/2009/07/mrfit-mortality.html)
Now, enter Big Pharma. By the late 1980’s sales of the first LDL cholesterol lowering statin drug had begun. As a result of public campaigns, people became familiar with their cholesterol numbers, and the difference between “good” and “bad” cholesterol entered the public consciousness. These campaigns were very effective. World-wide sales of statins in 2010 should top $20 billion; they are the most commonly prescribed drug of all time. However, 30 years later, there is no evidence that statins help women or anyone over the age of 65. (http://www.businessweek.com/magazine/content/08_04/b4068052092994_page_5.htm)
Meanwhile, Ancel Keys, father of the lipid hypothesis, lived on in Southern Italy to age 100, before coming home to die in 2004. Years earlier, however, according to Malcolm Kendrick, author of “The Great Cholesterol Myth,” Keys admitted (in 1997) that cholesterol in the diet has no effect on cholesterol levels in the blood. Keys is said to have said, “There's no connection whatsoever between cholesterol in food and cholesterol in blood. And we've known that all along.”
What is that he said, you say? Is it then possible that: dietary cholesterol does not have to be limited at all? that Total (blood) Cholesterol is irrelevant? that high LDL is not a critical metric, and that high HDL and lower triglycerides are more important for heart health? And finally, that those two goals are achievable, with weight loss by low-carb eating alone, with fish oil supplementation, and without statins?
When my doctor, an internist/cardiologist, looked at my blood tests, including my lipid panel, after a recent visit, he called to tell me the results. He concluded, exultant: “You’re going to live to be 105!” Hmmm… that’s longer than Keys.
© Dan Brown 12/12/10
Friday, December 31, 2010
Friday, December 10, 2010
The Nutrition Debate #3: Ancel Keys and the Lipid Hypothesis
Ancel Keys, a prominent University of Minnesota physiologist who was keenly interested in diet and nutrition, was attending a medical conference in Rome in 1951 when he learned “that heart disease was rare in some Mediterranean populations who consumed a lower fat diet. He noted, too, that the Japanese had low fat diets and low rates of heart disease. He hypothesized from these observations that fat was the cause of heart disease.”¹ These observations and associations have since come to be known as the Lipid Hypothesis.
Two years later, in 1953, Keys, now convinced that dietary fat was the cause of heart disease, published his “Six Country Analysis,” an epidemiological study. Years later, he published an updated version (1980, Harvard University Press) as the “Seven Countries Study.” In it Keys points out an association between dietary fat and mortality from heart disease. Critics pointed out then, and with increasing traction today, that Keys had data for 22 countries, but selected data from just 6 (later 7). As an example, Keys excluded France, a country with a high fat diet and low rates of heart disease. His detractors then and now claim that Keys had selected the data to support his hypothesis, and that that was bad science. Further, his was a retrospective analysis, not a prospective study, and thus did not prove causality. This distinction is a pretty fundamental precept of scientific investigation, but one that is often overlooked by the media and the lay public.
Meanwhile, the American Heart Association (AHA), founded in 1924, had “re-invented” itself in 1948 as a volunteer fundraising organization. In 1956 their TV fundraiser on all three networks urged Americans to reduce their intake of total fat, saturated fat, and cholesterol. Then, when President Eisenhower had his first heart attack in 1958, the AHA recommended Americans eat “heart-healthy” margarine, corn oil, breakfast cereal and skim milk, a diet that the President (and millions of Americans) unhappily complied with. Today, most health-conscious Americans still largely follow this diet, perhaps with the exception of margarine, which was basically a partially hydrogenated vegetable oil or trans fat. We are now told, and I certainly agree, that trans fats are really bad for us. But, we still (most of us) largely avoid eggs, butter, marbled beef and other fatty cuts of meat, and high cholesterol containing foods like liver and shrimp (and eggs, butter and cream!).
Meanwhile, by 1961 Ancel Keys had joined the Board of the AHA, the AHA had adopted Keys’s low-fat diet, and Keys himself made the cover of Time Magazine under the banner “Diet and Health.” Fat became public health enemy #1.
That same year the famous Framingham Heart Study, another epidemiological study of 5209 people begun in 1949, noted that men under 50 with elevated serum (blood) cholesterol were at greater risk of heart disease. However, these men were also more likely to smoke, be overweight, not exercise, and, although not noted, have high blood sugar. These first three observations became the famous “risk factors” that, to this day, are the mantra of the the public health establishment, the medical community, and the media who trumpet it. Little noted was the finding that for men over 50 there was no association between elevated serum cholesterol and heart disease.
There were, of course, opposing voices in the medical community, including senior researchers at Rockefeller and Yale and the U. of Pennsylvania. They and others pointed out that elevated triglycerides (and low HDL) were associated with increased risk of heart disease and that low fat, high carbohydrate diets caused elevated triglycerides, but their findings were disregarded and their voices ignored. By 1972 the federal government’s WIC program only allowed skim or low-fat milk for kids over age 2. The die was cast. We had started down the road of government intervention in what we eat.
¹ The timeline history of heart disease in this and the succeeding installment draws heavily from a piece by the same title published by Diet Heart Publishing (http://dietheartpublishing.com).
© Dan Brown 12/7/10
Two years later, in 1953, Keys, now convinced that dietary fat was the cause of heart disease, published his “Six Country Analysis,” an epidemiological study. Years later, he published an updated version (1980, Harvard University Press) as the “Seven Countries Study.” In it Keys points out an association between dietary fat and mortality from heart disease. Critics pointed out then, and with increasing traction today, that Keys had data for 22 countries, but selected data from just 6 (later 7). As an example, Keys excluded France, a country with a high fat diet and low rates of heart disease. His detractors then and now claim that Keys had selected the data to support his hypothesis, and that that was bad science. Further, his was a retrospective analysis, not a prospective study, and thus did not prove causality. This distinction is a pretty fundamental precept of scientific investigation, but one that is often overlooked by the media and the lay public.
Meanwhile, the American Heart Association (AHA), founded in 1924, had “re-invented” itself in 1948 as a volunteer fundraising organization. In 1956 their TV fundraiser on all three networks urged Americans to reduce their intake of total fat, saturated fat, and cholesterol. Then, when President Eisenhower had his first heart attack in 1958, the AHA recommended Americans eat “heart-healthy” margarine, corn oil, breakfast cereal and skim milk, a diet that the President (and millions of Americans) unhappily complied with. Today, most health-conscious Americans still largely follow this diet, perhaps with the exception of margarine, which was basically a partially hydrogenated vegetable oil or trans fat. We are now told, and I certainly agree, that trans fats are really bad for us. But, we still (most of us) largely avoid eggs, butter, marbled beef and other fatty cuts of meat, and high cholesterol containing foods like liver and shrimp (and eggs, butter and cream!).
Meanwhile, by 1961 Ancel Keys had joined the Board of the AHA, the AHA had adopted Keys’s low-fat diet, and Keys himself made the cover of Time Magazine under the banner “Diet and Health.” Fat became public health enemy #1.
That same year the famous Framingham Heart Study, another epidemiological study of 5209 people begun in 1949, noted that men under 50 with elevated serum (blood) cholesterol were at greater risk of heart disease. However, these men were also more likely to smoke, be overweight, not exercise, and, although not noted, have high blood sugar. These first three observations became the famous “risk factors” that, to this day, are the mantra of the the public health establishment, the medical community, and the media who trumpet it. Little noted was the finding that for men over 50 there was no association between elevated serum cholesterol and heart disease.
There were, of course, opposing voices in the medical community, including senior researchers at Rockefeller and Yale and the U. of Pennsylvania. They and others pointed out that elevated triglycerides (and low HDL) were associated with increased risk of heart disease and that low fat, high carbohydrate diets caused elevated triglycerides, but their findings were disregarded and their voices ignored. By 1972 the federal government’s WIC program only allowed skim or low-fat milk for kids over age 2. The die was cast. We had started down the road of government intervention in what we eat.
¹ The timeline history of heart disease in this and the succeeding installment draws heavily from a piece by the same title published by Diet Heart Publishing (http://dietheartpublishing.com).
© Dan Brown 12/7/10
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