By the time the mid-1950’s rolled around, the American scientific community was becoming increasingly alarmed at the growing trend of people dying of heart attacks. Society was changing quickly. Where once people had mostly lived in rural areas doing physical labor each day, the modern American was urban and desk bound. Though advances in medicine were rapidly doing away with the threat of infectious disease, long the number one killer, heart disease was rising rapidly. Luckily, one Minnesota scientist, a man named Dr. Ancel Keys, believed he had the answer. Dr. Keys was one of the first to note that the rise in heart disease in the U.S. correlated quite well with a rise in meat consumption. The American economy was booming, and as American’s became wealthier, they were stuffing more meat down their gullets. In 1955, with absolutely no proof whatsoever, Dr. Keys went before the World Health Organization and declared his lipid theory, which stated that dietary fat raised cholesterol, which in turn increased heart disease. According to Dr. Keys, the only way to reverse the terrible trend was for people to switch a large part of their consumption of animal fats to healthier vegetable oils.
In 1958, in an attempt to actually prove his theory, Dr. Keys launched what became known as the Seven Country Study, one of the largest dietary studies in history. While Dr. Keys collected massive amounts of data, he also hit the road, promoting his lipid theory throughout the 1960’s. Though the general public was less than interested, the scientific community largely embraced the lipid theory, especially as several smaller observational studies were released supporting it.
It was at this point that a man named Dr. Ivan Frantz entered the picture. Dr. Frantz, also from Minnesota, was a colleague and fervent supporter of Dr. Keys’ lipid theory. In 1968, wanting to forever end debate on the subject, Dr. Frantz concocted one of the most precise dietary studies in history. The problem then, and still today, with dietary studies was that they were based off of observational studies, where volunteers kept food journals that reported what they ate. These studies had a significant problem in that it was not unusual for people to forget and/or lie when recording what they had eaten. Dr. Frantz got around this issue by not using volunteers, but rather 9,500 mental patients housed in Minnesota’s psychiatric wards. Since the diet of the patients was controlled, Dr. Frantz could easily randomly assign half a diet high in animal fats and the other half a diet high in vegetable oils. Since this was the 1960’s, the state officials running the psychiatric wards were perfectly a-okay with all of this.
In 1970, Dr. Keys released the results of his Seven Country Study, which lo and behold proved his lipid theory utterly and completely correct. The idea that high cholesterol caused heart disease fully entered the public sphere; and health organizations, the U.S. government, and oilseed farmers began a concerted effort to get people to switch from animal fats to vegetable oils. As a result of these efforts, consumption of red meat and animal fats began to decline and consumption of vegetable oils increased. It was perhaps the largest and most rapid shift in American diets in history.
Dr. Frantz was eager for his study to be the proverbial nail in the coffin of animal fats. However, when he started going through his data in 1973, he found things not to be as expected. While the vegetable oil group most definitely did have lower cholesterol levels, their risk of dying of heart disease actually increased. This left Dr. Frantz in a befuddled mess, at least until a group of Australian scientists released a long-term observational study supporting the lipid theory later that year. With such further evidence available, Dr. Frantz assumed that he must have fucked up his own study somehow, put all of his data in his basement, and forgot about it.
The lipid theory remained concrete science for the next forty years, a period that saw vegetable oils become a significant portion of the American diet. However, cracks began to appear in the claim in 2011, when a scientist found Dr. Frantz’s data and published the results, causing a huge stir in the scientific world. This was followed by a review of both the Australian study and the all important Seven Country Study, both of which revealed that data had been left out that would’ve supported Dr. Frantz’s findings. Forty years of dietary advice had been built on a house of cards. While scientists continue to disagree on what this all means, it is worth noting that the decline in animal fat consumption resulted in an increase in sugar consumption, since vegetable oils tend to taste like garbage on their own. This increase has been tied to rising obesity and diabetes rates. Happy eating.
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