In Summary
* Last week we looked at the origins of beliefs about cholesterol and heart disease. This week we look at the origins of beliefs about dietary fat and heart disease.
* American soldiers were the subject of some studies from the 1950s-1970s. Some researchers thought diet played a part in build-up of fatty deposits; others didn’t consider diet to be a factor.
* The main researcher featured in last week’s note also features in this week’s note – Dr Ancel Keys.
* In 1953, Keys presented a graph showing a strong relationship between deaths from heart disease and fat calories as a percentage of total calories for men aged 55-59.
* The main challenge to this work came from two researchers called Yerushalmy & Hilleboe. They presented the same data but for 22 countries questioning why Keys ‘cherry-picked’ just 6 countries. The 22 countries did not show much relationship at all.
* Yerushalmy & Hilleboe presented further challenges to Keys’ claim about heart deaths and dietary fat: i) the definitions of heart disease chosen; ii) there were stronger associations with other dietary factors than fat and iii) looking at fat and all causes of death flipped conclusions around.
* Other researchers of the era also challenged Keys. Keys was dismissive of those who disagreed with him.
* These challenges were occurring in the mid-1950s, as Keys was starting his Seven Countries Study. Many researchers were needed for the Seven Countries Study. Keys collaborated with the ones who agreed with him.
Zoe
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