Ancel Keys

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Ancel Benjamin Keys (born January 26, 1904 in Colorado Springs , † November 20, 2004 in Naples ) was an American nutritionist who studied hunger and the physiological effects of dietary fats.

Life

Keys lived in both the US and Europe:

Childhood and youth

Keys was born in Colorado Springs in 1904; his parents were young people with no schooling who soon moved with him to California and initially settled in San Francisco . Keys experienced the San Francisco earthquake as a two-year-old, which destroyed his father's print shop, and the family moved to Berkeley . When Keys tried to stun a fly with chloroform on his eighth birthday, he sedated himself. This experience, he later said, sparked his interest in science.

After graduating from Community College with honors after three years, Keys worked for a short time at Woolworths before returning to Berkeley for a Masters in Biology, followed by a PhD from the Scripps Institute of Oceanography . In 1930 he traveled to Copenhagen to work with Nobel Prize winner August Krogh and to conduct research on eels. He then did his doctorate again at Cambridge , he received a doctorate in animal physiology from King's College .

When Keys returned to the United States in 1933, he began researching exercise physiology at the Fatigue Laboratory at Harvard . His first project was a study of the effects of living at altitude on blood oxygenation, which he believed could be of practical use to copper miners in Chile. He traveled to the Chilean Andes with a small group of people and gradually acclimatized them to an altitude of 22,000 feet.

Act

Development of the K rations

In 1939 he was asked by the United States Department of War to develop and test a food ration for parachute troops. At that time he was head of the Physiological Hygiene Laboratory at the University of Minnesota , where he also conducted his studies on human nutrition, which would extend over the next several decades.

The food ration for paratrooper troops was called K rations ( K for Keys) during the project . He had food with a physiological calorific value of 3,200 kcal packed in watertight boxes as a daily ration, which was divided into breakfast, lunch and dinner. The jar contained meat or cheese, biscuits, a bar of chocolate and candy, coffee, lemon or soup powder, chewing gum, toilet paper and cigarettes.

Minnesota Starvation Experiment

With millions of people suffering from the effects of a disrupted food supply in the wake of World War II, Keys began a research project called the Minnesota Starvation Experiment :

He had the effects of massive malnutrition on the human body closely monitored and then compared different pre-defined nutritional interventions to restore the health of the emaciated test subjects. He found the test subjects in Civilian Public Service Workcamps among conscientious objectors, especially members of free churches , who did not want to fight but were still prepared to endanger their health for science.

The men involved were fed only root vegetables, black bread and simple starchy foods for three months, were exposed to semi-starvation , targeted malnutrition, while they had to walk an average of 22 miles (35 km) per week.

The results were published in 1950 in the form of a book entitled Biology of Human Starvation , which is still considered authoritative in the early 21st century.

In the course of the experiment, most of the participants lost about 25% of their weight and many suffered from anemia , fatigue , apathy , extreme weakness , irritability , neurological deficits and edema of the lower extremities.

Seven Country Study

In 1951 Keys took a sabbatical with his family in Oxford. In this context, an Italian colleague claimed that heart disease did not occur in Italy, to which Keys initially reacted skeptically and set up a laboratory in Naples with his wife Margaret. Here he soon verified the low incidence of heart disease among Neapolitans and also found that they had very low serum cholesterol levels.

Keys and his wife then toured several European and African countries to measure the population's cholesterol levels: Little by little, a pattern emerged suggesting that a diet high in saturated fat raised serum cholesterol, which Keys did regarded as a major cause of coronary artery disease . When Keys first presented his ideas on dietary heart disease in an international setting to the World Health Organization in 1955 , he was met with skepticism. Sir George Pickering asked for more evidence from Keys, who felt humiliated when he was unable to provide it.

So he spent the next 15 years with the design, implementation and analysis of his Seven Countries Study (Engl. Seven Countries Study ): From 1958 to Keys was performing over a period of 15 years, studies in seven countries, the correlation between Proportion of animal fats in the diet and the incidence of coronary artery disease appeared to demonstrate. The study was conducted on 12,000 healthy middle-aged men in Italy, the Greek Islands, Yugoslavia, the Netherlands, Finland, Japan, and the United States and published in book form by Harvard Press in 1980 . She made a significant contribution to popularizing the so-called Mediterranean diet , which is rich in fruit and vegetables, bread and olive oil with fish and dairy products, as a supposed prevention of heart disease.

Some of the results of the study are viewed very critically. Although he collected data from 22 countries, he would have limited his publication to seven of these countries (in fact, he collected data from people from exactly seven countries for this study, whose individual diet, health and cause of death were observed for over 30 years. The 22 countries come from an older study from 1953, in which countries were actually examined, but whose initial data were of poor quality.). If you include all countries in the comparison, there is no positive correlation between the proportion of animal fats in the diet and the incidence of heart disease. The raw data of the study, which remained under lock and key for a long time, even suggested an exactly reverse correlation (“citation needed”). According to Udo Pollmer , the seven-country study can now be viewed as “a large-scale fraud”. The increased incidence of heart disease in the western world in the 20th century can also be explained by other factors, such as increased sugar and white bread consumption and a lack of exercise .

Minnesota Coronary Experiment

Ten years after the start and two years after the results of the seven-country study were first published, Ivan Frantz and Ancel Keys started a large-scale intervention study - the Minnesota Coronary Experiment . It was the largest clinical test of a specific form of therapy ever carried out at the time, in this case the replacement of saturated dietary fats with foods with a naturally high or artificially increased proportion of linoleic acid . With this study Keys wanted to substantiate the results of the seven-country study.

The study was appropriately planned as a randomized, blinded study, carried out according to the plan and completed in 1973, but only published in small excerpts many years later as a conference contribution and doctoral thesis, but not as a classic paper. Raw data and evaluations were found by chance in the estate of the study director Ivan Frantz in 2013 and were therefore only accessible to the public a decade after Keys' death. The study showed no benefit from the change in food composition, but even an increase in cardiovascular mortality in older patients (over 65 years of age). The rediscovery of the study and the controversial results were extensively discussed above all, but not only in the English-language media, especially in the context of the conflicts of interest surrounding proponents of the "Diet Heart Hypothesis".

The term body mass index (BMI)

In an article published in 1972 Keys coined the term body mass index (BMI) after the corresponding calculations had already been made by Adolphe Quetelet around 1832 ; Keys, however, assumed that the index should be applied to whole populations as a statistical mean.

Awards

In 1980 Keys received the honorary title of academic from the Finnish President .

Publications

With his wife, a biochemist, Keys wrote the books Eat Well and Stay Well and How to Eat Well and Stay Well the Mediterranean Way . Another book, The Benevolent Bean , he published alone.

Notes / individual evidence

  1. ^ T. Tucker: The Great Starvation Experiment: Ancel Keys and the Men Who Starved for Science. 2006
  2. a b c d e f g h Biographical notes on Ancel Keys and Salim Yusuf: Origins and significance of the Seven Countries Study and the INTERHEART Study.
  3. a b L. M. Kalm, RD Semba: They Starved So That Others Be Better Fed: Remembering Ancel Keys and the Minnesota Experiment. In: The Journal of Nutrition , 2005
  4. a b c J. E. Brody: Dr. Ancel Keys, 100, Promoter of Mediterranean Diet, Dies. In: New York Times , 2004.
  5. Overweight worldwide (PDF; 1.9 MB). Quarks & Co , WDR report on the Crete Diet, February 2004.
  6. a b Ancel Keys 7 Countries Study: Still accurate, actionable and relevant
  7. Udo Pollmer : Study on Heart Attack Risk - Is Cholesterol Harming? Invented everything! In: Deutschlandfunk Kultur . ( deutschlandfunkkultur.de [accessed on July 23, 2017]).
  8. ^ What if Bad Fat is Actually Good for You? In: Men's Health . October 10, 2007 ( menshealth.com [accessed July 23, 2017]).
  9. ^ Samuel B. Green: Forestry in Minnesota. Pioneer Press Company, St. Paul, Minn. 1902, doi : 10.5962 / bhl.title.56117 .
  10. Christopher E. Ramsden, Daisy Zamora, Sharon Majchrzak-Hong, Keturah R. Faurot, Steven K. Broste: Re-evaluation of the traditional diet-heart hypothesis: analysis of recovered data from Minnesota Coronary Experiment (1968-73) . In: BMJ . tape 353 , April 12, 2016, ISSN  1756-1833 , doi : 10.1136 / bmj.i1246 , PMID 27071971 .
  11. Minnesota Coronary Experiment — Trying To See In A Blizzard? - Boston Heart. Retrieved May 11, 2020 .
  12. Peter Whoriskey closePeter WhoriskeyReporter focusing on investigations of economic, financial issuesEmailEmailBioBioFollowFollowReporter: This study 40 years ago could have reshaped the American diet. But it was never fully published. Retrieved May 11, 2020 .
  13. Editorial Board: The heretical Minnesota heart study: When science stops asking questions. Retrieved May 11, 2020 .
  14. "Good" fat - not that healthy at all? April 13, 2016, accessed May 11, 2020 .
  15. expert reaction to study on vegetable oil, cholesterol levels, and risk of heart disease | Science Media Center. Retrieved May 11, 2020 (American English).
  16. Isn't vegetable oil as healthy for the heart as you thought? Retrieved May 11, 2020 .
  17. Old study shakes nutritional dogma. April 18, 2016, accessed May 11, 2020 .
  18. Garabed Eknoyan: Adolphe Quetelet (1796–1874) —the average man and indices of obesity. Nephrol. Dial. Transplant. (2008) 23 (1): 47-51. doi: 10.1093 / ndt / gfm517 .
  19. Ancel Keys: "Indices of relative weight and obesity". In: Journal on Chronic Diseases . Oxford 25. 1972, 6, pp. 329-343. ISSN  0021-9681 .
  20. YLE Uutiset (ed.): Presidentti nimitti kaksi uutta akateemikkoa .