Ancel Keys#Keys equation

Ancel Benjamin Keys was born in Colorado Springs on January 26, 1904, the son of Benjamin Pious Keys (1883–1961) and Carolyn Emma Chaney (1885–1960), the sister of actor and director Lon Chaney (1883–1930).{{cite news | first = Jane E. | last = Brody | title = Ancel Keys, 100, Promoter of the Mediterranean Diet, Dies | date = November 23, 2004 |url=https://www.nytimes.com/2004/11/23/obituaries/23keys.html | work = The New York Times | access-date = February 5, 2011}} In 1906 they moved to San Francisco before the 1906 San Francisco earthquake struck.{{cite news | first = Patricia | last = Sullivan | title = Ancel Keys, K Ration Creator, Dies | date = November 24, 2004 |url=https://www.washingtonpost.com/wp-dyn/articles/A7213-2004Nov23.html | newspaper = The Washington Post | access-date = February 5, 2011}} Shortly after the disaster, his family relocated to Berkeley where he grew up. Keys was intelligent as a boy; Lewis Terman, a noted psychologist and inventor of the Stanford-Binet IQ Test, described him as intellectually "gifted". During his youth, he left high school to pursue odd jobs, such as shoveling bat guano in Arizona, being a powder monkey in a Colorado mine, and working in a lumber camp.{{cite web |url=http://mbbnet.umn.edu/hoff/hoff_ak.html | title = Meet Monsieur Cholesterol | access-date = February 5, 2011 | last = Hoffman | first = William | year = 1979 | work = University of Minnesota | publisher = University of Minnesota}} He eventually finished his secondary education and was admitted to the University of California at Berkeley in 1922.

At the University of California, Berkeley, Keys initially studied chemistry, but was dissatisfied and took some time off to work as an oiler aboard the American President Lines ship SS President Wilson, which traveled to China. He then returned to Berkeley, switched majors, and graduated with a B.A. in economics and political science (1925) and M.S. in zoology (1928).

For a brief time, he took up a job as a management trainee at Woolworth's, but returned to his studies at Scripps Institution of Oceanography in La Jolla on a fellowship.

In 1930, he received his Ph.D. in oceanography and biology from UC Berkeley. He was then awarded a National Research Council fellowship that took him to Copenhagen, Denmark to study under August Krogh at the Zoophysiological Laboratory for two years.{{cite book | last1 = Zadunaisky | first1 = JA | title = Fish Physiology | chapter = The Chloride Cell: The Active Transport of Chloride and the Paracellular Pathways | volume = 10 | editor1= William Stewart Hoar |editor2=David J. Randall | publisher = Academic Press | year = 1969 | pages = 130–136 | chapter-url=https://books.google.com/books?id=8fuEB7O3IqIC&q=ancel%20keys%20willmer&pg=PA130 | access-date = February 5, 2011 | isbn = 978-0-12-350430-2 | quote = Ancel Keys was a fellow of the National Research Council of America, who did the perfusion experiment leading to the observation of chloride secretion in the Zoophysiological Laboratory in Copenhagen, Denmark, under the direction of August Krogh.}} During his studies with Krogh, he studied fish physiology and contributed numerous papers on the subject.

Once his fellowship ended, he went to Cambridge but took some time off to teach at Harvard University, after which he returned to Cambridge and earned a second Ph.D. in physiology (1936).

While doing fish research at Scripps, Keys would use statistical regressions to estimate the weight of fish from their length, at that time a pioneering use of biostatistics.{{cite web |url=http://mbbnet.umn.edu/firsts/blackburn_h.html | title = Ancel Keys | access-date = February 5, 2011 | last = Blackburn, MD| first = Henry | year = 1998 | work = University of Minnesota | publisher = University of Minnesota}} Once in Copenhagen (1931), he continued to study fish physiology and developed techniques for gill perfusion that provided evidence that fish regulated their sodium by controlling chloride excretion through their gills.{{cite journal | title = 'Chloride secreting cells' in the gills of fishes, with special reference to the common eel | first2 = EN | journal = The Journal of Physiology | last2 = Willmer | year = 1932 | first1 = Ancel | last1 = Keys | volume = 76 | issue = 3 | pages = 368–380| pmid = 16994355 | doi = 10.1113/jphysiol.1932.sp002932 | pmc = 1394694}}{{cite journal | title = The determination of chlorides with the highest accuracy | journal = Z. Vergl. Physiol. | year = 1931 | first = Ancel | last = Keys | volume = 15 | issue = 2 | pages = 352–363| doi = 10.1007/BF00339114 | s2cid = 28971898 }} He would also use this perfusion method to study the effects of adrenaline and vasopressin ("pitressin") on gill fluid flow{{cite journal | doi = 10.2307/1537248 | title = Branchial Responses to Adrenaline and to Pitressin in the eel | journal = Biological Bulletin | year = 1932 | first = Ancel | last = Keys |author2=J.B. Bateman | volume = 63 | issue = 2 | pages = 327–336|url=http://www.biolbull.org/cgi/reprint/63/2/327.pdf | access-date = February 5, 2011| jstor = 1537248 }} and osmotic regulation in fishes.{{cite journal | title = The Mechanism of Adaptation to Varying Salinity in the Common Eel and the General Problem of Osmotic Regulation in Fishes | journal = Proceedings of the Royal Society B | year = 1933 | first = Ancel | last = Keys | volume = 112 | issue = 776 | pages = 184–199 | jstor=81638 | doi=10.1098/rspb.1933.0002| bibcode = 1933RSPSB.112..184K | doi-access =free }} He also designed an improved Kjeldahl apparatus, which improved upon Krogh's earlier design, and allowed for more rapid determination of nitrogen content in biological samples.{{cite journal | title = A Rapid Micro-Kjeldahl Method | journal = The Journal of Biological Chemistry | year = 1939 | first = Ancel | last = Keys | volume = 132 | pages = 181–187|url=http://www.jbc.org/content/132/1/181.short | access-date = February 5, 2011 | quote = A micro-Kjeldahl method is described. The method is more rapid than the ordinary macro-Kjeldahl procedure and is not appreciably less accurate | issue=1| doi = 10.1016/S0021-9258(18)73407-8 | doi-access = free }} This would prove useful for activities as diverse as determining the protein content in grasshopper eggs{{cite journal | doi = 10.2307/1537901 | title = Nitrogen content and distribution in eggs of Melanoplus differentialis during embryonic development | journal = Biological Bulletin | year = 1940 | first = Carolyn | last = Trowbridge |author2=Joseph Hall Bodine | volume = 79 | issue = 3 | pages = 452–458|url=http://www.biolbull.org/cgi/reprint/79/3/452.pdf | access-date = February 5, 2011| jstor = 1537901 }} and anemia in humans.{{cite journal | doi = 10.1172/JCI103087 | title = The anemia of liver disease: observations on its mechanism. | journal = Journal of Clinical Investigation | year = 1955 | first = James H. | last = Jandi | volume = 34 | issue = 3 | pages = 390–404| pmid = 14354009 | pmc = 438641}}

While at Harvard's Fatigue Laboratory, he was inspired by his Cambridge mentor Joseph Barcroft's ascent to the top of Tenerife's highest peak and his subsequent reports. Keys wrote up a proposal for an expedition to the Andes, suggesting the study could have practical value for Chilean miners who worked at high elevations. He was given the go-ahead and, in 1935, assembled a team to study the effects of high altitude on the body, such as how it affects blood pressure. He spent a couple of months at 9,500 feet (3,000 m.), and then five weeks at elevations of 15,000 to 20,000 feet (4,500 to 6,000 m.).

He noted there was no good way of predicting how well humans might adapt to high altitude, even if they adapted well to medium altitudes, a problem for potential pilots in a time before pressure control had become practical.{{cite journal | title = The Physiology of Life at High Altitudes | journal = The Scientific Monthly | year = 1936 | first = Ancel | last = Keys | volume = 43 | issue = 4 | pages = 289–312| jstor = 16163| bibcode = 1936SciMo..43..289K }} It was from these studies that he outlined the phenomenon of human physiological adaptation to environmental changes as a predictable event, a novel idea in a time when such parameters as blood pressure and resting heart-rate were considered immutable characteristics of individuals.{{cite journal |vauthors=Kalm L, Semba R |title=They starved so that others be better fed: remembering Ancel Keys and the Minnesota experiment |journal=J Nutr |volume=135 |issue=6 |pages=1347–1352 |year=2005 |pmid=15930436|doi=10.1093/jn/135.6.1347 |doi-access=free }}{{cite journal | doi = 10.1098/rspb.1938.0043 | title = Individual Variations in Ability to Acclimatize to High Altitude | journal = Proceedings of the Royal Society B | year = 1938 | first1 = Ancel | last1 = Keys | first2 = Bryan H. C. |last2=Matthews |first3=W. H. |last3=Forbes |first4=Ross A. |last4=McFarland | volume = 126 | issue = 842 | pages = 1–24| jstor=82153| bibcode = 1938RSPSB.126....1K | s2cid = 128707808 | doi-access = }}

{{Main|K-ration}}

File:KRation Dinner.JPG dinner. All the components were intended to fit into a box which would fit into a soldier's pocket]]

In 1936, Keys was offered a position at the Mayo Foundation in Rochester, where he continued his studies in physiology. He left after a year, citing an intellectually stifling environment where research was secondary to clinical "doc business" and playing bridge.

In 1937, he left the Mayo Foundation to teach physiology at the University of Minnesota,{{cite news | first = Christopher | last = Reed | title = Ancel Keys The dietician who promoted the virtues of the Mediterranean diet | date = December 8, 2004 |url=https://www.theguardian.com/news/2004/dec/08/guardianobituaries1 | work = The Guardian | access-date = February 5, 2011}} where he founded the Laboratory of Physiological Hygiene. His earlier research on human physiology led to an assignment with the Army Quartermaster Corps, where they worked to develop a more portable and nonperishable ration that would provide enough calories to sustain soldiers (such as paratroopers) in the field for up to two weeks.{{cite journal | title = From Harvard to Minnesota: Keys to our History | journal = Exercise and Sport Sciences Reviews | year = 1992 | first = ER | last = Buskirk | volume = 20 | pages = 1–26| pmid = 1623883 | quote = Based on an appeal from the Army Quartermaster Corps, experiments to design and test rations for the promotion and maintenance of combat effectiveness for paratroopers were undertaken. Neither Keys nor the military was particularly interested in vitamins, but rather they wanted to put calories into a small packet of nonperishable food  ... the Keys or K-ration was designed in the Laboratory and at field test sites in both hot and cold areas on the North American continent. | doi=10.1249/00003677-199200200-00001| doi-access = free }}

This development did not begin without some turbulence. His colleague, Elsworth Buskirk, recalled:

{{blockquote|When it appeared that the U.S. would be in World War II, Keys went to the Quartermaster Food and Container Institute in Chicago to inquire about emergency rations. The story goes that he was told to go home and leave such things to the professionals. Undissuaded, he went to William Wrigley's office and secured $10,000 for the development of an emergency ration. Then, he went to the Cracker Jack Company. They couldn't supply money, but did provide the water-tight small box concept. The result was the K-ration in sealed Cracker Jack boxes.}}

Once the basic design had been completed, the Navy, through the National Research Council, funded the testing of the K-rations on its sailors to determine their feasibility as a temporary and mobile food source. The initial ingredients of the K-ration were procured at a local Minneapolis grocery store—hard biscuits, dry sausage, hard candy, and chocolate. The final product was different from Keys' original ingredients, but most of Keys' suggestions made it to the final product. The rations weighed only {{convert|28|oz|abbr=on}}, but provided 3200 calories per day. Though several sources claim the name was unrelated to Keys,{{cite conference|url=http://qmfound.com/history_of_rations.htm |contribution=Rations: The History of Rations |access-date=February 6, 2011 |archive-url=https://web.archive.org/web/20110208042157/http://www.qmfound.com/history_of_rations.htm |archive-date=February 8, 2011 |publisher=The Quartermaster School |via=U.S. Army Quartermaster Museum |date=January 1949 |title=Conference Notes prepared for the Quartermaster General }} many historical references support the claim that the K-ration was indeed named after him.{{cite journal | title = Olaf Mickelsen (July 29, 1912 to August 8, 1999) | journal = Journal of Nutrition | year = 2001 | first = Rachel | last = Schemmel |author2=Simin Vaghefi |author3=Barbara Bowman | volume = 131 | issue = 2 | pages = 205–210| pmid = 11160534 | quote = During World War II, I worked with Dr. Ancel Keys on the K ration. This emergency ration was named after Dr. Keys because of the pioneering work he did in getting our country conscious of the fact that a ration of this type would be surely needed if we became embroiled in war.| doi = 10.1093/jn/131.2.205 | doi-access = free }} The K-ration became such a success that it was often used for more than temporary sustenance, becoming a major staple of military nutrition.

{{main|Minnesota Starvation Experiment}}

During World War II, Keys produced various studies related to human physical performance that were of interest to the military, such as studying the effects of testosterone on muscle work{{cite journal | title = Influence of Methyl Testosterone on Muscular Work and Creatine Metabolism in Normal Young Men | journal = Journal of Clinical Endocrinology and Metabolism | first = Leo | last = Samuels |author2=Austin Henschel |author3=Ancel Keys | volume = 2 | issue = 11 | pages = 649–654 | year = 1942| doi = 10.1210/jcem-2-11-649 |url=http://jcem.endojournals.org/cgi/content/abstract/2/11/649 | access-date = February 6, 2011| url-access = subscription }} and vitamin supplementation as a performance enhancer on adequately fed soldiers,{{cite journal | title = The performance of normal young men on controlled thiamine intakes | journal = Journal of Clinical Nutrition | year = 1943 | first = Ancel | last = Keys |author2=Austin Henschel |author3=Olaf Mickelsen |author4=Josef Brozek | volume = 26 | issue = 4 | pages = 399–415|url=http://jn.nutrition.org/cgi/reprint/26/4/399.pdf | access-date = February 6, 2011}}{{cite journal | title = Vitamin supplementation of US Army rations in relation to fatigue and the ability to do muscular work | journal = Journal of Clinical Nutrition | year = 1942 | first = Ancel | last = Keys |author2=Austin Henschel | volume = 23 | issue = 3 | pages = 259–269|url=http://jn.nutrition.org/cgi/reprint/23/3/259.pdf | access-date = February 6, 2011}} among many other similar studies. It was during the war that Keys and fellow researchers recognized the importance of knowing how to properly treat widespread starvation, since simple overfeeding for so many would be imprecise and there was a potential that the refeeding would fail.

To gain insight into the physiology of starvation, in 1944 Keys carried out a starvation study with 36 conscientious objectors as test subjects in the Minnesota Starvation Experiment. At the time, conscientious objectors were being placed in virtual concentration camps, with a few functioning like the Civilian Public Service, so that recruiting them would prove easier than seeking out volunteers in the general population. The original pool of 400 responders was reduced to 36 selectees, of whom 32 would go on to complete the study.{{cite book | last1 = Keys | first1 = Ancel | author-link1 = Ancel Keys | title = The Biology of Human Starvation | publisher = University of Minnesota Press | year = 1950 | location = Minneapolis | pages = 262}} The main focus of the study was threefold: set a metabolic baseline for three months, study the physical and mental effects of starvation on the volunteers for six months, and then study the physical and mental effects of different refeeding protocols on them for three months. The participants would first be placed on the three-month baseline diet of 3200 calories after which their calories were reduced to 1800 calories/day while expending 3000 calories in activities such as walking. The final three months were a refeeding period where the volunteers were divided into four groups, each receiving a different caloric intake.

The war came to an end before the final results of the study could be published, but Keys sent his findings to various international relief agencies throughout Europe and, by 1950, he completed publication of his two-volume 1385-page Biology of Human Starvation.

{{Main|Seven Countries Study}}

His interest in diet and cardiovascular disease (CVD) was prompted, in part, by seemingly counter-intuitive data: American business executives, presumably among the best-fed people, had high rates of heart disease, while in post-war Europe CVD rates had decreased sharply in the wake of reduced food supplies. Keys postulated a correlation between cholesterol levels and CVD and initiated a study of Minnesota businessmen (the first prospective study of CVD).{{cite journal |vauthors=Keys A, Taylor HL, Blackburn H, Brozek J, Anderson JT, Simonson E |title=Coronary heart disease among Minnesota business and professional men followed 15 years |journal=Circulation |volume=28 |issue= 3|pages=381–395 |date=September 1, 1963|pmid=14059458 |doi=10.1161/01.cir.28.3.381|doi-access=free }} At a 1955 expert meeting at the World Health Organization in Geneva, Keys presented his diet-lipid-heart disease hypothesis.{{cite web|title=Famous Polemics on Diet-Heart Theory|author=Henry Blackburn|publisher= School of Public Health, University of Minnesota|url=http://www.epi.umn.edu/cvdepi/essay.asp?id=33|archive-url=https://web.archive.org/web/20140327233831/http://www.epi.umn.edu/cvdepi/essay.asp?id=33|archive-date=March 27, 2014}}{{cite book | last = Keys | first = Ancel| title = Seven Countries: A Multivariate Analysis of Death and Coronary Heart Disease |url=https://archive.org/details/sevencountriesmu0000keys | url-access = registration | publisher = Harvard University Press | year = 1980 | isbn = 978-0-674-80237-7 }} As part of his argument, he presented a correlation between deaths from heart disease and percentage of fat in the diet that featured six countries.{{Cite journal|last=Keys|first=A.|date=July 1953|title=Atherosclerosis: a problem in newer public health|journal=Journal of the Mount Sinai Hospital, New York|volume=20|issue=2|pages=118–139|issn=0099-9695|pmid=13085148}} His rationale and conclusions were heavily critiqued by two other epidemiologists.{{Cite journal|last1=Yerushalmy|first1=J.|last2=Hilleboe|first2=H. E.|date=July 15, 1957|title=Fat in the diet and mortality from heart disease; a methodologic note|journal=New York State Journal of Medicine|volume=57|issue=14|pages=2343–2354|issn=0028-7628|pmid=13441073}}

After observing in southern Italy the highest concentration of centenarians in the world, Keys hypothesized that a Mediterranean-style diet low in animal fat protected against heart disease and that a diet high in animal fats led to heart disease. This finding helped Keys initiate a long-term observational study, known as the Seven Countries Study, which appeared to show that serum cholesterol was strongly related to coronary heart disease mortality both at the population and individual levels.Kromhout D: "Serum cholesterol in cross-cultural perspective. The Seven-Countries Study". Acta Cardiol 1999;54:155–158Katan MB, Beynen AC. "Linoleic acid consumption and coronary heart disease in U.S.A. and U.K." Lancet. 1981 Aug 15;2(8242):371

Keys had concluded that saturated fats as found in milk and meat have adverse effects, while unsaturated fats found in vegetable oils had beneficial effects. Keys stated that of the 12,000 men in seven countries studied in 1960, those least likely to develop cardiovascular disease lived in Crete.[http://www.nytimes.com/1998/02/10/science/personal-health-pass-the-wine-and-olive-oil-and-other-lessons-from-crete.html "Personal Health; Pass the Wine and Olive Oil, and Other Lessons From Crete"]. nytimes.com. Retrieved May 4, 2024.

After Keys' retirement from the University of Minnesota in 1972, his protege Henry Blackburn, MD became director of the Laboratory of Physiological Hygiene.{{cite web |title=Blackburn, Henry « Heart Attack Prevention |url=http://www.epi.umn.edu/cvdepi/bio-sketch/blackburn-henry/ |website=University of Minnesota |access-date=March 28, 2020}} Blackburn continued research on the role of lifestyle including diet in the cause and prevention of heart disease. The department played an active role in multicenter trials of the 1970s–80s and population strategies of surveillance and preventive interventions in Minnesota.

The Keys equation predicts the effect of saturated and polyunsaturated fatty acids in the diet on serum cholesterol levels. Keys found that saturated fats increase total and LDL cholesterol twice as much as polyunsaturated fats lower them.{{cite web|url=https://www.lipid.org/sites/default/files/images/mwall/Ancel_Keys.pdf|title=Ancel Keys, PhD (1904–2004)|publisher=National Lipid Association|access-date=August 15, 2016}}

File:Eat Well Stay Well 1963.png

When Keys was hired at the Mayo Foundation in 1936, he hired Margaret Haney (1909–2006) as a medical technologist. In 1939 they married and had three children: Carrie D'Andrea, Henry Keys, and Martha McLain.{{cite news | first = Ben | last = Cohen | title = Chemist, author, diet researcher Margaret Keys was 97 | date = December 18, 2006 |url=http://www.startribune.com/obituaries/11603901.html | work = Star Tribune | access-date = February 6, 2011 | archive-url=https://web.archive.org/web/20111208163753/http://www.startribune.com/obituaries/11603901.html | archive-date = December 8, 2011 }} Carrie became a clinical psychologist and Henry became a physician and cancer researcher. Both are well respected contributors to their fields. Martha was shot dead by a thief in 1991 when she was 42.{{cite book|page=211|last=Tucker, Todd|publisher=University of Minnesota Press|isbn=978-0-8166-5161-0|first=2006 Simon & Schuster|year=2007|title=The Great Starvation Experiment: Ancel Keys and the Men Who Starved for Science}}

Together, Margaret and Keys co-authored three books, two of them bestsellers. They earned enough royalties to build Minnelea, their villa in the seaside village of Pioppi, in the Cilento region on the southwest coast of Italy, where Keys lived and worked from 1963 to 1998.Tucker 2006. p. 207.{{cite web |title=Ancel Keys |url=https://www.theflorentine.net/2011/06/01/ancel-keys/ |publisher=The Florentine |date=June 1, 2011 |access-date=May 2, 2021}} They also traveled the world, going to places like Japan and South Africa to record data for Keys's published works, such as the Seven Countries Study. The village of Pioppi became the location of the Living Museum of the Mediterranean Diet, which houses a documentary, photograph and film archive regarding the historic, scientific, and cultural background of the Mediterranean diet.{{cite web |title=Living Museum of the Mediterranean Diet |url=https://tenutaducamarigliano.it/en-gb/portfolio-item/living-museum-mediterranean-diet/ |publisher=Tenuta Duca Marigliano |access-date=May 2, 2021}}

Keys appeared on the To Tell The Truth game show as the inventor of K-Rations, fooling two of the four panelists.{{cite web |title=To Tell The Truth |url=https://www.youtube.com/watch?v=1MDpFyhm_lk | archive-url=https://ghostarchive.org/varchive/youtube/20211211/1MDpFyhm_lk| archive-date=December 11, 2021 | url-status=live|website=You Tube | date=February 29, 2016 |publisher=CBS Television |access-date=August 19, 2019}}{{cbignore}}

Keys received three notable awards: Commander, Order of the Lion of Finland (1963), the McCollum Award from the American Society of Clinical Nutrition (1967), and an honorary doctor of science from the University of Minnesota (2001).{{cite web|title=Ancel Keys, MS, PhD|url=http://www.epi.umn.edu/cvdepi/bio-sketch/keys-ancel/|publisher=Regents of the University of Minnesota|access-date=January 9, 2019}}

On January 26, 2004, Keys celebrated his 100th birthday.

Keys died on November 20, 2004, in Minneapolis, two months before his 101st birthday.{{cite press release|title=Ancel Keys. |url=http://www.the-aps.org/membership/obituaries/ancel_keys.htm |publisher=The American Physiological Society |year=2004 |access-date=November 13, 2007 |archive-url=https://web.archive.org/web/20070927031550/http://www.the-aps.org/membership/obituaries/ancel_keys.htm |archive-date=September 27, 2007 }}{{cite news|last1=Brody|first1=Jane E. |title=Dr. Ancel Keys, 100, Promoter of Mediterranean Diet, Dies|url=https://www.nytimes.com/2004/11/23/obituaries/dr-ancel-keys-100-promoter-of-mediterranean-diet-dies.html|work= The New York Times|date= November 23, 2004|access-date= July 28, 2016}}

Keys was an atheist.{{cite book|title=The Great Starvation Experiment: Ancel Keys and the Men Who Starved for Science|year=2008|publisher=U of Minnesota Press|isbn=978-0-8166-5161-0|author=Todd Tucker|page=146|quote=Max's advocates made up a diverse cast of characters, from the Jewish Peace Fellowship leader Rabbi Isador Hoffman to the atheist Ancel Keys, who wrote the committee that Max "proved to be a highly reliable and conscientious man who comported himself well under the most rigorous and demanding circumstances."}}

Keys has received criticism from the low-carbohydrate diet community, who have argued that his Seven Countries Study excluded countries that did not fit his hypothesis.{{cite journal |author=Pett, Katherine D |author2=Willett, Walter C |author3=Vartiainen, Erkki |author4=Katz, David L|year=2017|title=The Seven Countries Study|journal= European Heart Journal|url=|volume=38|issue=42|pages=3119–3121|doi=10.1093/eurheartj/ehx603|pmid=29121230|doi-access=free}}{{citation|title=Ancel Keys and the Seven Countries Study: An Evidence-based Response to Revisionist Histories|last1=Pett |first1=K D |last2=Kahn |first2=J |last3= Willett |first3=W C |last4= Katz |first4=DL|year=2017|url=https://www.truehealthinitiative.org/wp-content/uploads/2017/07/SCS-White-Paper.THI_.8-1-17.pdf|publisher=True Health Initiative |access-date=August 29, 2018}} Critics raised four primary objections to the Seven Countries Study, including (1) countries were selected and excluded based on a desired outcome; (2) France, a high-fat, low-heart disease country, was purposefully excluded from the survey; (3) dietary data in Greece taken during Lent introduced a distortion; and (4) sugar was not considered as a possible contributor to coronary heart disease. In response to this criticism, on August 1, 2017, the True Health Initiative released a 65-page white paper entitled "Ancel Keys and the Seven Countries Study: An Evidence-based Response to Revisionist Histories," correcting what they felt were historical inaccuracies and errors that low-carb advocates had perpetuated.Pett, Kahn, Willett & Katz (2017) p 22, 32, 37, 43

• {{cite book|last1=Keys|first1=A.|last2=Brozek|first2=J.|last3=Henschel|first3=A.|last4=Mickelsen|first4=O.|last5=Taylor|first5=H. L.|title=The Biology of Human Starvation (2 volumes)|publisher=University of Minnesota Press|year=1950| isbn = 978-0-8166-7234-9}}
• {{cite book|author-mask=1|last1=Keys|first1=Ancel|last2=Keys|first2=Margaret|title=Eat Well and Stay Well|publisher=Doubleday|year=1959|lccn=59-6361}}
• {{cite book|author-mask=1|last1=Keys|first1=Ancel|last2=Keys|first2=Margaret|title=The Benevolent Bean|url=https://archive.org/details/benevolentbean00keys|url-access=registration|publisher=Doubleday|year=1967|lccn=67-12853}}
• {{cite book|author-mask=1|last1=Keys|first1=Ancel|last2=Keys|first2=Margaret|title=How to Eat Well and Stay Well the Mediterranean Way|publisher=Doubleday|year=1975|isbn=978-0-385-00906-5}}
• {{cite book|author-mask=1|last1=Keys|first1=Ancel|title=Seven Countries: A Multivariate Analysis of Death and Coronary Heart Disease |url=https://archive.org/details/sevencountriesmu0000keys|url-access=registration|publisher=Harvard University Press|year=1980|isbn=978-0-674-49788-7}}
• {{cite book|author-mask=1|last=Keys|first=Ancel|title=Adventures of a Medical Scientist: Sixty Years of Research in Thirteen Countries|year=1999|publisher=memoir, privately published | isbn = 978-0-9672072-0-9}}

{{CDC|article=Morbidity and Mortality Weekly Report|url=https://www.cdc.gov/mmwr/preview/mmwrhtml/mm4830a1box.htm}}

{{Reflist|30em}}

• {{commons category-inline}}
• [https://www.sevencountriesstudy.com/about-the-study/investigators/ancel-keys/ "Ancel Keys"] at Seven Countries Study
• {{cite web|url=http://mbbnet.umn.edu/firsts/blackburn_h.html|title=Ancel Keys|access-date=April 15, 2007|author=Blackburn, Henry|publisher=University of Minnesota}}

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{{DEFAULTSORT:Keys, Ancel}}

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Category:Mediterranean diet advocates

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