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Benedict, Francis Gano

Benedict, Francis Gano

(b. Milwaukee, Wisconsin, 3 October 1870; d. Machiasport, Maine, 14 May 1957)

chemistry, physiology.

Washington Gano Benedict, a businessman, and Harriet Emily Barrett were average middle-class parents with secondary-school backgrounds. They moved in 1881 to Boston, where Francis attended public high school. He studied the piano and his parents planned a musical career for him. Meanwhile, he dabbled in his basement chemical laboratory.

Upon graduation (1888), Benedict devoted a year to the study of chemistry at the Massachusetts College of Pharmacy. He continued at Harvard University and received a B.A. (1893) and M.A. (1894) in chemistry. An additional year at Heidelberg under Professor Victor Meyer led to the Ph.D., magna came laude. On his return Benedict assisted W. O. Atwater at Wesleyan University, where he became lecturer in chemistry in 1905 and professor in 1907. He supplemented his income through research as a chemist at the Storrs Agricultural Experimental Station (1896–1900) and as physiological chemist for the Department of Agriculture (1895–1907).

Atwater transformed Benedict from a chemist into the world’s foremost expert on animal calorimetry and respiratory gas analysis. Benedict applied his mechanical skill to improvement of the apparatus used in these studies and the establishment of rigorous experimental controls.1 William Welch and John Shaw Billings were impressed with Benedict’s early publications on animal heat and metabolism, and they convinced the Carnegie Foundation trustees to establish a nutrition laboratory under Benedict’s direction.2 The result was the Boston Nutrition Laboratory, where Benedict remained until his retirement (1907–1937).

Benedict the man was straightforward and eminently Victorian. His marriage in 1897 to a third cousin, Cornelia Golay, provided Benedict with a research assistant and eventually a daughter. He was against alcohol, trade unions, and the “decline” of culture. His friendships and professional associations were largely European. Magic tricks and the piano were his hobbies. He equated science with progress and “the spirit of service” to humanity.3

Benedict’s European affiliations were the result of his chosen field of research. The study of metabolism through calorimetry and the analysis of body intake and output was developed in the nineteenth century and was still current in Europe. In 1897, when Benedict joined him, Atwater prepared an exhaustive compilation of European contributions to the technique.4 Atwater and Benedict confirmed the validity of energy conservation in animal metabolism.

The concept “metabolism” was radically changing in the early decades of the twentieth century.5 The keys to energy transformation clearly lay within the emerging theories of hormonal control, catalysis, enzyme chemistry, and the vitamins. Yet Benedict continued in the classic methods, perhaps because of his chemical rather than biological training. His acknowledgment of the newer methods shows neither enthusiasm nor personal conviction.6

Benedict took care to distinguish between an organism’s loss of heat and production of heat. He began with the basic assumption that all animal tissue produces heat to the same degree (calories per kilogram body weight per unit time). He tested the assumption through extensive comparisons of various cold-and warm-blooded animals and searched for extremes to prove his point. The newborn, the young, the elderly, the obese, the thin, the dieter, the vegetarian, patients with overactive thyroids or one lung, diabetics, the tiniest mouse, even the elephant, came under his scrutiny. By 1910 he realized that organisms do not produce heat in any simple, mechanical fashion. Large animals produced greater amounts of heat but small animals yielded more heat per unit of body weight. He remained steadfast, however, in the belief that homeostasis was maintained by heat loss, not heat production.7 Accurate data were his driving passion, and comparative physiology provided the basis for his judgments.

He established criteria of comparison for the variable rates of metabolism that he found: sex, age, condition, water content, and the idea that “active protoplasmic mass” differed from total body weight. Two standards of judging metabolic rates were available to him: the relation to body surface area and to body weight. Benedict unequivocally favored the latter.

His most important contribution was the invention of an apparatus to measure simultaneously, directly, and accurately oxygen consumption, expired air, and heat (1924). His respirator provided the foundation for the basal metabolic-rate test, which has only recently given ground to less involved methods. His standards for the basal metabolic rates of humans are still valuable (1919). Insensible perspiration was found proportional to basal metabolism and body weight (1926), variations in the temperature of anatomical structures were mapped out (1911), lipogenesis investigated, and the caloric values of foods established. Diabetics were thought to have a low metabolic rate. Benedict revised clinical treatment of these patients by demonstrating that their metabolic rate was higher than normal (1910).

He was a member of the National Academy of Sciences (1914), American Philosophical Society (1910), American Academy of Arts and Sciences (1930), Society of American Magicians (1930), and honorary member of medical and scientific societies across Europe. He received the National Institute of Social Sciences medal in 1917 (for his work on the alcohol problem), the gold honor medal of the University of Hamburg in 1929 (physiology), and was given an honorary M.D. by the University of Würzburg in 1932.


1. The best descriptions of his methods and apparatus are found in Benedict and Carpenter (1910), Benedict and Talbot (1914), and Benedict and Burger, Abderhalden’s Handbuch, Abt. 4 (1924).

2. DuBois and Riddle, p. 69.

3. Commencement address given at the University of Maine, 9 June 1924; repr. in Science, n.s., 60 (1924), 209, 212–213.

4. W.O. Atwater and C.F. Langworthy. A Digest of Metabolism Experiments in which the Balance of Income and Outgo was Determined, bull. no. 45. U.S.D.A. Office of Expermental Stations (Washington, 1897).

5. See O. Folin, “A Theory of Protein Metabolism,” in American Journal of Physiology, 13 (1905), 117–133; Russell Chittenden, The Nutrition of Man (New York, 1907). Benedict was aware of the changes: Atwater and Benedict (1899), p. 6, and the latter’s work on creatinine (1907).

6. Benedict and Talbot (1921), p. 1; Benedict, Lectures on Nutrition (1925), pp. 17, 20; Benedict (1938), p. 200; DuBois and Riddle, pp. 73–74.

7. Benedict (1938), pp. 203, 212.


1. Original Works. Benedict published extensively, A list drawn up by E. DuBois and O. Riddle (see below) should be consulted. W. O. Atwater and Benedict joint publications are not included. They are as follows: Experiments on the Metabolism of Matter and Energy in the Human Body, bull. no. 69, U.S.D.A. Office of Experimental Stations (Washington, 1899); Experiments on the Metabolism of Matter and Energy in the Human Body, 1898–1900, bull. no. 109 (Washington, 1902); Experiments on the Metabolism of Matter and Energy in the Human Body, 1900–1902, bull. no. 136 (Washington, 1903).

II. Secondary Works. O. Riddle, “Francis Gano Benedict (1870–1957),” in The American Philosophical Society Yearbook, 1957 (Philadelphia, 1958), pp. 109–113; E.F. DuBois and O. Riddle, “Francis Gano Benedict,” in Biographical Memoris. National Academy of Sciences, 32 (1958), 66–98.

Charles A. Culotta

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Benedict, Francis Gano

Benedict, Francis Gano >(1870–1957) American nutritionist; developed the spirometer used to determine oxygen consumption and measure metabolic rate.

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"Benedict, Francis Gano." A Dictionary of Food and Nutrition. . 21 Aug. 2017 <>.

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