05/27/2026
We are honored to announce this year’s awardees of the Hellen Linkswiler Graduate Student Scholarship. Dr. Hellen M. Linkswiler was one of the pioneering women in nutrition research. She served as a SPAR in the U.S. Coast Guard Women's Reserve from 1944 to 1946. Although she rarely talked to students or colleagues of her early experiences, she did tell one graduate student that she supervised the baking of hundreds of pies per day as a dietitian in the military.
After the SPARS, she began graduate studies at the University of Wisconsin in the Department of Foods and Nutrition. Both her masters and doctoral research focused on vitamin B-6 metabolism. In 1946, she earned an M.S. in Food and Nutrition under the direction of May Reynolds. In 1951, she earned a Ph.D. with a joint major in Food and Nutrition and Biochemistry. May Reynolds and Carl Baumann were co-advisors for her doctoral research.
From 1951 to 1954, she was an associate professor in the Department of Food and Nutrition at the University of Alabama. From 1954 to 1960, she was a Professor in Foods and Nutrition at the University of Nebraska. There she was involved in a series of studies that examined the availability of various amino acids to humans from foods, especially corn. Hellen's first work on human mineral requirements was also done at Nebraska.
In 1960, Hellen returned to the University of Wisconsin-Madison as a Professor in the Department of Foods and Nutrition in the School of Home Economics. Hellen became one of the founding members of the Department of Nutritional Sciences in the College of Agricultural and Life Sciences in 1968. The new department included four faculty members from the Department of Food and Nutrition in the School of Home Economics, three faculty members from the College of Agricultural and Life Sciences, and one from the School of Medicine.
Her research after she returned to the University of Wisconsin focused on three areas. She continued the work that she began at the University of Nebraska on human amino acid requirements. In a series of studies, she and her students determined the optimal ratio of essential to nonessential amino acids in human diets and titrated the effect of energy intake on the amount of amino acids required to achieve nitrogen balance.
She also extended the work that she began on human vitamin B-6 metabolism as part of her own graduate studies. She and her students were the first to demonstrate that vitamin B-6 depletion could be identified by increased excretion of cystathionine and other methionine metabolites in urine (3). They worked with Jim Price's laboratory to extend the original observation by others on the importance of vitamin B-6 in the conversion of tryptophan into niacin. This basic biochemical work was crucial in developing sensitive ways to monitor nutritional status in regard to vitamin B-6 depletion. These tools were important in later studies in which she collaborated with Ray Brown and David Rose, as they assessed the impact of oral contraceptive on the vitamin B-6 requirements of women.
In 1970 Hellen, published the first of her articles on the effect of dietary protein intake on calcium utilization in humans (5). In this study, she and her students demonstrated that human subjects excreted twice as much calcium in urine when their dietary intake of protein was increased from 47 to 142 g/d. This work triggered scores of other studies and much controversy. Later investigators, who added “high protein” foods to diets, sometimes reported no change in urinary calcium excretion. They did not appreciate that Hellen had constructed elegantly controlled studies with real foods in which dietary levels of protein, calcium and phosphorus were meticulously controlled. Her students had incorporated isolated proteins into the bread that they baked and served to subjects.
After their initial observations, Hellen and her students patiently and methodically showed that the difference in results among different laboratories reflected that high protein foods (such as meat and milk) used in studies by other laboratories contained high level of phosphorus. The Linkswiler group systematically analyzed the physiologic mechanisms by which dietary protein increased urinary calcium excretion and dietary phosphorus decreased urinary calcium excretion. In the process, they demonstrated that 43% of the effect of dietary protein on urinary calcium excretion could be explained by the sulfur amino acid content of protein.
In her sixties (when many investigators are thinking of retirement), Hellen was still successfully competing for NIH grants. Her research had an effect far greater than simply protein, vitamin B-6 and calcium metabolism, i.e., she created models that have been used worldwide for studying bioavailability of nutrients in humans.
In total, Professor Linkswiler authored or coauthored more than 50 research manuscripts. This research was funded through USDA Hatch funds, USDA research and service contracts, and NIH grants. She was granted emeritus status at the University of Wisconsin in 1981.
