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The Physicians Committee

Ulka Agarwal, M.D., and Neal Barnard, M.D., check neurological function.

Zeroing in on Human Health: PCRM’s Clinical Research

Diabetes and prediabetes affect an enormous number of people around the globe, including more than 100 million Americans. Alzheimer’s disease affects nearly half of people by age 85. Cancer remains a major threat. Chronic pain is a challenge for millions. To tackle these diseases and many more, it is clear that we need enlightened research. But how shall we go about it?

We can draw some inspiration from President John F. Kennedy. Facing the prospect of Soviet domination in space in 1961, President Kennedy set as a national goal of “landing a man on the moon and returning him safely to Earth,” and called for it to be achieved within a decade. Whether reaching the moon was a worthy goal or not, the method used to achieve it is what counts. President Kennedy did not dole out a series of grants—a few thousand here, a million there—to anyone who had an idea for how to launch a rocket. Rather, the project was delegated to NASA, which followed a single-minded strategy. And on July 20, 1969, Neil Armstrong set his boots on the lunar surface.

Medical research is very different. It tends to use a scattershot approach, moving in many unrelated directions, often using a variety of animal “models” that may or may not apply to the human condition. For now, the end of diabetes, Alzheimer’s, and cancer remain as distant as the moon in 1961.

Like the space race, research needs to follow a logical trajectory from launch pad to target. Research on heart disease provides a useful model. First, large population studies, such as the Framingham Heart Study, identified the risk factors for heart disease—high cholesterol levels, smoking, obesity, hypertension, and others. Next, intervention studies tested ways of changing these risk factors, showing that, indeed, stopping smoking, reducing blood pressure and cholesterol, and exercising could prevent heart attacks and even reverse heart disease. Although there were many distractions along the way, including a baboon heart transplant into a human baby, various experimental medical devices that never made it to market, and countless drugs that crashed and burned, research that followed the sequence from human population studies to intervention trials paid off.

Diabetes research has lagged behind. Although the first step—solid population studies—has been largely fulfilled, showing that obesity, meaty diets, and other factors lead to type 2 diabetes, research on changing these risk factors has been slow in coming. There have been a few exemplary studies, such as the Diabetes Prevention Program, which showed that diet and exercise could prevent diabetes even more powerfully than medications. But many intervention studies are needed to show how to solve the problem population-wide.

Similar considerations apply for Alzheimer’s disease. Population studies have shown that dietary factors may play as decisive a role in Alzheimer’s disease as they do in heart disease or diabetes, but studies putting those findings to the test have been few and far between.

The Physicians Committee’s Clinical Research

In the late 1990s, PCRM was approached by a private diabetes foundation that had wearied of requests to fund experiments on rats and mice, and instead was interested in funding research with humans. The Diabetes Action Research and Education Foundation provided a grant to PCRM to conduct a pilot study of the effect of a plant-based diet on type 2 diabetes. Prior studies had shown that populations following largely plant-based diets had low rates of obesity and diabetes; it made sense to put the diet to the test in people diagnosed with the disease. As it turned out, the project was very successful. Participants lost weight and greatly improved their blood sugars. Other PCRM studies followed, showing that plant-based diets reliably cause weight loss and improve insulin sensitivity, which are key factors in diabetes, as well as dramatically reducing cholesterol levels.

Predicated on this success, the National Institutes of Health awarded PCRM a grant in 2003 to conduct a larger test of a plant-based diet as a treatment for type 2 diabetes, comparing it head-to-head with the dietary recommendations of the American Diabetes Association. Competition for NIH funding is intense, of course. But PCRM had a solid research plan, it had tested the plan in pilot studies, and it had a team of experienced researchers.

The study quickly bore fruit. It showed that a plant-based diet improved blood sugar control, body weight, and cholesterol more effectively than a conventional “diabetes diet” could. The reduction in the key indicator of blood sugar control, hemoglobin A1c, was three times greater with the plant-based diet, compared with a diet based on American Diabetes Association guidelines—greater even than typical oral diabetes medications. The diet itself turned out to be well-accepted by the participants, many of whom lost substantial amounts of weight, reduced their medication use, and felt better than they had in years.

The results were published by the American Diabetes Association in its journal Diabetes Care, the American Journal of Clinical Nutrition, the Journal of the American Dietetic Association, and in other leading journals, and were presented at key scientific conferences, leading to their incorporation in the official policy documents of the American Diabetes Association and the Academy of Nutrition and Dietetics.

The next step was to test the approach in a wider audience. To do this, PCRM worked with the Government Employees Insurance Company (GEICO). The first GEICO study included company offices in Chevy Chase, Md., and Fredericksburg, Va. The second test included GEICO offices in 10 cities across the United States. Once again, participants lost weight, diabetes improved, and cholesterol levels fell. These findings were published in four peer-reviewed medical journals. The studies proved that the intervention could work, not only in a Washington, D.C., research center, but right where people live and work. These studies led to the incorporation of plant-based nutrition programs at the Potomac Electric Power Company (PEPCO), Capital One bank, SanDisk, and many other companies.

Along the way, the research findings turned into a book published by Rodale and influenced many other books and articles. A man in Detroit who tried the approach found dramatic improvements in his diabetes and suggested to Detroit Public Television that it consider a television program on vegan diets for diabetes. This became a Public Broadcasting System program that debuted in 2010 and aired in local PBS markets more than 6,000 times. People began to use the diet approach with great success and word spread to more and more people.

These research efforts have drawn on prior investigations that established risk factors in large populations, and aimed to develop methods to prevent illness and reverse it to the extent possible.

The Research Team

Clinical research is complex and requires a team effort. The Physicians Committee’s research programs are headed by Ulka Agarwal, M.D., chief medical officer and director of clinical research. Anne Bunner, Ph.D., Francesca Valente, Rosendo Flores, Joseph Gonzales, R.D., Jill Eckart, C.H.H.C., Mallory Huff, and Susan Levin, M.S., R.D., coordinate the studies, teach classes, and keep participants on track, and many other PCRM staffers keep the gears of research turning.

The Physicians Committee is currently conducting a 28-week study examining the effects of diet changes on painful neuropathy, a serious complication of long-standing diabetes. The team is also testing a dietary intervention that can be used by clinicians in the practice setting. Two other studies tackle the pain of rheumatoid arthritis and migraines. Medications play an important role in the management of these potentially debilitating conditions, but are limited in effectiveness and often have side effects. Dietary interventions have appeared promising in investigations carried out by numerous research teams, but most have been small and poorly controlled. PCRM’s research aims to develop and test practical interventions that can be used by doctors and patients.

PCRM also conducts detailed reviews of the scientific literature, including meta-analyses. Current studies are reviewing the evidence on nutrition’s role in weight disorders, Alzheimer’s disease, migraine, and diabetes. 

In conducting its studies, the Physicians Committee has often partnered with other institutions, notably the George Washington University School of Medicine, Georgetown University School of Medicine, and the University of Toronto, and works with scientific consultants from a variety of research centers.


Good Medicine Summer 2013

Good Medicine
Summer 2013
Vol. XXII, No. 3

Good Medicine

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