Gary Cohen, Co-Founder and President of Health Care Without Harm, received a 2015 MacArthur genius grant. (John D. & Catherine T. MacArthur Foundation)

Health environmentalist Gary Cohen was at a reception for social entrepreneurs in the spring when someone from the MacArthur "genius" fellowships program sat down next to him. He remembered telling her how important it was to raise awareness about the impact of environment on health. He described his decades of work. She nodded politely.

Cohen kept her card in his office. "I prayed deeply that something might transpire from this," he said in an interview Tuesday from his home in Boston.

As it turned out, Cecilia Conrad was a plant. The MacArthur Foundation had already picked him as one of its 2015 grant recipients, and Conrad, managing director of the fellows program, was doing reconnaissance. She confessed as much when she contacted him recently with the good news: "She said, 'I was purposely sitting next to you to check you out.'"

[Here's the list of this year's MacArthur "genius" grants ]

Cohen runs Health Care Without Harm, an organization he co-founded in 1996. It advocates for health-care corporations and hospital systems to become ecologically sustainable in the face of climate change. The nonprofit is headquartered in Reston, Va., but has offices around the world.

The group of fellows includes two other health experts: Lorenz Studer, a stem cell biologist who is working on Parkinson's disease, and Beth Stevens, a neuroscientist working on how the brain's wiring develops during childhood into early adulthood.

Cohen was stunned when he got the foundation's call. "I just thought it was such an honor and validation not only for my work, but the work of the organization and the people who built the social movement inside of health care that has now taken root," he said.

In what he labels a "coming-to-Jesus" moment, Americans now recognize that the nation spends more money on health care than any other country on the planet, and yet often has worse health.

"Everybody is seeing that, and it creates an opportunity in health care to re-evaluate what we're doing," Cohen said. That means hospital executives and others are more willing to address fundamental issues that make people sick in the first place, such as poor housing, poor food and a polluted environment.

Lorenz Studer, a stem-cell biologist working on Parkinson's disease at Memorial Sloan Kettering Labs in New York City, is a MacArthur genius grant recipient. (John D. and Catherine T. MacArthur Foundation)

Hundreds of hospitals around the country are now using their purchasing power to support local farmers, which benefits their employees, patients and the local economy, he said. In California, his organization is working with 55 hospitals and five school systems to link their combined purchasing clout.

There's also been a big change in hospitals' attitudes on climate change.

"Three years ago, you couldn't talk about it," Cohen recalled. But hospitals and health systems now are realizing they can lock in better energy pricing by using renewable sources and "that's happening in a dramatic way." The organization has created a health-care climate council, with participation from 15 of the country's largest hospital systems, which represent 400 facilities.

Cohen said he's not sure what he'll do with his $625,000 MacArthur grant, which he'll receive in four, no-strings-attached installments. He'd like to support a medical clinic in Bhopal, India that provides free care to survivors of the Union Carbide pesticide plant explosion. His 17-year-old daughter, Asha Densmore, jokingly offered a different suggestion: paying for college.

Yet he's also considering his first sabbatical in 20 years. He would like to go to Italy for a few months with his wife, Carol Densmore, and "think about the next phase of our transformative work."

Beth Stevens, Assistant Professor of Neurology at Children's Hospital in Boston, received a MacArthur genius grant. (John D. and Catherine T. MacArthur Foundation)

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