Imerman Angels, a cancer support organization based in Chicago, has "floods of volunteers," according to John May, chairman of its board of directors and a long-time volunteer himself.
"You can't help but just get excited to get involved," he said.
These do-gooders are not alone: The Bureau of Labor Statistics reported 63 million people volunteered in 2009, 1.6 million more than the year before. But the question of motive remains: Why is being nice so popular these days?
New research may unlock the mystery: Kindness is contagious, according to a study done by researchers at University of California, Los Angeles, and University of Cambridge and University of Plymouth in the United Kingdom.
When we see someone else help another person it gives us a good feeling, which in turn causes us to go out and do something altruistic ourselves, the study found, which was the first of its kind to systematically document this tendency in human nature.
"When you feel this sense of moral 'elevation' not only do you say you want to be a better person and help others," said Simone Schnall, of Cambridge, the lead researcher. "But you actually do when the opportunity presents itself."
Researchers performed two experiments in which they showed viewers either a nature documentary, a funny TV clip or an uplifting segment from the Oprah Winfrey Show, and then asked them to voluntarily help with another task. In both cases, participants that watched Oprah and subsequently experienced the elevated feeling were more likely to help.
"Elevation," a term coined by Thomas Jefferson, is different from regular happiness, a specific emotion that we experience only when we see someone else engaged in virtuous acts, Schnall said.
And though previous studies have documented this emotional response before, little research had been done to see if people actually acted on their feelings of being inspired, she said.
"Human nature is essentially good," she said. "And this study proves that seeing good things actually makes us better."
The best volunteers at Imerman Angels, which pairs up cancer survivors with people who are currently fighting the disease, are the ones who were first recipients of the program, May said.
After beating their cancer, "they realized the impact it had on their lives and want to share that," he said, adding all of the volunteers gain enthusiasm and energy from their experiences.
It is natural for us to seek the positive emotions that accompany seeing and doing acts of kindness, said Joseph Ferrari, professor of psychology at DePaul University. If we saw more positive stories in the media, it might spur an even greater trend of compassion, he said.
"If we had people reading about random acts of kindness it would spread and people would help more people," he said. "People want to be happy."
Alexander El Nabi, a junior at the University of Chicago, has volunteered since his freshman year. He attributes his desire to help others to mentors who have inspired him and the emphasis the university puts on giving back to the community.
He said he became heavily involved with Splash! Chicago, which runs programs for local high school students, after volunteering at an event and seeing "how beautiful the program was and how it was reaching out to kids that don't have opportunities like this."
"When they show people performing service they're showing you an opportunity," he said. "They're saying: 'You can do this service too.'"