Research suggests that when we make acts of kindness a habit, it's also good for our health. Whether it's volunteering at a local food bank, or taking soup to a sick neighbor, there's lots of evidence that when we help others, it can boost our own happiness and psychological well-being. But there's also growing research that it boosts our physical health too, says Tara Gruenewald, a psychologist at Chapman University.

Perhaps the most striking evidence comes from the Baltimore Experience Corps trial, a large experiment in which adults age 60 and older were randomly assigned to either volunteer at elementary schools or be put on a waiting list. The volunteers spent at least 15 hours a week tutoring underprivileged kids. After two years, the researchers found that the volunteers had measurable changes in their brain health.

One of the researchers said, "They didn't experience declines in memory and executive function like we saw in our control participants. And there were even changes in brain volume in areas of the brain that support these different cognitive processes.” Volunteers were also more physically active, "which is important for maintaining both cognitive and physical health as folks age.”

Another researcher added, "Volunteering or doing an act of kindness can distract you from some of the problems that you might be having, so you might be a little bit less reactive yourself. And "it may help to give you more perspective on what your own problems are." Also, when you go out to help others, it also makes you more physically active and less lonely. Social isolation is a known risk factor for physical and mental health problems, especially as we age.

At the very least, volunteering will make the world a little bit better place for many others. And we might just make it a little bit better for ourselves.