Want to live a longer life that is free from stress and sadness? You don't need any miracle drug to be able to do this. Medical doctors recommend a simple and fulfilling regimen: being generous.

Dr. Michael McKee, a psychologist at Cleveland Clinic, explained that generosity has a lot of benefits for a person's mental and physical well-being.

For instance, McKee said the practice of giving regularly time or material gifts to others can help relieve stress, which is known to cause various illnesses like hypertension and heart diseases.

"There are tremendous health benefits to giving. We know that the giving tends to reduce blood pressure, slow heart rate," the psychologist explained in an article on the CBN News website. "Again, giving reduces stress. It reduces depression."

McKee's statements about the health benefits of generosity are actually backed up by science. Studies separately done by researchers from the University of California and the University of Michigan have shown that sharing one's time can help prolong one's life.

The studies showed that older people who volunteered for two or more organisations were 44 percent less likely to die over a five-year period than those who didn't volunteer. These researchers accounted for other factors, including exercise and risky behaviours such as smoking.

Another research conducted by the National Institutes of Health using magnetic resonance imaging (MRI) also revealed better brain activity among persons who gave to charities.

This particular research showed that generosity stimulates the reward centre of the brain, triggering the release of chemicals that strengthen our immune system.

"There's a release of endorphins. These are the kinds of magical chemicals that come from various areas in the brain and they flood throughout the system," McKee explained.

"They're cousins, basically," he continued. "But some reduce pain, some seek out sick-looking cells and exert a healing effect on them. They have many different positive effects."

Dr. Stephen Deutsch, chairman of psychiatry at the Eastern Virginia Medical School, shared that generosity is also used to treat depression.

"We encourage people to not be so self-absorbed and to think about others," Deutsch said. "We even tell people to practice being concerned and invested in other people."