WEDNESDAY, July 2 (HealthDay News) -- Researchers say they've taken a significant stride forward in understanding how relaxation techniques such as meditation, prayer and yoga improve health: by changing patterns of gene activity that affect how the body responds to stress.

The changes were seen both in long-term practitioners and in newer recruits, the scientists said.

"It's not all in your head," said Dr. Herbert Benson, president emeritus of the Benson-Henry Institute for Mind/Body Medicine at Massachusetts General Hospital and an associate professor of medicine at Harvard Medical School. "What we have found is that when you evoke the relaxation response, the very genes that are turned on or off by stress are turned the other way. The mind can actively turn on and turn off genes. The mind is not separated from the body."

One outside expert agreed.

"It's sort of like reverse thinking: If you can wreak havoc on yourself with lifestyle choices, for example, [in a way that] causes expression of latent genetic manifestations in the negative, then the reverse should hold true," said Dr. Gerry Leisman, director of the F.R. Carrick Institute for Clinical Ergonomics, Rehabilitation and Applied Neuroscience at Leeds Metropolitan University in the U.K.