The effects of stress

John Denninger has spent most of the last five years studying the centuries-old disciplines of yoga and meditation but with a new twist. Denninger, a Harvard Medical School psychiatrist, is using modern genetic technologies to track changes in the body that occur when highly stressed individuals engage in the ancient traditions for just a few minutes a day. One source of the stress he's hoping to tame is infertility.

A separate Harvard study estimates 60% to 90% of all doctor visits in the U.S. are stress-related; common causes of stress include infertility, depression, hypertension, and aging. The World Health Organization estimates indicate that stressed-out employees cost American businesses $300 billion or more each year due to absenteeism, low production levels, and high turnover rates.

Mind-body connection in stress

Denninger's interest in the mind-body connection was sparked when, as a foreign exchange student the summer before he started college, he discovered tai chi in China. He devoted every morning for three weeks to master the ancient martial art under the direction of a tai chi master. Denninger says that the experience got the message "through my thick teenage skull that there was something very important about the breath and about inhabiting the present moment." He's carried that message forward into the medical research he does today.

In his current study, Denninger is working with 210 healthy adults who experience high levels of chronic stress that lasts six months or more. The study participants are divided into three groups:

• 70 spend 20 minutes a day performing Kundalini yoga
• 70 spend 20 minutes a day meditating
• 70 spend 20 minutes listening to audiobooks on stress education

Each study participant completes his or her daily stress-reduction exercise at home. Kundalini yoga combines several stress-relieving elements: breathing, meditation, postures, and the singing of mantras. Denninger chose this form of yoga for its emphasis on meditation.

Study results

At the beginning of the study, participants came once a week for two months to Denninger's lab where they were given instructions on their assigned discipline. While there, blood samples were taken and neuro-imaging tests were run. At three intervals during the study, more blood and neuroimaging tests are done and the participant completes a questionnaire. The five-year study concludes in 2015.

Thus far, the Denninger study has found a positive stress-reducing effect at the molecular level after just the first session, even among novices to their assigned discipline. Genes that involve insulin secretion and energy metabolism are getting activated while genes that provoke stress and the inflammatory response are getting turned off. The Kundalini group experienced the best benefits.

Source: Kitamura, Makiko. "Harvard yoga scientists find proof of meditation benefit." Harvard Medical School News. The President and Fellows of Harvard College. Nov 21, 2013. Web. Mar 26, 2014.