Researcher Robert Schneider, MD, says those results should apply to the general population. Schneider is director of the Institute for Natural Medicine and Prevention at the Maharishi University of Management (MUM) in Fairfield, Iowa.
"This taps into a universal physical phenomenon that is not related to race, age, culture, etc.," Schneider says. "This state of restful alertness has restorative benefits for everyone. It's a way to utilize the body's own internal pharmacy."
TM is a trademarked form of meditation. It requires training by a certified teacher to "settle inward" to a place called "transcendental consciousness." The technique is one of the two pillars underlying education at the Maharishi University of Management, according to the school's web site.
Health Benefits of TM
The study was a collaboration between MUM and the Medical College of Wisconsin in Milwaukee. Researchers recruited 201 African-American men and women whose average age was 59 and who were generally considered obese.
All of the participants previously had been diagnosed with heart disease. Many of them were current smokers. African-Americans, says Schneider, have a 35% higher risk of dying from heart disease than the general population.
The people in the study were divided into two groups. While both groups continued to receive standard care and medication for heart disease, the study group attended a seven-step course in TM. The people in that group were then instructed to meditate twice a day for 20 minutes for the duration of the study.
Schneider says that the program was standard for TM practitioners and had not been modified for the study.
The comparison group received conventional health education. The people in that group were told to spend at least 20 minutes a day on heart-healthy activities.
Members of both groups were followed for as long as nine years.
Anger control and overall anger also improved. Those who entered the study with either high blood pressure or high stress benefited the most from meditation.
The TM group was expected to meditate 14 times per week. But the researchers found that on average participants only practiced the technique 8.5 times.
They would have done well to stick to their instructions. Those who followed the study guidelines more strictly, Schneider says, had even greater benefits. Their risk reduction was 66%.
"In cardiology, we are always impressed when we see any effective intervention," says cardiologist Michael Shapiro, DO, of Oregon Health and Science University in Portland. "But to actually show a reduction in overall mortality -- that is really impressive."
Shapiro, who reviewed the study for WebMD, says that its design appears scientifically rigorous and that its results are likely valid. But he says the study was too small to draw any definite conclusions.
"I am enthusiastic and cautiously optimistic," says Shapiro. "Overall, I like the study, and it provides justification for a much larger study."
Shapiro, who practices a different form of meditation, also says that more needs to be learned about what drives these results. He says the reduction in blood pressure, while significant, is likely not enough to account for all of the study's positive outcomes.
"Meditation can do a whole host of positive things: reduce anger and stress, encourage happiness," he says. "Who is to say that these are not the most important factors? This study can't get at the mechanism involved. We don't know how it works."
A Cost-Effective Means of Prevention
Transcendental Meditation, says Schneider, is "a simple, effortless, and natural way to settle down to a quiet state of mind."
But it is not free. According to the Maharishi Foundation USA's web site, the seven-part introductory TM course that the study participants attended costs $1,500. Financial aid and sliding scale fees are available to those who can't afford the full amount.
To Schneider, this study shows that TM is a cost-effective means of prevention.
"This is the strongest study ever done on meditation or any mind-body intervention for cardiovascular disease," he says.
In July 2011, the study was pulled from publication in Archives of Internal Medicine, a last-minute decision made when one of the journal's reviewers raised questions about the data. Schneider says that in the intervening time, the data was re-analyzed. Also, new data was added and the study underwent an independent review.
"This is the new and improved version," Schneider says. It appears in the current issue of Circulation: Cardiovascular Quality and Outcomes.