They say true peace comes from within. The philosophical maxim may actually have science on its side, if an upcoming study from Carnegie Mellon University is anything to go by. Not only does mindfulness meditation lower your perceived stress level. Your brain starts producing different chemicals, too.

People bristle at the idea of meditation for a number of reasons, perhaps the most outstanding ones being the perceived time commitment and the steep learning curve that comes with it. Meditation takes years, people tend to assume, because they believe meditation can only be performed by masters. And mastery takes years.

The latest research fights back. It says all a person needs to reduce his or her stress levels is 25 minutes a day for three consecutive days. A chemical analysis of 66 healthy individuals’ saliva and questionnaires asking about their emotional state revealed that keeping a mindful, meditative state causes cortisol levels to come tumbling down. Cortisol is the hormone scientists often refer to as the “stress hormone.”

Lead author of the study J. David Creswell, associate professor of psychology, said the research was meant to peel back the layers of mystery surrounding meditation. "More and more people report using meditation practices for stress reduction,” he said in a statement, “but we know very little about how much you need to do for stress reduction and health benefits.”

Along with the group of subjects who learned meditation through a brief training course, where they practiced breathing techniques and staying present in the moment, another group was busy at work completing a three-day cognitive skills program. The group analyzed poetry in an effort to build problem-solving skills. At the end of the three days, both groups faced a stern-faced panel of evaluators. Subjects completed rigorous verbal and mathematical tests.

Afterward, Creswell and his colleagues collected saliva samples and asked participants how stressed out they felt during the tests. In the end, both measures revealed the same result. The mindful meditators were less stressed after the tests than the poetry group, evidenced by both their reported feelings and the cortisol levels found in their saliva. This doesn’t disprove the possibility of a placebo outright. It’s possible the meditation group believed they would de-stress, so they felt more at ease, lowering their cortisol levels. But the researchers believe the opposite happened: Meditation lowered cortisol levels directly, and subjects felt more relaxed as an effect.

Creswell concedes the practice may not have an immediate effect for everyone. "When you initially learn mindfulness meditation practices, you have to cognitively work at it — especially during a stressful task,” he said. People may try to achieve a meditative state but manage only to stress themselves out more. This is why it’s helpful, he says, to practice meditation when it doesn’t need to serve an immediate purpose.

Meditation has been found in prior research to reduce inflammation. Many of these practitioners, however, are expert meditators. Science has long sought to understand what goes on in the brains of people who achieve true meditative states, as they’re often described as euphoric, or approaching nirvana. Much of the mysteries, unfortunately, have yet to be solved.