Loking How Meditation May Work

Practicing meditation has been shown to induce some changes in the body, such as changes in the body's "fight or flight" response. The system responsible for this response is the autonomic nervous system (sometimes called the involuntary nervous system). It regulates many organs and muscles, including functions such as the heartbeat, sweating, breathing, and digestion, and does so automatically.

The autonomic nervous system is divided into two major parts:

• The sympathetic nervous system helps mobilize the body for action. When a person is under stress, it produces the fight-or-flight response: the heart rate and breathing rate go up, for example, the blood vessels narrow (restricting the flow of blood), and muscles tighten.
  
  
• The parasympathetic nervous system creates what some call the "rest and digest" response. This system's responses oppose those of the sympathetic nervous system. For example, it causes the heart rate and breathing rate to slow down, the blood vessels to dilate (improving blood flow), and activity to increase in many parts of the digestive tract.
  
  

While scientists are studying whether meditation may afford meaningful health benefits, they are also looking at how it may do so. One way some types of meditation might work is by reducing activity in the sympathetic nervous system and increasing activity in the parasympathetic nervous system.

Scientific research is using sophisticated tools to learn more about what goes on in the brain and the rest of the body during meditation, and diseases or conditions for which meditation might be useful. There is still much to learn in these areas. One avenue of research is looking at whether meditation is associated with significant changes in brain function. A number of researchers believe that these changes account for many of meditation's effects.

Side Effects and Risks

Meditation is generally safe. There have been a small number of reports that intensive meditation could cause or worsen symptoms in people who have certain psychiatric problems, but this question has not been fully researched. Individuals who are aware of an underlying psychiatric disorder and want to start meditation should speak with a mental health professional before doing so.

Any person who is interested in using meditation as CAM should consider the following:

• Meditation should never delay the time it takes you to see your health care provider about having a medical problem diagnosed or treated, and it should not be used as the only treatment without first consulting your provider.
• Tell your health care providers about any complementary and alternative practices you use. Give them a full picture of what you do to manage your health. This will help ensure coordinated and safe care.
• If you are interested in learning meditation, ask about the training and experience of the instructor (see also NCCAM's pdf publication "Selecting a CAM Practitioner").
• Find out whether there have been any research studies published on meditation for the health condition you are interested in.

• What Meditation Is
• Meditation For Health Purposes
• NCCAM's Meditation Full Overview Brochure (pdf)
  
• Learn About Yoga