How meditation works
Research has shown that meditation induces changes in your autonomic nervous system that alter the body's natural "fight-or-flight" response. The autonomic nervous system has two parts. The sympathetic nervous system is the one that produces the fight-or-flight response in reaction to stress -- and the result is that the blood vessels narrow, muscles tighten, breathing quickens, heart rate rises, and the body is flooded with stress hormones such as cortisol. The parasympathetic nervous system does just the opposite: When it's activated, the blood vessels dilate, breathing slows down, and heart rate falls. Meditation is thought to reduce the activity of the sympathetic nervous system and increase the activity of the parasympathetic nervous system.

Meditation and your health
"Meditation can have a phenomenal effect on your health," says Sood. "When you are able to bring yourself to that relaxed state, it reduces blood pressure, pulse rate, cortisol release, decreases insulin release and improves immune function." There's even evidence that it might affect the body on a genetic level. "There may be chromosomal activity that can affect longevity," he says.

And, of course, there's the benefit of relaxation. "Stress has a tunneling effect on your awareness, so when you are stressed, you can't function as well and make good decisions," explains Sood. But when you practice using meditation to achieve a more relaxed state, your ability to focus can increase; as a result, you might find that you are more productive, have more patience, think before you act, and generally enjoy a smoother day. Regular practice can help you sidestep the fight-or-flight response when it's not really warranted. "We need that response when there is a genuine threat, but we don't need it all the time," says Sood. "It's like the airbags in your car -- you need them in case of emergency, but you can't drive around with them always deployed."

Meditation how-to's
There isn't one "correct" way to meditate. But, according to Sood, there are two basic types of secular meditation: concentrative meditation, in which you sit quietly and focus on a key phrase or on your breathing; and mindfulness meditation, a sort of "meditation-lite" that involves staying present and nonjudgmental throughout the day. Sood recommends starting with mindfulness to help you start to learn how to shift your attention and focus before jumping into the more intense, concentrative type.

Mindfulness meditation
The key here is to engage with your experiences and stay in the present. Ideally, it is a state you can maintain -- at least to some degree -- throughout the day. To start, Sood recommends this exercise immediately upon waking to set the tone for your day: Before you even get out of bed, remember to feel gratitude -- for your partner sleeping next to you, for the warm carpet under your feet, for the sun shining in the window. Then, for the next 45 minutes or so, really focus on enjoying and engaging with your experiences -- the feeling of the hot water in the shower, the smell of the coffee brewing, the taste of your breakfast. "If you can pay attention to your experiences for just a moment more than normal, you are being present and accepting in a non-judging way," says Sood.

Concentrative meditation
Sit or lie down somewhere comfortable, close your eyes and start to focus on your breathing. Concentrate on slowly inhaling and exhaling through your nose. If you like, you can repeat a meaningful word or phrase to help focus your attention. It is normal for your attention to wander. Don't try to suppress thoughts that come into your head; just gently return your focus to your breathing or repeated word without judging yourself. Maintain this practice for 10 to 15 minutes before gently opening your eyes and returning to your day.