Before she steps out of her car and into her office each workday morning, Colleen Cannon takes a minute or two to notice her breath. She doesn't have respiratory problems, work anxiety or a fascination with seeing her breath vapor on cold winter days. It's just that since she took a course called "Mindfulness-Based Stress Reduction," she now realizes the difference a breath can make.

Cannon's new habit helps her step back and live in the moment. "It puts me more in my body rather than just in my mind," the Chanhassen resident said. "When I'm aware of my body, it puts enough distance between me and all the worries of the mind, and that makes it easier for me to tackle them."

As Cannon has experienced, breathing has the potential to improve a person's outlook and well-being. It may also improve some aspects of physical health, mental awareness, emotions and mood.

But isn't breathing supposed to be automatic, something we don't have to think about, like our heartbeat?

The answer is yes, but people also develop breathing habits, and those patterns can range from helpful to detrimental. Breathing techniques, commonly practiced in yoga, meditation and other Eastern traditions, may slow the heart rate and lower blood pressure. Studies on the breathing and meditation methods that Cannon learned indicate that the practice helps with some medical symptoms, chronic disorders, stress reduction and psychological issues such as anxiety and depression.

Breathing in brings oxygen to our red blood cells, which then carry oxygen to all our cells, including our heart and brain, so they can function properly. Breathing out removes the carbon dioxide that our bodies produce, said Dr. David Ingbar, director of the pulmonary medicine division at the University of Minnesota.

The most efficient breath uses the diaphragm, a midsection muscle that descends with the intake of breath, pushing the contents of the belly out of the way and expanding the belly outward. Breathing this way is called diaphragmatic breathing, or belly breathing. The diaphragm is the respiratory workhorse, designed to handle breathing all day, every day. People also have a "helper" in the accessory muscles of the upper chest, but chest breathing is "more stressful and less efficient," Ingbar said.

Unless someone needs to use both the belly and chest to breathe -- for instance, if they're working out or have asthma -- it's best to breathe with the belly.

However, "many people aren't breathing optimally," said Terry Pearson, a pharmacist who is also a Mindfulness-Based Stress Reduction instructor at the University of Minnesota's Center for Spirituality and Healing. Babies and children naturally breathe from their bellies, but adults dealing with the stress and the fast pace of modern life might fall into a habit of taking shallow, rapid breaths, she said.

The same thing can happen for people preparing for an important or nerve-racking event, like a public speech, Pearson said. Such fast, shallow breathing can create a domino effect because the person can feel the effects of less oxygen, such as being lightheaded, and start to get anxious, which can lead to hyperventilation.

Fortunately, there's hope for people who want to change this habit and start the New Year off on a calmer note or for people who are prone to stressed breathing due to crowded shopping mall parking lots, long airport security lines or upcoming family gatherings. When people make a habit of simply noticing, feeling or observing their breath they can improve their well-being and reduce stress, Pearson said. "We feel the stability and centeredness of the body and this calms us," she said.

It also gives people a stopping moment to realize that they can choose how they react instead of living on autopilot, she said. In a way, it's about making a habit of the adage, "Take three deep breaths and count to 10 before you say something when you're angry."

Our breath is also a mirror, reflecting what's going on in our bodies and minds, said Mark Nunberg, a meditation teacher at Common Ground Meditation Center in Minneapolis. "It's easier to directly work with the breath than to work with the mind because the mind is more subtle," he said. "If we can cultivate easy breathing, our minds become a little less restricted and less reactive."

Focusing on the breath can help people let go of unhelpful habits, such as neurotic or obsessive thinking. "In order for the mind to be fully aware of the breath, it has to let go of all its self-centered dramas," he said. "And that is healing."

Sarah Moran is a Minneapolis-based freelance health writer.