From the moment you came into this world, you've been breathing. And chances are pretty good that, in all that time, you haven't given the matter much thought. Our brains are clearly competent at controlling our lungs without any conscious effort on our part, so why would you?

In fact, according to a ton of reputable science, there are a great many reasons to be more deliberate about how you breathe. Learning to breathe correctly (which, in essence, amounts to more deeply) can lower your blood pressure, boost your immune system, clear your mind, fight the ill effects of stress, and even help you sleep better.

And in difficult times, it's particularly useful to know how to use your breath to keep yourself centered and calm. Studies show a few minutes of conscious deep breathing can have profound and positive effects on your state of mind

You've forgotten how to breathe.

Why don't we do this naturally? We all used to once. Watch a baby next time you get the chance and you'll see its round little belly rhythmically rising and falling as it inhales and exhales. But over time, many of us lose the "belly breathing" habit and begin shallower "chest breathing."

"Chronic stress can lead to a restriction of the connective and muscular tissue in the chest resulting in a decrease range of motion of the chest wall. Due to rapid more shallow breathing, the chest does not expand as much as it would with slower deeper breaths and much of the air exchange occurs at the top of the lung tissue towards the head. This results in 'chest' breathing," Psych Central explains.

Vanity may also play a part. "A 'washboard' stomach considered so attractive in our culture encourages men and women to constrict their stomach muscles. This adds to tension and anxiety, and gradually makes shallow 'chest breathing' feel normal," a Harvard Medical School explainer on the subject notes.

Making the most of your breath.

But just as many of us learn to chest breathe, we can also learn to breathe more deeply. "Most people can figure it out on their own from instructions or from watching a video," the Cleveland Clinic's Mladen Golubic tells WebMD.

So what are those basic instructions to start once again getting the full benefits of your breath?

  1. Figure out your current breathing pattern. To do this, just lie or sit in a relaxed way and put one hand on your upper chest and another just below the notch at the bottom of your ribs. Breathe deeply through your nose. If your bottom hand isn't moving much more than your top hand, you're breathing with your chest.
  2. Start breathing with your belly. Now, all you need to do is consciously make that lower hand rise more than that upper hand. Do that and you know you're breathing correctly.
  3. Slow your breathing. "Try to slow your breathing down to eight to ten cycles [one in and one out breathe] per minute without breathing from your upper chest area. Aim to breathe slowly and smoothly," suggests yoga teacher Fiona Agombar.

That's it. The basics breathing correctly truly are that simple. But there are plenty of (slightly) more elaborate breathing techniques such as alternate-nostril breathing you can learn to employ in a variety of situations. Read more about them in the WebMD and PsychCentral posts.