WHEN stressed or anxious, a common coping mechanism is to take a deep breath.
But a scientist has claimed this could be the wrong approach, and make your symptoms worse.
Neuroscientist and Stanford professor Dr Andrew Huberman explained the “breathe in through the nose and out through the mouth” method could increase your heart rate.
On a recent episode of Mayim Bialik's Breakdown podcast, he said: "If somebody is stressed, or if you are stressed, taking a deep breath is not the best solution.
“If you just take a deep breath, actually you will increase your heart rate through a process called respiratory sinus arrhythmia."
Dr Huberman said the best and fastest way to regulate stress in real time is to breathe through your nose twice.


He suggested taking a double inhale through the nose, and a long, extended exhale through the nose.
“It’s not a hack - this is what you do when you are in a claustrophobic environment and you do it every one to three minutes during sleep,” Dr Huberman said.
When a person is not breathing enough, the tiny sacs of the lungs, called alveoli, “collapse and flatten out like empty balloons”.
The consequence is that you don’t get enough oxygen into the bloodstream, and instead “carbon dioxide builds up, and if you’re stressed this happens even more”.
The podcaster explained that when doing a double inhale, it helps the alveoli to properly inflate.
“When you do that, you naturally activate the neural circuits in the brain and body that shift that seesaw from sympathetic (alertness and stress) to parasympathetic,” he said.
The sympathetic and parasympathetic nervous systems make up the autonomic nervous system.
While the sympathetic nervous system activates the fight or flight response, the parasympathetic nervous system restores the body to a state of calm.
“For most people it takes only one so-called physiological sigh - double inhale through the nose, long full exhale through the lungs - to completely return to a calm state,” Dr Huberman said.
“This is, as far as I know, the fastest way to shift your way from stressed to calm.”
Dr Huberman said some people struggle or fail to breathe through their nose enough day-to-day, and mouth breathing is linked to health problems.
The nose is a better filter for viruses and bacteria than the mouth, therefore may prevent illness.
Dr Zac Turner, a medical practitioner in Australia, told the website news.com.au in July: “The beauty of your nose is that it’s perfectly designed to breathe safely.
“It can filter out foreign particles due to its nasal hairs. It can humidify inhaled air which makes it easier for your lungs to use, and it produces nitric oxide which is a vasodilator.
“That’s just a scientific way of saying it widens blood vessels to help improve oxygen circulation in your body.
“Your mouth is perfectly designed to eat, drink and talk, but it doesn’t have any of the nifty features your nose has.”
Dr Turner said to improve your nose breathing and lung efficiency, try exercises like alternate nostril breathing, belly breathing, and Breath of Fire.
“These techniques may help you master nose breathing while enhancing your lung function and reducing stress,” he said.