The nose has a left and a right side; we use both to inhale and exhale.
Actually they are different; you would be able to feel the difference. The right side represents the sun, left side represents the moon.
Right side belongs to ‘hot’, so it gets heated up easily, left side belongs to ‘cold’. Most females breathe with their left noses, so they get “cooled off” faster. Most of the guys breathe with their right noses, they get worked up.
Also something useful, Yoga helps to recover from headache and to get refreshed … …
During a headache, try to close your right nose and use your left nose to breathe.
In about 5 mins, your headache will go. If you feel tired, just reverse, close your left nose and breathe through your right nose. After a while, you will feel your mind is refreshed.