There is a lot to know about prana. The breath is connected to neuro-physiology. When the left nostril is dominating, the right side of the brain is active. When the right nostril is functioning, the left side of the brain (logic, thinking and understanding) is active. When the breath predominantly goes in and out through the right nostril and very little through the left nostril, is when knowledge permeates. When the breath predominately goes in and out through the left nostril, you listen and enjoy without understanding the knowledge, like it is music. When the breath flows equally through both nostrils, meditation and prayer happen. Or nothing happens.

If you come to meet a guru, or pass by a temple, a church, a place of worship or spiritual activity, you will find both nostrils are equally functioning.

Prana, or life force, moves through the nostrils where there are three nadis. The sun nadi is the right nostril. The moon nadi is the left nostril. The fire nadi is in-between both. This is known as the Sushumna nadi. We are living in an ocean of prana. Prana and Truth, or consciousness, is the prana of prana. 

The five types of prana in the body are Prana, Apana, Udana, Samana and Vyana.

Prana is the energy in the upper part of the body, in the region above the heart. If prana is too high or is imbalanced you cannot sleep.

Apana Vayu is the energy in the lower part of the body. If Apana is too high, then you feel lethargic, sleepy, and dull.

Samana Vayu is in the stomach region, it aids digestion.

Udana Vayu is in the upper chest and throat region, it is responsible for emotions. If Udana Vayu is imbalanced, you have no emotions, you become like a stone or you become so mushy-mushy and weak.

Vyana is all over the body, it is responsible for movements in the joints, the circulation in the body. If Vyana Prana is disturbed, then the circulatory system is disturbed, your joints are not flexible, there are aches and pains.

Panch Prana, the five different types of prana are present in everybody, and different pranas dominates at different times. The imbalances in the pranas are corrected during Pranayama and Sudarshan Kriya.

To understand prana takes a long time.There are 172,000 nadis or prana channels which function in our body.

The breath changes with every action, and certain prana functions at certain times.The Vedas teach us that the metabolism of your body is twice when you are breathing through the right nostril than it is when breathing through the left. Following this, when the left nostril is functioning, it is a good time to drink; when the right is functioning, then it is a good time to eat. If you do the reverse, then within six months time you may fall sick. Ayurveda also says that you should not eat and drink at the same time, and when you do eat you should leave a gap of half an hour to an hour before drinking. The nadis, the breath, changes every hour. Similarly, prana changes, the energy in the world changes, all the time.