The root cause of all diseases is one or the other kind of uncleanliness which breeds germs or bacteria. A Yoga Sadhaka i.e., a student of Yoga consequently starts with ‘Shaucha’ or cleanliness. Internal and external, physical and mental cleanliness comes under ‘Shaucha’.
Text books on Yoga lay down various practices for cleaning different parts of the body. But we are, however, concerned here with the cleanliness of the nose only. If the nose is kept clean and healthy a cold cannot successfully attack the person even inspite of the conditions of infection being present.
Any organ – teeth, eyes, ears, skin, bowels, etc. is liable to fall prey to a disease if not cleansed regularly. The teeth, eyes, skin and others fortunately receive our due attention in this direction, but the nose generally remains neglected, though it is the most important organ and on its health depends the well being not only of the lungs, ears and eyes but of the whole system. This is the organ through which we suck in the ‘Prana-Vayu’ i.e. life-breath. This should be invariably cleansed every morning along with the teeth.
Ordinarily, whatever dust is inhaled lodges on the mucous surface of the nasal canal and is pushed towards the outer orifice by the minute cilia which are in constant outward motion. Any microbes entering the nose are likewise expelled, and in addition to this mechanical expulsion, the nasal mucous which by nature is germicidal destroys a large number of bacteria. But with the amount of dust we inhale and the adulterated food and poisonous drinks we are daily swallowing, clogging of the whole physical mechanism in unavoidable. The nasal passage accordingly suffers from dust accumulation and stuffing. Handkerchiefs cannot remove all the dust and mucous accumulated from the long zigzag nasal passage, and the refuse begins to encrust.