Practicing spirituality rightly one can increase body immunity to infinity. Something totally unheard of but it was an absolute reality of spiritual life.
When seekers indulged in spirituality they not only controlled their sexual inhibitions but also multifold desires and wishes growing rapidly within. Demolition of ego in stages results in growth of a healthy body. In absence of desires and wishes, the stresses and strains on the body reduced heavily. This resulted in spiritual travelers maintaining a healthy body.
If someone was suffering from cancer, it is quite possible that practicing spirituality rightly one can eradicate all symptoms of cancer from the body. Spirituality reduces the clutter in our thought process and cancer was all about all clumsy thoughts collecting together. If we minutely observe we would find all suffering from cancer had a very erratic thought pattern, no goal in life.
The moment thoughts get organized indulging in spirituality; our body cleaned itself of all parasitic, dead cells that were no longer required in the body. A pure thought process leads to a healthy lifestyle. For travelers of spiritual path eradication of diseases like cancer, mental problems is not only a possibility but definitely happened.
Furthermore spirituality advocates indulgence in asanas (yogic exercises), a daily routine indulging in which the body maintains itself fit and fine.
I have personally observed that for a period exceeding 20 years I was not affected by any viral fever. The moment negativity crept into my thinking process; I suffered bouts of viral fever after a very long period of time. Again by moulding my thought process, I am experiencing robust health.
A totally negative thought process is the cause of most illnesses in the body. The moment we changed our outlook from negative to positive, everything changed in our life for better.
And this is truly what spirituality is all about. While maintaining a healthy body, a positive thought process, seekers truly reached God in their lifetime.