The intellect must be fed satsang (good thoughts from saints and scriptures) and the mind must be fed with good deeds. In the katha on Shri Pitamaha Bhishma, I have said that if your life is not filled with activities for a good purpose, you will catch illnesses.
I knew of an aged, respectable and healthy man. He had a disciplined routine in his life: a particular to wake up, have breakfast, catch the train, get to his shop to work, have dinner etc. His sons would tell him to stop working as they were responsibly looking after the business yet he would not stop his routine and work. This man was not a workaholic, but dedicated to his work, disciplined and 100% healthy.
Once the building with his shop caught fire and everything burnt down. His routine was messed and he became inactive. Consequently, a man who was free from diseases passed away within six months.
What I am trying to say here is that people who are dedicated to their work, in helping others and are creative live a long and healthy life.
I also know of a couple in Rajasthan who are doctors and have committed their life to one goal: service of people who are suffering and helpless in the society. They have committed not to have children so that they can fully dedicate themselves to this service.
Disease will not have a place in your life if you are busy with good work, a goal in life, engrossed in godly deeds and helping others.
All in all, you must feed good deeds to the mind. We must desire to live for 100 years as we perform good deeds.
Pitamaha Bhishma looked after his intellect as his daughter. He fed his daughter, the intellect, good values as she grew older and searched for a capable husband to marry her. He then offered and surrendered his intellect, which was pure and free from all worldly attachments through spiritual means, to Lord Krishna.
Pitamaha Bhishma said to Lord Krishna, “Dear Lord of Yadu clan, you are the only capable husband for my unmarried daughter, my intellect. Please marry and accept her”. The mind will purify with good deeds and such a mind signifies Vasudev. The intellect must be fed satsang and such an intellect signifies Devaki.
Let us all endeavour in this life to make our intellect worthy of Lord Krishna through good deeds, helping others and not sitting idle, and our mind through satsang.