The totality of our being is comprised of spirit, mind, and body. Therefore, an equilibrium must be achieved to maintain health, or achieve healing if one is sick. See Of Healing And Miracles.
To attain that necessary balance, the following steps are needed: a godly life that leads to repentance from sins; a harmonious family life; solid diet and hydration protocols; a sensible exercise regimen; a constant pursuit of knowledge; eight to ten hours of daily sleep; and scheduled times for socializing, relaxation (preferably outdoors under the sun, and even getting a pet is a good idea), and vacation to relieve stress.
Nevertheless, keep this in mind. God is no respecter of persons, therefore diseases will hit everyone, Christians or not. That’s because there is spiritual purpose in suffering and hardship.
“For whom the Lord loves he chastens, and scourges every son whom he receives.” Hebrews 12:6
In the end, strong health or full recovery or healing comes straight from the throne of God. He’s the one who decides if one’s efforts will take hold.
“I am the LORD who heals you.” Exodus 15:26
Consequently, the most important thing is to have faith in God and in Jesus whom He sent.
“And all things, whatsoever you shall ask in prayer, believing, you shall receive.” Matthew 21:22