"I am the Lord who heals you," Exodus 15:26.
Exodus 23:25-26 "So you shall serve the Lord your God, and He will bless your bread and your water. And I will take sickness away from the midst of you. No one shall suffer miscarriage or be barren in your land; I will fulfill the number of your days."
God desires for us to have "whole-life" in our body.
And John also expressed the will of God when he wrote "Beloved, I pray that you may prosper and be in health as your soul prospers" 3 John 2.