God designed our corruptible physical bodies (earthly tents) to last so many years and then die. 
In many cases, we can improve the quality of our natural life, plus possibly extend it a few years by exercise and eating the right kind of food, especially raw vegetables. We can also nourish our bodies by taking vitamins, like C and D3, and drinking clean purified water. Especially avoiding toxins in food, water and the air are also a necessity.
Health and Nourishment Through the Spiritual
There is another important and major factor related to physical health, which will not be mentioned at the health food stores or at the doctor’s office! It is most important for our physical health and even more so for our spiritual health. The Bible says:
Do not be wise in your own eyes; fear the LORD and shun evil. This will bring health to your body and nourishment to your bones. (Prov 3:7,8)
Proverbs 3:7 describes Job, the most righteous man on the planet in his day like that (Job 1:1; 1:8; 2:3). Scripture goes on to say:
A cheerful heart is good medicine, but a crushed spirit dries up the bones. (Prov 17:22)
A man’s spirit sustains him in sickness, but a crushed spirit who can bear? (Prov 18:14)
A cheerful heart is a joyful and rejoicing heart. All Christians have at least two continuous reasons to rejoice:
However, do not rejoice that the spirits submit to you, but rejoice that your names are written in heaven. (Luke 10:20)
However, if you suffer as a Christian, do not be ashamed, but praise God that you bear that name. (1 Pet 4:16)
The opposite of a rejoicing heart is a sorrowful one which speeds up physical death:
Godly sorrow brings repentance that leads to salvation and leaves no regret, but worldly sorrow brings death. (2 Cor 7:10)
There are two types of sorrow, with one (worldly sorrow or crushed spirit) accelerating physical death and the other (godly sorrow) bringing forth repentance that leads to salvation (eternal life)! Again, the physical part of man is definitely influenced by other factors, which are not physical at all!
Nourish Your Physical Bodies Spiritually
In review at this point, to help yourself both physically and spiritually, be:
- Not wise in your own eyes
- Fearing the LORD
- Shunning evil
- Having a cheerful rejoicing heart
- Experiencing godly sorrow which brings forth repentance (turn from sins)
The Lord Jesus Is Most Important
To have the Lord Jesus resident within your physical body will make it the holy temple of God (1 Cor. 3:16,17), but that is not all.
Since Jesus himself is eternal life (1 John 1:2) and is the only means to find peace with God we read this:
In him was life, and that life was the light of men. (John 1:4)
Come to me, all you who are weary and burdened, and I will give you rest. Take my yoke upon you and learn from me, for I am gentle and humble in heart, and you will find rest for your souls. (Mat 11:28,29)
To prioritize the spiritual, with the Lord Jesus being at the top center, will avoid spiritual heart disease and a nightmarish eternity in hell after your inevitable death. Therefore, think nourishment, especially the kind which will extend throughout eternity!
