(26) And God said, “Let us make humans in our image, after our likeness."
(6) Whoever sheds the blood of a person, By a person shall their blood be shed; For in God's own image were humans created.
(9) But take utmost care and watch yourselves scrupulously...
Bava Kamma 90b
Rabbi Akiva said, "A person is not permitted to harm him/herself."
Maimonides, Mishneh Torah, Hilchot Deot, 3:3
One should aim to maintain physical health and rigor, in order that the soul may be upright, in a condition to know God.
Christian Reference:
Romans 12:1 - I beseech you therefore, brethren, by the mercies of God, that ye present your bodies a living sacrifice, holy, acceptable unto God, which is your reasonable service.
Muslim Reference:
Q'uran 82:5-7 - O man! What has enticed you from your gracious Lord who has created and well-proportioned you, and given you a perfect moulding?