We are told by the Psalmist that our bodies are "fearfully and wonderfully made" (Psalm 139).  Paul also states in 1 Corinthians 6:18-20 that our bodies are temples of the Holy Spirit.  If this is true, we have an obligation to take care of our temple, in a similar way to how God has laid out in His system in the Bible.  If He cared so much about a temple made of stones and lumber, which are not alive, how much more must He care for you and I that He has given life and life more abundantly (John 10:9-11).