Pray that your husband will understand the importance of taking care of his body--the temple of the Holy Spirit--for the glory of God. Pray that he will practice self-control by making wise food choices, and get sufficient exercise to stay healthy.
Romans 12:1-2 I appeal to you therefore, brothers, by the mercies of God, to present your bodies as a living sacrifice, holy and acceptable to God, which is your spiritual worship. Do not be conformed to this world, but be transformed by the renewal of your mind, that by testing you may discern what is the will of God, what is good and acceptable and perfect.
1 Corinthians 6:19-20 Or do you not know that your body is a temple of the Holy Spirit within you, whom you have from God? You are not your own, for you were bought with a price. So glorify God in your body.
1 Corinthians 9:27- But I discipline my body and keep it under control, lest after preaching to others I myself should be disqualified.
Resource: Revive Our Hearts