Prolongs

Chastity prolongs youth.

The happiness of a person prolongs his day.

Laughter prolongs life.

By the way, I found out from Yahoo's scientific newsletter that hugging regularly strengthens one's health and prolongs one's life.

Healthy food prolongs your life.

Vacuum packaging consists of rigid or flexible containers from which substantially all air has been removed before sealing. Carbon dioxide or nitrogen may be introduced into the container. This process prolongs shelf life, preserves the flavors and retards bacterial growth.