NEW Defend Your Life II, the updated version of the award-winning Defend Your Life, offers lots of new vitamin D information. Get the latest vitamin D research. Discover vitamin D's role in preconception through early childhood. Author Susan Rex Ryan examines how adequate vitamin D supplementation may decrease your risk of developing medical conditions including autoimmune diseases, bone conditions, and cancer. And, of course, the popular Vitamin D Wellness protocol is included in Defend Your Life II