Why friends are as important to health as diet and exercise

Friendship has profound implications for our understanding of what humans and animals need to thrive across a lifetime. Science reporter and author of “Friendship: The Evolution, Biology, and Extraordinary Power of Life’s Fundamental Bond” Lydia Denworth tracks the biological, psychological, and evolutionary foundations of friendship. KCRW’s Jonathan Bastian talks with Denworth about how friendship can change how healthy we are and why the bonds of kinship are often more significant than those of marriage.