O, The Oprah Magazine's Dr. David L. Katz talks about the relationship between nutrition and the immune system.

How your emotions affect your health and immune system.

Oprah Radio' host Dr. Mehmet Oz talks to neurosurgeon Dr. Kevin Tracey about how the brain and nervous system regulate the immune system.

As a Fox News war correspondent, Jennifer Griffin spent years covering conflict in the Middle East and was no stranger to war zones. But at age 40, she entered an entirely new battle when she was diagnosed with triple negative breast cancer.

Oprah Radio host Dr. Mehmet Oz talks with callers about boosting your child's immune system and if germs can be passed along on old clothing.