It is highly probable that you've heard someone say he is "stressed out." What does that mean? Exactly what is stress and how does it affect us? Read more about the causes of stress, what it does to us, and how to reduce stress.

A new study has found that a mother's arms are incredibly effective at reducing the physical symptoms of stress in crying babies. This article reports on the study and its implications. Includes a brief video. [1:56]