WHY does shame turn cheeks red?

 The feeling of shame is stressful to the human body. Adrenaline is created during times of stress. It is a hormone that enters the picture and actively participates in the "fight or flight" choice. We adopt a defensive stance out of worry, as if we were defending ourselves.

Adrenaline primes the body to deal with danger by accelerating breathing, heart rate, and pupil size to take in as much visual data as possible. Vascular dilation occurs as circulation increases. Due to its smaller thickness than the rest of the body, the skin on the face is the first to become red.