There you are, locked in an interview with your prospective employer. Things are going well enough when all of sudden the urge to break wind becomes unbearable. Rather than ask to be momentarily excused you decide to try and tough it out but sooner rather than later nature fulfills her destiny and the unmistakable sound and accompanying odor infiltrate the room.
Rather than ask the interviewer something asinine like “Did you hear that?” or “What's that smell?” you sit there in stunned silence. The interviewer just glares at you and soon you feel your face getting warm and then your cheeks begin to get hot. You are embarrassed and rightly so. You start to turn a deep shade of crimson and you just can’t make it stop.
Not to worry my soon to be dismissed friend, the symptoms that just occurred are all natural to us humans and each and every one of us blushes at one time or another in our lives. We are also unique in that experience as no other animal seems to blush or suffer from embarrassment.
The act of blushing from embarrassment is involuntary and cannot be controlled. It’s triggered by something called the sympathetic nervous system, the same system that controls our fight or flight response when dealing with stressful situations.
It seems that when we become embarrassed our adrenal glands go into overdrive and release adrenaline. This causes our blood vessels to dilate and the flow of blood to your face to increase. Since the veins in your face are relatively closer to your skin than in other parts of your body, the face becomes noticeably redder.
Before you ask, the answer is yes. Black people blush too.
Thus far, science can’t determine why some people are more subject to fits of blushing than others but they are looking into it. Some theories are that humans blush to try and garner empathy after committing one or more type of faux pas. Blushing acts as a physical way of saying “I’m sorry” to those that might have been offended and might generate a bit of sympathy your way.
One should not confuse blushing with flushing. Flushing might occur when somebody has had too much to drink, is in the throes of passion and/or is mightily pissed off at something or someone. In fact, even though the symptoms such as the reddening of the face are the same, the triggers appear to be direct opposites.
In closing, hopefully I haven’t embarrassed myself or even worse, you readers by trying to write this.
Source(s)
My first real job interview and http://tlc.howstuffworks.com/family/blush1.htm