I have been thinking quite a bit about anger and it's impact on mental, emotional, and physical health. In the crowded culture in which we live anger poses a double problem. First, with so many different ways that we interact there are bound to be multiple exposures to things that can make us angry. But the second problem is that in our culture anger is not very well accepted or received. Most of us probably experience some kind of anger and most of us play polite and rarely "go off on" someone, especially if they are not related to us.
Anger is a powerful emotion. It is quite easy for anger to kick in the adrenal's fight-flight reaction -- our blood pressure rises, heart rates increase, the mouth dries out, muscles tighten, eyes dilate, breathing increases, and digestion comes to a screeching halt. Staying angry for a long period of time can create substantial wear and tear on us physically. Anger is a central emotion contributing to the negative effects of stress.
Anger is a secondary emotion. This means that anger occurs as a response to some other emotion. The primary emotion that gives rise to anger is usually hurt or suffering, although fear is also common. Hurt feelings generate a lot of anger. We live in a society that seems to find a great deal of pleasure out of hurting others' feelings as a humor artform. With the laughter that comes from some slam or insult, anger arises; but because others are laughing at our expense, we often have little we can do or say. So anger stays bottled up inside. Refusing to participate in rude and/or insulting humor certainly could make the world a better place in which to live.
There are a number of ways to handle anger. It's often best and easiest to try and evaluate what the hurt or fear was that caused us to get angry. This is the classic "count to ten" approach. Once you know why you're angry, then speak to the person who may have caused the hurt or fear about that, rather than exploding about how angry you were. Anger often begets anger. An excellent resource I came across in a bookstore just by accident (serendipity?) is a book entitled simply Anger, by Thich Nhat Hanh. I have been using the breathing technique taught in this book for a month or more now and find that it's helping me to stay centered and grounded in many different circumstances, not solely with anger. Breathing is so important, and it definitely helps to calm down all the physical responses to strong emotion, as well as calming the mind and spirit as well. I encourage you to try it, I think you'll find it helpful in your life journey as well.