About 90% of all headaches are tension headachesAccording to the U.S. National Library of Medicine, tension headaches are the most common type of headache, and generally affect adults and adolescents - they can affect younger children, but this is not common.
During a tension headache, there may be muscle tightness in specific parts of the head, scalp and/or neck - these areas are uncomfortable and often painful. Some studies, however, have indicated that muscle tightness is not as common among sufferers as was once believed.
People who suffer from tension headaches say they feel like a tight band or vice on the head. The pain is usually dull, and covers most of the head.
It was thought that tension headaches were mainly caused by tension that builds up in the scalp and neck muscles as a result of stress, depression, anxiety, or a head injury. However, the exact cause or causes are unknown. Recent research indicates that there does not appear to be any significant increase in muscle tension in people known to suffer from tension headaches.
Experts today believe that a change in certain brain chemicals may be the main factors that contribute to tension headaches. These chemicals are the ones that help nerves communicate, such as serotonin, endorphins, and several others. We are not sure why the levels of these chemicals change. We suspect that the fluctuations activate pain pathways to the brain and probably undermine our ability to suppress pain.