Stress is a person’s physical and emotional response to change. Although most people tend to think of all stress as bad, it can be either positive or negative. An example of positive stress is having a new baby. The death of a loved one is an example of negative stress.

Stress can also be acute (short-term) or chronic (long-term) in nature. Acute stress may occur after hearing a sudden, loud noise, whereas chronic stress may stem from ongoing financial problems. Chronic stress is associated with a number of conditions, including insomnia, major depression and digestive problems.

Reactions to a specific stressor (an agent that causes stress) vary among individuals. However, stress affects everybody in predictable, physical ways. It causes the release of certain chemicals that raise the blood pressure and heart rate, increase the metabolic rate, and prepare the body for a “fight or flight” response.

Stress can be caused by a number of factors including life events, such as being laid off from work, and daily events, such as traffic congestion. Genetic predisposition may also play a role in how a person copes with stress.  

Symptoms of stress can be either behavioral or physical. Behavioral symptoms of stress include either difficulty sleeping (insomnia) or excessive sleeping (hypersomnia), nightmares and irritability. Physical symptoms of stress include anxiety, depression and headaches.