Studies suggest that the inability to adapt to stress is associated with the onset of depression or anxiety.

Some evidence suggests that the repeated release of stress hormones produces hyperactivity in the hypothalamic-pituitary-adrenal (HPA) system, and disrupts normal levels of serotonin, the brain chemical that is critical for feelings of well-being. Some people appear to be more at risk for an overactive HPA system under psychological disorders, including those with personality traits that cause perfectionism. On a more obvious level, stress reduces quality of life by affecting feelings of pleasure and accomplishment. In addition, relationships are often threatened in times of stress.

Oxidative stress reflects an imbalance between the systemic manifestation of reactive oxygen species and a biological system's ability to readily detoxify the reactive intermediates or to repair the resulting damage. Disturbances in the normal redox state of cells can cause toxic effects through the production of peroxides and free radicals that damage all components of the cell, including proteins, lipids, and DNA.

Healthcare costs are much higher in workers who are stressed or depressed than in others who are not stressed. Nearly half of American workers describe their jobs as very stressful, making job-related stress an important and preventable health hazard. In a struggling economy, worry about job loss produces a tremendous amount of stress.

Several studies are now suggesting that job-related stress is as great a threat to health as smoking or not exercising. Stress impairs concentration, causes sleeplessness, and increases the risk for illness, back problems, accidents, and lost time from work. Work stress can lead to harassment or even violence on the job. At its most extreme, chronic stress places a burden on the heart and circulation that in some cases may be fatal.

Stress affects most people in some way. Acute stress disorders leads to rapid changes throughout the body. Almost all body systems (the heart and blood vessels, immune system, lungs, digestive system, sensory organs, and brain) gear up to meet perceived danger.

These stress responses could prove beneficial in a critical, life-or-death situation. Over time, however, repeated stressful situations put a strain on the body that may contribute to physical and psychological problems. Chronic (long-term) stress can have real health consequences and should be addressed like any other health concern.

Post-traumatic stress disorder (PTSD) is a reaction to a very traumatic event, and it is typically classified as an anxiety disorder. The event that brings on PTSD is usually outside the norm of human experience, such as intense combat or sexual assault. The patient struggles to forget the trauma and frequently develops emotional numbness and event-related amnesia. Often, however, there is a mental flashback, and the patient re-experiences the painful circumstance in the form of dreams and disturbing thoughts and memories. These thoughts and dreams resemble or recall the trauma. Other symptoms may include a lack of pleasure in previously enjoyed activities, hopelessness, irritability, mood swings, sleep problems, inability to concentrate, and an excessive startle-response to noise.

Fortunately, research is showing that lifestyle changes and stress-reduction techniques can help people manage stress.

People who are under chronic stress often turn to tobacco, alcohol and drugs for relief. Stress compounds the damage these self-destructive habits cause under ordinary circumstances. Many people also resort to unhealthy eating habits, smoking, or passive activities, such as watching television when they are stressed.

Alcohol affects receptors in the brain that reduce stress. Lack of nicotine increases stress in smokers, which creates a cycle of dependency on smoking.

The cycle is self-perpetuating: a sedentary routine, an unhealthy diet, alcohol abuse, and smoking all promote heart disease. They also interfere with sleep patterns, and lead to increased rather than reduced tension levels. Drinking four or five cups of coffee, for example, can cause changes in blood pressure and stress hormone levels similar to those produced by chronic stress. Animal fats, simple sugars, and salt are known contributors to health problems.

Stress can be a factor in a variety of physical and emotional disability, which should be professionally treated. Many stress symptoms are mild and can be managed with over-the-counter medications (for example, aspirin, acetaminophen, or ibuprofen for tension headaches; antacids, anti-diarrhea medications, or laxatives for mild stomach distress). A physician should be consulted, however, for physical symptoms that are out of the ordinary, particularly those that get worse or wake a person up at night. A mental health professional should be consulted for unmanageable acute stress or for severe anxiety and depression. Often short-term therapy can resolve stress-related emotional problems.

The Depression Anxiety Stress Scales (DASS) and other assessment tools are available to help identify aspects of stress such as difficulty relaxing, nervous arousal and being agitated/irritable, and determine whether depression and/or anxiety are present as well. The DASS is available to the public online.

During stress, breathing becomes shallow and rapid. Taking a deep breath is an automatic and effective technique for winding down. Deep breathing exercises consciously intensify this natural physiologic reaction and can be very useful during a stressful situation, or for maintaining a relaxed state during the day.

Meditation, used for many years in Eastern cultures, is now widely accepted in this country as a relaxation technique. The goal of all meditative procedures, both religious and therapeutic, is to quiet the mind (essentially, to relax thought). Small studies have suggested that regular meditation can benefit the heart and help reduce blood pressure. Better research is needed, however, to confirm such claims.

Statistics: Global

In USA, 75% of adults continue to report moderate to high levels of stress. 10-15% of population remains depressed at any given time of the year. 80% of workers feel stress on job. Nearly 60% Chinese employees feel stress at workplace with the highest rise of 86%. Alarmingly 91% of Australians feel stress in at least one important aspect of their lives that costs approximately $14.2 billion to Australian economy. In 2007/08, an estimated 442,000 individuals in Britain experienced work-related stress that cost £28.3 billion per year.

According to the Fourth European Working Conditions Survey, stress was experienced by approximately 22% of workers from European Union. The highest level of stress was reported in Greece (55%), and then in Slovenia, Sweden (38%), and Latvia (37%). Lowest stress levels were noted in the United Kingdom (12%), Germany, Ireland, and Netherlands (16%). In Czech Republic (17%), and in France and Bulgaria (18%).

Mental Health Projects receive funding from various foundations across the globe. Baxter International Foundation, Hogg foundation- USA, Bristol-Myers Squibb Foundation- USA, Irish Hospice Foundation- Belgium, De Overmolen- Ireland, Samusocial- Belgium are few of them.

Major antidepressant producing industries i.e. Eli Lilly, AstraZeneca, Johnson & Johnson, Bristol-Meyers Squibb, GlaxoSmithKline and Pfizer etc. are investing and generating good revenues.

Statistics: Spain

Stress is most prevalent in the education and health sectors, as well as in agriculture, hunting, forestry & fishing. 42.9% workers from financial intermediation sector, 29% clerks and 24% technicians consulted a doctor most often about stress-related health issues. Symptoms diagnosed were difficulty in getting to sleep or sleeping badly, headaches, dizziness, and so forth.  MEDLINE, Spanish journals, reference lists, national databases, and European and Spanish official documents describe the current state of the MHCS that reveals the existence of great variability among the autonomous communities with respect to mental health resources and provision of care.

Currently, various Associations and Foundations are funding Mental Health Projects in Spain. Associacion Espanola de Neuropsiquiatria (AEN), FEAFES, Fundacion Intras, Fundacion Mundo Bipolar, Associacion Nacional de Enfermeria en Salud Mental Andalusian School of Public Health (EASP), ANAR Foundation etc. Also many Universities are providing a valuable support in the field of stress management. University of the Basque Country, University of Barcelona, University of Valencia are few of them.