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Nearly half of all workers suffer from moderate to severe stress while on the job, according to a survey. And 66% of employees report that they have difficulty focusing on tasks at work because of stress. Stress has been called the "health epidemic of the 21st century" by the World Health Organization and is estimated to cost American businesses up to $300 billion a year.

But there are ways to reduce its impact on human lives and companies' bottom line, even though stress is a daunting, pervasive problem, experts say. A recent survey of 2,500 employees by ComPsych, a provider of employee assistance programs (EAPs), underscores the dimensions of the problem.

In addition to reporting difficulties with focusing on tasks at work, employees also said that stress was responsible for errors and/or missed deadlines (21%), trouble getting along with co-workers/superiors (15.5%), missed days (14.9%) and lateness (14.4%). [See related article: The Top 10 Most and Least Stressful Jobs]

Due in part to the prevalence of stress in today's workplace, behavioral disability costs have increased more than 300% in the past decade and account for 30% of all disability claims. In addition, medical doctors suggest that stress is the causative factor of illness underlying more than 70% of all visits to the family doctor.

High levels of unemployment and job uncertainty remain; organizations are focused on driving productivity with a smaller workforce, and structural changes in the overall economy continue to affect workers across the globe.

But employers do have tools they can leverage to address workplace stress, experts say. Employee assistance programs that include work-life services are proven to help reduce employee stress, decrease absenteeism and turnover, and improve productivity. In addition, research has shown that EAPs have been shown to directly impact disability claims.

"Unchecked stress can result in a number of productivity-sapping outcomes, from diminished work quality to absenteeism to co-worker clashes," said Dr. Richard A. Chaifetz, chairman and CEO of ComPsych.

"Organizations looking to compete in a volatile marketplace are proactively addressing stress — this can enhance employee well-being and therefore engagement. Leveraging the employee assistance program is an important step in dealing with workplace stress. A comprehensive EAP not only provides individual counseling, but organizational consulting on change management, team building and interpersonal skill development."

The American Psychological Association recommends that workers should track their stressors for at least a week. In a journal, write down situations where you felt your stress level increase. Record the circumstances of the incident. Where were you? Who were you with? How did you respond to the situation? Did you raise your voice? Did you retreat from the situation? Knowing what got you stressed as well as your reactions will assist in deciding how to best handle these situations in the future.

Develop a support system to alleviate stress at work. Connect with colleagues as a way to help keep stress levels under control. When you’re feeling overwhelmed, find a trusted member within your workplace to talk things through. Remember to remain supportive in turn when a coworker is feeling stressed and needs help. If you feel as though there is no one you can lean on at work, focus on building new friendships with coworkers. You could also have a strong support system outside of the office. Talk to friends and family members about what is bothering you at work. Outside influences can sometimes give you much-needed perspective on the situation.

Remember to stay healthy to improve stress levels. Your food choices and exercise habits have a large impact on how you feel throughout the day. A common problem is that stressed individuals turn to "comfort" food such as sweets and fried dishes to alleviate stress. These foods actually cause blood sugar levels to crash and your mood is likely to worsen. Instead, eat a well-rounded diet made up of mostly lean proteins, vegetables, fruits and healthy fats. Avoid caffeine, nicotine, and alcohol since these substances are detrimental to your mental health. Aim for at least 30 minutes of exercise each day to boost your mood.

Time and task management is vital to keeping work stress at bay. If you're overtaxing yourself, burnout is bound to happen. Aim to always keep a healthy work and family life balance. When feeling tired or overwhelmed at work, take a break and go for a short walk. Eat lunch away from your desk each day to give yourself a mental vacation. Remember to prioritize the most important work tasks and delegate responsibilities when it’s plausible.