Updated

Work, money and the economy are the biggest cause of Americans' stress, according to research recently released by the American Psychological Association (APA). And, the majority of Americans don't seem to realize how big an impact it's having on their overall physical and psychological health.

The good news is that the percentage of Americans who report feeling extreme stress dropped, from 32 percent to 22 percent since 2007, when the APA conducted its first Stress in America survey. On a scale of 1 to 10, the mean rating for stress in 2011 fell to 5.2, the lowest level in five years (it was 5.4 in 2009 and 2010; 5.9 in 2008; and 6.2 in 2007). Extreme stress was likely highest in 2007 because that was the start of the economic downturn, the researchers suggest.

The bad news from APA's latest data is noteworthy: A significant number of respondents reported that stress has only a slight or no impact on their physical health (31 percent) or on their mental health (36 percent). That's true even though stress is a proven precursor of many chronic conditions, such as depression and cardiovascular disease, and often makes existing illnesses worse, said APA CEO Norman B. Anderson.

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"Seventy-five percent of health-care costs are associated with chronic illnesses," said Anderson. "What's a key driver of chronic illnesses? Stress."

Anderson said that most Americans don't see a connection between stress and their overall health.

It's a vicious cycle since those with the highest stress are often those with chronic conditions, said APA President Suzanne Bennett Johnson.

Most common stress causes

According to the APA's research, money and work are the two most common causes of stress among Americans. Seventy-five percent of Americans said money was their biggest cause of stress, while 70 percent said work causes most of their stress. The economy, relationships, family responsibilities and health respectively were cited as causes of most people's stress. Being a caregiver is also a significant source of stress for many Americans.

The survey also found that caregivers and younger Americans are experiencing higher levels of stress, while East Coast dwellers reported they have a slightly more difficult time managing their stress levels.