Is it the long hours, lack of exercise, break room donuts, or just the sheer stress of that 9 to 9 job that could be hurting workers’ heart health? Researchers aren’t sure yet, but cite all these factors—lifestyle and biological—as culprits in crimes of the heart.

The London study is said to demonstrate the strongest link yet between work stress and worsening heart health. The research, which examined the health of more than 10,000 British civil servants over a 12 year time period, demonstrates possible biological changes in the body which are provoked by work stress, said Tarani Chandola, an epidemiologist at University College London, publicly.

"This is the first large-scale population study looking at the effects of stress measured from everyday working life on heart disease," said study leader Chandola, in a public statement. "One of the problems is people have been skeptical whether work stress really affects a person biologically."

Chronically stressed out workers are 68 percent more likely to develop heart disease, with those over age 50 the most profoundly affected by at-work woes. According to the report, published in the European Heart Journal, “This study adds to the evidence that the work stress-coronary heart disease association is causal in nature."

Chandola said publicly that high stress lifestyle habits, like lack of exercise, poor diet, smoking, and excessive drinking, all promote heart disease, but adds that chronic stress also creates biological changes in the body that do the same. Workers under too much pressure demonstrated high blood levels of cortisol, a stress hormone, which can cause heart and blood vessel damage, said Chandola.

“If you are constantly stressed out these biological stress systems become abnormal," Chandola said in a public statement.

Social psychologist Susan Newman, PhD, tells demo dirt that these study results can translate overseas as well. “Americans are chronically overscheduled, overworked and overwhelmed,” Newman says. “The general thinking is it’s because we have too much to do. The real reason we’re stressed and exhausted (and put our health at risk) is because we can’t say no.”

“The inability to say ‘no’ to our bosses and colleagues, our friends and family can wreak havoc with our health. People-pleasers work extra long hours and take on too many projects that raise anxiety levels,” Newman, the author of The Book of NO: 250 Ways to Say It—and Mean It and Stop People-Pleasing Forever contends.

“Any type of stress, but especially the low-grade, chronic stress that we experience at work leads to both behavioral changes (less exercise, eating more ‘comfort foods,’ drinking, smoking, etc) and biochemical changes (higher levels of stress hormones like cortisol, which can suppress the immune system, increase blood pressure and cholesterol, elevate appetite, reduce sex drive, lead to memory and emotional problems, etc),” nutritional biochemist Shawn M. Talbott, Ph.D, says.

Talbott, the Utah-based author of The Cortisol Connection Diet—The Breakthrough Program to Control Stress and Lose Weight suggests five ways to combat the consequences of stress on health, which he emailed to demo dirt:

1. Have an outlet (a hobby or some diversion outside of work)

2. Do whatever you can to make the sources of your stress more   "predictable" or learn to develop more "control" over those stressors—this means to identify patterns related to when your stressors might appear

3. Hang out with friends (avoid social isolation)—tough times are always easier when you're around other people

4. Learn to tell the difference between "big" issues and "little “issues

5. Look on the bright side (really)—as simplistic as it sounds, the fact that you can look to "what is improving" in a given situation can help to psychologically buffer the stress in others areas.