Try not to get worked up on the job: New research suggests that work-related stress can be as harmful as smoking.

In a study published in the British Medical Journal, Harvard University researcher Yawen Chang, Ph.D., surveyed more than 21,000 women and found that those with the most demanding jobs, little control over their work environment, and lack of support from co-workers and supervisors were more likely to suffer from stress than those more content with their jobs. They also found that women suffered physical effects: Symptoms ranged from anxiety to difficulty performing daily tasks like climbing stairs.

But in a new twist on an old issue, researchers don't suggest behavioral changes for alleviating on-the-job stress. Instead, they recommend that employees alter their work conditions-by reducing workload, increasing control over their work environment and seeking more social support.

In a related study, Tesfaye Belay, Ph.D., a microbiology researcher at Atlanta's Morehouse School of Medicine, confirmed that stress can make you physically sick. In lab studies, Belay mixed bacteria with the stress hormones epinephrine and nor-epinephrine and found that increasing the hormones' quantities caused the growth of certain bacteria-some of which can lead to health problems like pneumonia. In light of his findings, presented at an American Society for Microbiology meeting, Belay said that if [people] take measures to help themselves relax, the risk of contracting an infection will probably be reduced.