Raleigh, N.C. — Doctors know that healthy diet and exercise can help prevent a second heart attack. Even if people cut back on calories, though, a lot of them don't cut back on stress – and that is bad, according to new research.

Researchers looked at how a stressful job may affect the risk of another heart attack.

Michel Heroux, a Canadian patient, had a heart attack in 1996, then went back to his very stressful executive job.

“In that kind of a job, you cannot make many mistakes,” Heroux said in describing the ongoing pressure.

In 2005, Heroux had another heart attack, and he said his doctor warned him “stress is killing you. You don't have any more of the arteries in the heart to go on in a very stressful environment.”

The situation is not unusual, a study in the Journal of the American Medical Association shows.

“Those who returned to work in a stressful job had two times the risk of a new heart attack compared [with] those who returned to low-stress jobs,” said Chantal Brisson, Ph.D., who works at Laval University in Quebec.

Researchers studied almost a thousand heart attack patients to see who had second heart attacks and who had stressful jobs.

That risk appeared to increase regardless of the severity of the first heart attack, what medications the patients were on, other medical conditions, whether they smoked or their family history.

“A stressful work situation is when a person has to do a large amount of work in a short amount of time,” Brisson said, along with limited ability to make decisions and be creative.

That may describe many jobs, but heart attack patients may need special consideration to reduce work stress.

Heroux cut his work stress. He found a different job at the same place and same pay.

“I work only 2 1/2 days a week because I am a semi-retired person, so the level of stress has been lowered very considerably,” Heroux said. He said he'd like to think others could have the same choices, especially if they're at risk of a second heart attack.