Dull, steady, unexciting jobs may make the heart beat in an unchanging, rapid rhythm -- which in turn could lead to heart disease, British researchers reported.

They found that men with "low-grade jobs," meaning they had little control over daily tasks, and men in low social positions had faster and less-variable heart rates.

"This finding helps explain why men with low-paying jobs and less education have a higher risk for heart disease, a trend that has been evident for the last 30 years," said Dr. Harry Hemingway, of University College London Medical School, who led the study.

"The heart doesn't, or shouldn't, beat like a metronome," Hemingway said in a statement.

A healthy heart rate varies, he said.

His team studied 2,197 men aged 45 to 68 who worked for the British government, and talked to them about friends and family, education and lifestyle.

Job control was rated on a 15-item scale.

Steadier, faster heart rates were consistently seen in the men with lower social positions, less job control and higher depression.

Writing in the journal Circulation, Hemingway and colleagues said they found that heart rates of men in low-level positions were an average 3.2 beats per minute faster than men in top-level positions.

"Arteries behave as if they know how much a person makes and how much education they have had," Hemingway said.

The effect was clear even after taking into account factors such as smoking, poor diet and lack of exercise -- all of which also can adversely affect heart rate, Hemingway said.

It may be possible to help prevent heart disease by changing workplace conditions, Hemingway said.

"We hope this information provides insight into the mechanisms at work so that there is a possibility for interventions that will change this outcome," he said.