New research is showing those who get annual flu shots could be at less risk for a recurring heart problem.

Researchers at the University of Toronto reviewed four flu vaccine studies that kept tabs on heart attacks and other cardiovascular issues.

They found patients who had suffered a recent heart attack, had a 55 percent lower risk of having another heart issue if they have had their flu shots.

Doctors who reviewed the study believe the results prove influenza is a body-wide infection that can worsen underlying conditions.