According to a Heart Foundation study of the physical changes suffered immediately after a profound loss, grieving people were at significantly higher risk of heart problems, said lead researcher Thomas Buckley.
"We found higher blood pressure, increased heart rate and changes to immune system and clotting that would increase the risk of heart attack," Buckley said.
Of the 160 people studied, half were mourning the loss of a partner or child, and their risk of heart attack increased six-fold, he said.
The risk, which was evident in people as young as 30, reduced after six months and levelled out after two years, he added.
A sudden flood of stress hormones is believed to be behind the grief-induced heartache, a condition that earlier studies have found is more likely to affect women.