The pain of losing a family member speeds up ageing.
Data from nearly 4,000 people in the United States who had been followed since they were teenagers in the mid-1990s showed that people who had experienced two or more bereavements had older biological ages than those who had not.
It was also found that the impact of a family member's death was more severe during childhood and early adulthood.
Dr. Allison Aiello, lead author of the study at Columbia University, said: "Our study shows strong links between losing loved ones across the life course from childhood to adulthood and faster biological ageing in the US."
The experts have been able to show the connection between grief and ageing but are uncertain about what causes the trauma of losing a loved one to harm a person's own health.
Dr. Aiello added: "The connection between losing loved ones and health problems throughout life is well-established.
"But some stages of life might be more vulnerable to the health risks associated with loss and the accumulation of loss appears to be a significant factor."