Male Holocaust survivors have a longer life expectancy compared to those who didn't experience the Holocaust, according to a recent study conducted at the University of Haifa jointly with Leiden University.

The results have just been published in PLOS ONE.

This is the first study to examine data on the entire Jewish Polish population that immigrated to Israel before and after World War II, using the population-wide official database of the National Insurance Institute of Israel. "Holocaust survivors not only suffered grave psychosocial trauma but also famine, malnutrition, and lack of hygienic and medical facilities, leading us to believe these damaged their later health and reduced life expectancy. Surprisingly, our findings teach us of the strength and resilience of the human spirit," said the leading professor of this research, Prof. Avi Sagi-Schwartz, from the Dept. of Psychology and the Head of the Center for the Study of Child Development at Haifa University.

Previous studies showed a traumatic experience may shorten life-expectancy and even found genetic proof that trauma may lead to a shortening of the chromosome ends in the human DNA, responsible for the lifespan of human body cells. These facts led the researchers to examine whether Holocaust survivors really do have a shorter lifespan.

This research, conducted in collaboration with Prof. Shai Linn, Dean of the Faculty of Social Welfare and Health Sciences at Haifa University, Prof. Marian J. Bakermans-Kranenburg and Prof. Marinus H. van IJzendoorn from Leiden University in The Netherlands, was the first to be based on population-wide data derived from the official database of the National Insurance Institute of Israel, examining the entire Jewish Polish population that immigrated to Israel before and after World War II.

The researchers compared between a population of Holocaust survivors who were 4-20 years old in 1939 and who immigrated to Israel between 1945-1950 and a population of Polish immigrants, of the same age group, who immigrated before the break of World War II in 1939. In total, data on more than 55,220 men and women immigrants from Poland was examined.

The findings showed life-expectancy in the survivors' population was 6.5 months longer than that of the immigrant population that did not experience the Holocaust. But when the researchers examined the differences between men and women they found that within the entire female population of Polish immigrants, there was no significant difference in life-expectancy between female survivors and women who didn't experience the Holocaust. The differences in the male populations however were significant, with male Holocaust survivors living on average 14 months longer. In addition, the older the surviving men were at the time of the Holocaust, the bigger the difference in life-expectancy was between them and their peers without Holocaust experience. "Men who were 10-15 years old during the war and in their early adolescence had a 10 month longer life-expectancy compared to the comparison group. Men who lived through the Holocaust when they were 16-20, had an even bigger difference in life-expectancy, 18 months longer than their peers with no Holocaust experience," said Prof. Sagi-Schwartz.

According to the researchers, one possible explanation for these findings might be the "Posttraumatic Growth" phenomenon, according to which the traumatic, life-threatening experiences Holocaust survivors had to face, which engendered high levels of psychological distress, could have also served as potential stimuli for developing personal and inter-personal skills, gaining new insights and a deeper meaning to life. All of these could have eventually contributed to the survivors' longevity. "The results of this research give us hope and teach us quite a bit about the resilience of the human spirit when faced with brutal and traumatic events," concluded Prof. Sagi-Schwartz.