While these survivors suffer more serious illnesses than their peers, they also die at later ages, according to a surprising new study.

"The overall mortality rate was lower among Holocaust survivors compared with the control group," researchers report. (Photo: Rawpixel/Unsplash)

Why do some people live longer than others? Genetics play a major role, as do health-related habits, plus long-term physical and emotional stress. It might be natural to assume that enduring a prolonged threat of imminent annihilation would exact a long-term toll that could lead to premature death.

In fact, new research from Israel finds the opposite is true.

A new study reports that a population of Holocaust survivors were more likely to suffer from a number of serious illnesses than a group of matched peers who had avoided the tragedy. But the survivors also tended to die at an older age than their counterparts who hadn't been subjected to that unthinkable trauma.

These findings may reflect "improved health literacy and unique resilience characteristics among Holocaust survivors," writes a research team led by Dr. Gideon Koren of the Morris Kahn and Maccabi Health Data Science Institute in Tel Aviv. The team's study is published in the journal JAMA Network Open.

The study compared medical histories and death rates between two groups of Israelis: 38,597 who were born in Europe between 1911 and 1945, and 34,931 men and women who were born in Israel during those same years. Those in the first group were identified as "Holocaust survivors"; the researchers used a fairly loose definition of that term, comprising individuals who were forced to live in ghettos or exile, as well as in camps.

Examining the participants' health data from 1998 through 2017, the researchers found a clear, if counterintuitive, pattern.

"The Holocaust survivors had higher rates of reported hypertension, obesity, chronic kidney disease, cancer, dementia, ischemic heart disease," and heart attacks, they report. The women also suffered more osteoporotic fractures.

Yet "the overall mortality rate was lower among Holocaust survivors compared with the control group," the researchers report. "After adjustment for sex, socioeconomic status, and body-mass index, mean age at death was significantly higher in the survivor group compared with the control group."

The researchers note there is "ample evidence" that the serious diseases experienced by so many survivors tend to lower life expectancy. So what's going on with this group?

"It is conceivable that the stress response among Holocaust survivors is different," the researchers speculate. After all, these subjects have demonstrated a "Darwinist ability to survive"; perhaps vigor that is reflected in the group's enhanced ability to fight off the effects of even very serious diseases.

In addition, the researchers point to a recent study that found Holocaust survivors living in Israel were far more likely than their peers to list "maintaining good health" as an important life-coping strategy. This finding suggests that, for whatever reason, survivors are more likely to get medical screenings, which leads to earlier diagnoses and better outcomes.

Those are plausible theories, which deserve further study. But it's also possible the answer is more simple. Perhaps the terrifying experience of waking up each morning knowing you could die that day instills an intense, long-lasting will to live.