How has the war in Gaza affected overall mortality among Gazans? According to a paper published in the Lancet in February, life expectancy in Gaza fell by 35 years during the first 12 months of the war. This is a remarkable figure. For comparison, life expectancy fell by “only” 21 years during the war and genocide in Bosnia during the 1990s. But can the figure be trusted?
The first thing to note is that the lead author, Michel Guillot, is a respected demographer at the University of Pennsylvania who has published numerous papers on mortality analysis. He is not some political activist. What’s more, he and his colleagues made their data and code publicly available for anyone to check. So far as I’m aware, no errors have been uncovered since the paper was published.
To estimate life expectancy in Gaza during the first 12 months of the war, Guillot and colleagues relied on the list of killed individuals published by the Gaza Health Ministry, which provides the ages and sexes of the deceased. Specifically, they computed age-specific death rates by combining this data with the age and sex distribution for the whole population, and then converted these into life expectancies using standard methods. The authors found that life expectancy fell by 38 years for males and 30 years for females.
However, the Gaza Health Ministry’s list of killed individuals has come under sustained criticism, with critics alleging that the number of deaths is inflated — particularly the number of deaths of women and children. For example, a report published by the Henry Jackson Society identified “distortion of statistics, misreporting of natural deaths, deaths from before the war started and a high likelihood of combatant deaths being included”. Yet this report has itself been subject to critique, with two critics noting that “the small number of errors identified is insufficient to meaningfully shift overall casualty demographics”.
To address the possibility that the Gaza Health Ministry’s figures are inflated, Guillot and colleagues cross-checked the names against the UNRWA’s register of refugees living in Gaza. This is a register of people “whose normal place of residence was Palestine during the period June 1, 1946, to May 15, 1948, and who lost both home and means of livelihood as a result of the 1948 Arab-Israeli war”, as well as their descendants. It serves as the basis for the provision of services to Palestinian refugees, who comprise 66 per cent of Gaza’s population.
Out of 34,344 individuals included on the Gaza Health Ministry’s list as of September 2024, the authors found that 64 per cent also appeared on the UNRWA’s refugee register — which is almost identical to the percentage of the population comprising refugees. This provides strong evidence that the Gaza Health Ministry’s figures are not substantially inflated, and is consistent with previous studies that have validated the figures in other ways.
Could the Gaza Health Ministry’s list include a large number of individuals who have real identities but are not actually deceased? Guillot and colleagues find this implausible. Once someone is declared dead by the Gaza Health Ministry, they are no longer entitled to services from the UNRWA, meaning that any living person included on the list would have an incentive to remove their name. As of February, the UNRWA was aware of only two such cases.
A 30-year drop in life expectancy is extraordinary. Can it really be true?
Another reason to trust the Gaza Health Ministry’s figures is that there are reports, based on off-the-record conversations with Israeli intelligence personnel, that Israeli intelligence relies on them “almost exclusively”. They also proved accurate in previous conflicts.
A 30-year drop in life expectancy is extraordinary. Can it really be true? You have to remember that Gaza is extremely young: almost half the population is under the age of 18. As young people usually have very low mortality rates, there were only 6,454 deaths in Gaza in the year before the war. An additional 41,615 deaths — what the authors assume in their central variant — therefore represents a huge increase of around 630 per cent. Furthermore, when large numbers of young people die, this has a disproportionate impact on life expectancy because they lose many potential years of life.
By way of comparison, the first year of the Covid pandemic saw the number of deaths in Britain rise by about 19 per cent, and excess deaths were of course heavily concentrated in older age groups (there were none in the 0–14 age group). In Gaza, almost a third of those who’ve died were younger than 18.
As a matter of fact, Guillot and colleagues suggest that their estimates are conservative because they ignore indirect deaths from the war (e.g., people who died due to lack of medicine or healthcare). “When information on indirect deaths becomes available,” the authors write, “we will likely find even greater losses.”
On the other hand, it has been claimed since the study was published that 3,400 deaths were “quietly dropped” from the Gaza Health Ministry’s list and that these deaths “never happened”. However, others maintain that the vast majority were removed for innocent reasons (e.g., they were indirect deaths). Whatever the truth, 3,400 deaths would represent only 8 per cent of the total in the authors’ central variant and could not substantially affect their results.
While Guillot and colleagues’ findings still need to be scrutinised and replicated by other scholars, they imply a level of mortality in Gaza that is almost unprecedented in modern times. Indeed, the fall in life expectancy reported in the Lancet is greater than that seen during the Rwandan genocide of 1994.
