Mexico’s drug war violence became so acute during the government’s militarised crackdown on organised crime that it caused male life expectancy rates to drop by an average of several months, reversing a decade’s worth of public health improvements, a new study has shown.

As violence worsened between 2005 and 2010, life expectancy rates fell in all of Mexico’s 31 states, including regions perceived to have escaped the conflict, according to the study published on Tuesday in the journal Health Affairs.

Life expectancy fell by as much as three years in Chihuahua state, which includes Ciudad Juárez – once considered the murder capital of the world. But states not nearly as affected by violence such as Oaxaca and Tlaxcala also saw declines of six months.

The drop in life expectancy coincides with a period of escalating violence between rival cartels, and then president Felipe Calderón’s 2006 decision to deploy federal forces against the traffickers.

“After 2005, that’s when life expectancy goes down in all the states. That is what made me think that it is homicide that is having a big impact,” says Hiram Beltrán-Sánchez, the lead researcher on the study.



Two authors of the study told the Guardian that the decline in life expectancy was directly related to the rise in the homicide rate after the drug war began and not merely a coincidence.

“Homicides were going down” from 2000 to 2005, Beltrán-Sánchez, a professor of community health studies at the University of California Los Angeles, said. “After 2005, when the whole thing exploded and military operations began moving through the country, that’s when the homicides went up, very much across the board.”

Mexico had made gains in life expectancy over the previous six decades as public health and living standards improved and more Mexicans gained access to health services. Beltrán-Sánchez said he was expecting to see an increase of “three or four years” during the last decade, but found a decrease in life expectancy of 0.6 years for men and almost no change for women.



The reversal came as the federal government extended a universal healthcare coverage to millions of impoverished Mexicans through a program known as Seguro Popular – a measure that researchers say should have increased life expectancies.



Mortality from diabetes – problematic in a country which consumes staggering amounts of soda – actually levelled off between 2005 and 2010 and would have contributed to gains in life expectancy without such high homicide rates

“The implementation has been slow, but the little progress that they did make [with Seguro Popular] was wiped out by the increase in homicides,” he said.



Life expectancy for a Mexican male is now slightly less than 72 years, six months lower than in 2005.



“This has become an issue of national relevance, of public health relevance, rather than some isolated events,” Beltrán-Sánchez said. “If [government officials] continue to see these as isolated events, they won’t be able to stop it.”



Mexico’s drug war has claimed more than 100,000 lives and sent the homicide rate from nine murders per 100,000 persons in 2005 to 22 murders per 100,000 in 2010.



The country’s homicide rate is still lower than in other Latin American countries, especially those in Central America



Figures released earlier this week showed that the murder rate in El Salvador rose to 104 per 100,000 habitants in 2015 – the bloodiest year since the end of the country’s civil war in 1992.