War reshapes nearly every dimension of human life, from brain chemistry to community trust to childhood development. Roughly one in four civilians living in conflict zones develops symptoms of PTSD or depression, but the damage extends far beyond mental health. War destroys healthcare systems, contaminates environments, displaces millions, and leaves biological marks that can pass from parent to child. Here’s what the evidence shows about how armed conflict changes people.
Mental Health After Conflict
A large meta-analysis of civilians in armed conflict zones found that about 24% showed symptoms of PTSD and 26% showed signs of depression. Anxiety disorders affected roughly 14% of people exposed to conflict. Those numbers represent averages; depending on the intensity and duration of violence, PTSD rates in some populations climb as high as 66%.
These aren’t short-lived reactions. Survivors of sexual violence in northern Uganda reported being plagued by anxiety, depression, nightmares, and suicidal thoughts 10 to 15 years after their experiences ended. The psychological toll compounds over time, particularly when people lack access to treatment, which is the norm in most conflict-affected areas.
More People Die From Hunger and Disease Than Bombs
The most lethal aspect of war isn’t direct violence. In Africa over a 20-year period, five million children under age five died from the indirect consequences of warfare: hunger, infectious disease, and collapsed medical systems. That number was three times the total number of combatants killed in fighting across the entire continent during the same period.
When war destroys hospitals, supply chains, and sanitation systems, preventable conditions become fatal. Vaccination coverage drops sharply. Across 85% of studies examining the link between conflict and immunization, war was associated with reduced vaccination rates, sometimes by more than 20 percentage points. In Cameroon, coverage for a key childhood vaccine series dropped from 90% to 55% in a single year of conflict. In Yemen, measles vaccination fell from 75% to 66%, and tuberculosis vaccination plunged from 73% to 49%. Children in areas affected by Boko Haram in Nigeria were 35% less likely to have ever been vaccinated at all. These gaps don’t just affect individual children. They create the conditions for outbreaks of diseases that had been nearly eradicated.
How Children’s Development Changes
War strikes hardest during the period when the brain is growing fastest. Infants and young children exposed to conflict show impairments in motor skills, cognitive development, and the ability to regulate emotions. Chronic stress during early life physically alters brain development, leading to difficulties with attention, learning, and emotional control that can persist well beyond childhood.
The damage also works through relationships. War disrupts the stable, predictable caregiving that infants need to build secure attachments. Separation from parents, witnessing violence, and living in a constant state of alertness can produce attachment disorders and lasting difficulty forming healthy relationships. Children of war-traumatized parents face higher rates of emotional and behavioral problems even when those children weren’t directly exposed to violence themselves.
Trauma That Passes Between Generations
The children and grandchildren of war survivors can carry biological traces of their parents’ trauma. Research on Holocaust survivors and their offspring revealed something striking: both generations showed changes to the same gene involved in regulating the body’s stress response. Offspring of Holocaust survivors were more likely to have lower baseline cortisol levels and a more reactive stress system, patterns typically associated with PTSD, even without having experienced trauma themselves.
These findings point to epigenetic transmission, where extreme stress chemically modifies how genes are expressed, and those modifications can be passed to the next generation. The science is still developing, but it helps explain a pattern clinicians have observed for decades: the children of trauma survivors often struggle with anxiety and stress regulation in ways that seem disproportionate to their own life experiences.
Displacement on a Global Scale
By the end of 2024, 123.2 million people worldwide were forcibly displaced, the vast majority driven from their homes by conflict, persecution, and violations of international humanitarian law. That’s roughly the population of Japan, uprooted. By April 2025, the number had dipped slightly to about 122 million, the first decrease in over a decade, though still staggering.
Displacement compounds every other effect of war. Refugees lose access to healthcare, education, stable housing, and social networks all at once. Children miss years of schooling. Families are separated. People who were middle-class professionals find themselves dependent on aid in overcrowded camps, often for years or decades.
Sexual Violence and Its Lasting Toll
Women and girls in conflict zones face systematic sexual violence that produces health consequences lasting decades. A study of female survivors in northern Uganda found that over two-thirds reported persistent physical problems tied to their experiences, including chronic pain, untreated sexually transmitted infections, recurring vaginal infections, and incontinence from injuries sustained during repeated rapes. Nearly all participants described ongoing psychological suffering, most commonly anxiety, depression, nightmares, and thoughts of self-harm.
These survivors were interviewed 10 to 15 years after returning from captivity. Most of their physical conditions remained untreated. The combination of physical disability, psychological distress, and social stigma creates a cycle that is extraordinarily difficult to break, particularly in post-conflict settings where healthcare resources are scarce and the topic remains taboo.
Toxic Environments Long After Fighting Stops
Armed conflict releases toxic chemicals into soil, water, and air. A review of 66 studies found that civilians are exposed to a range of harmful substances during and after war, from smoke and dust to heavy metals from munitions. While dramatic chemical attacks get the most attention, the vast majority of civilians are actually harmed by the more mundane, ubiquitous contaminants present in every conflict: particulate matter from explosions, industrial pollutants released when infrastructure is bombed, and metals that leach into groundwater from spent ammunition.
These exposures persist long after the fighting ends, affecting farming communities and children playing in contaminated areas years or decades later. Despite this, research on civilian toxic exposures in war zones remains scarce, and most affected populations live in the Global South with limited access to monitoring or treatment.
Erosion of Trust and Social Bonds
War doesn’t just damage individuals. It rewires how entire societies relate to one another. People exposed to combat during the first six years of life display lower levels of interpersonal trust and social engagement well into adulthood. Citizens of post-conflict areas are less willing to trust each other, less trusting of institutions, and more pessimistic about the honesty of politicians.
This matters because trust is the foundation of functioning governance. When social capital erodes, communities struggle to organize collectively, support democratic institutions, or rebuild effectively. Research on World War II found that these effects last a lifetime for those exposed in early childhood, shaping their social behavior decades after the conflict ended.
There is a counterpoint worth noting. Some studies have found that post-war communities show increases in cooperation and political engagement, possibly because people who survived together developed stronger in-group bonds or relied on mutual aid as a form of social insurance. The picture is complex: war can simultaneously strengthen bonds within tight-knit groups while destroying broader societal trust. The path a society takes after conflict, toward recovery or prolonged dysfunction, appears closely tied to which of these dynamics wins out.