Soldiers involved in fighting in Iraq and Afghanistan can often develop post-traumatic stress disorder (PTSD) afterwards but some people seem to be more resilient than others. Researchers from the Naval Health Research Center in San Diego surveyed the mental and physical health of 5,410 servicemen before and after combat duty in Iraq or Afghanistan. They found that those who had the worst mental health beforehand were three times more likely to develop PTSD than the rest of the participants. Those with the worst physical health were also more at risk being twice as likely to develop PTSD.
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