According to California researchers more and more soldiers are returning from active service in Iraq and Afghanistan with post traumatic stress disorder (PTSD) and brain injury.
A study carried out over a 22 month period, on 13,440 soldiers returning home from Afghanistan and Iraq, found 18% of them suffered from brain injury and 25% were diagnosed with post-traumatic stress disorder or other mental-health related issues.
Traumatic brain injury results in severe mental problems caused by strikes or blows to the head.
These two injuries are in fact the most significant injuries being reported when soldiers return home from the wars.
What is more, doctors are predicting that the numbers can be expected to grow as more and more troops return home.
Doctors say that though the military has improved in it's methods of recognising and addressing the issue of mental illness, many U.S. soldiers still do not seek treatment because of the stigma associated with it.
While experts admit there is no cure for memories associated with shocking experiences, there are many things that can help, and the earlier a soldier seeks treatment for PTSD, the better chance they have of recovering from it.
PTSD is an anxiety disorder that can occur following a person experiencing a traumatic event, and people who have seen combat are very susceptible to it.
PTSD symptoms include flashbacks, hyper-vigilance, depression and disturbed sleep patterns; sufferers often require on-going help and support which stretches mental-health resources.
The National Center for PTSD estimates that about 30% of men and women who served in Vietnam have PTSD and 20% of them have had partial PTSD at some point in their lives.
Many experts believe very few involved in combat escape unscathed.