1. No access to prescription medication
2. Illness from poor water
The human body can live without food for a week without damaging the body. After a week however, people become desperate and mentally unstable and physically weak.
It is rare that a foreign nation takes advantage of an economic collapse and invades another nation because its military cannot function well inside a nation that is bankrupt and the populace is out of control.
For More... http://www.bigjohnlipscomb.com