MSNBC/Newsweek:

A diagnosis of amyotrophic lateral sclerosis (ALS) is devastating. Victims of this fatal neurological disease lose almost all muscle control, even the ability to breathe on their own. That's why it might seem alarming that a new report from the Institute of Medicine, released today, suggests a possible connection between military service and later development of ALS, also known as Lou Gehrig's disease (after its most famous victim). But the chairman of the committee that wrote the report cautions against overreaction.

[..]The report analyzed five studies that examined a potential link between military service and ALS. Three of the studies focused on Persian Gulf War veterans and found that their risk of developing ALS was as much as two times higher than that of the general population or veterans of the same era (1990-91) who served outside the Persian Gulf. Another study found that veterans who served from 1910 to 1982 had 1.5 times higher risk of ALS. The fifth study found no association.

However, there were methodological problems with several of the studies and Johnson says much more research is needed before scientists can establish a real connection-if there is one. Read on...