Obesity is often cited as causing a national health crisis, with 35.7 percent of U.S. adults fitting into a category associated with elevated risk of heart disease, stroke, type 2 diabetes and certain forms of cancer, according to the Centers for Disease Control and Prevention.

It also is creating a crisis for employers, who must balance concerns that severely overweight people are more likely to get injured, miss work and drive up group health insurance premiums against the risk of violating the Americans with Disabilities Act (ADA).