BOSTON, (Reuters) – Massachusetts approved the  toughest statewide restaurant menu labeling rules in the United  States yesterday, requiring major chain restaurants to  display the calorie content of the food they sell.

The regulations, designed to combat rising obesity, are  more comprehensive than those in California, which in September  became the first state with menu labeling rules for fast-food  restaurant chains such as McDonald’s Corp and Yum Brands’ KFC,  advocates of healthy foods say.

Approved by the Massachusetts Public Health Council, the  rules will require restaurant chains with 20 or more in-state  locations to post calorie counts next to each item on their  menus or menu boards, including those at drive-throughs.

The requirements take effect Nov. 1, 2010, and will apply  to 50 restaurant chains with a combined 5,800 locations.

“This is a major step in the right direction in fighting  the obesity epidemic in our state,” Massachusetts Department of  Public Health Commissioner John Auerbach said in a statement.

More than half of the adults in Massachusetts are  overweight or obese, according to a 2008 state report that also  showed adult obesity more than doubling in 20 years. About 33  percent of Americans are overweight, while more than 34 percent  are obese, according to U.S. government figures.

A restaurant calorie information rule took effect in New  York City last year, and more than a dozen states are  considering similar provisions.

Unlike California, the Massachusetts regulations will cover  items at restaurant drive-through windows. About 65 percent of  fast food is purchased at drive-through windows, said Judy  Grant, campaign director of the healthy food advocacy group  ValueTheMeal.org.