NEW YORK — Atkins Nutritionals, the company that promoted low-carbohydrate eating into a national diet craze, filed for bankruptcy-court protection yesterday, a company spokesman said.

Atkins has been hurt by the waning popularity of its namesake diet, which focuses on eliminating carbohydrates such as bread and pasta to shed weight.

The diet became one of the most popular in U.S. history, spawning a virtual cottage industry of low-carbohydrate regimens, but drew criticism from experts for its focus on fatty foods and low consumption of fruits and vegetables.

A hearing on the Chapter 11 filing was scheduled for today in U.S. Bankruptcy Court, spokesman Richard Rothstein said.

Dr. Robert Atkins founded the privately held company in 1989. He died in 2003 from injuries suffered in a fall.

Atkins Nutritionals said it had reached an agreement with the majority of its lenders to give them equity in exchange for lowered debt. It owes $300 million in outstanding principal and interest, Rothstein said. The company said it had received $25 million in financing to operate during the bankruptcy proceedings, which it said would not affect day-to-day operations.

Mark Rodriguez, president and chief executive, said the company has in the past year "adjusted our organization to accommodate a smaller business" and will promote its brands "more broadly for consumers who are concerned about heath and wellness."

After it leaves bankruptcy, the Ronkonkoma, N.Y.-based company will focus on its nutrition bars and shakes, Rodriguez said in a statement.