Ardath Harter Rodale, 81, of Allentown, former chairwoman of Rodale Inc., died Friday at her home.

In 1942, Mrs. Rodale's father-in-law, J.I. Rodale, started Organic Farming and Gardening magazine, and in 1951 the company introduced Prevention. After he died in 1971, his son, Bob, succeeded him, and expanded the company into a publisher of books and magazines focused on health and fitness.

In 1990, Bob Rodale died in an auto accident while on a trip to Russia. Before he left, one of his executives asked him what would happen to his publications without him. "You'll have to trust Ardie," he replied. "I do."

After her husband's death, Mrs. Rodale became chairwoman. One of her first acts was to push ahead plans for a new day-care center for employees' children. During her tenure, Rodale published The Doctors Book of Home Remedies, which has sold 20 million copies; expanded internationally; and launched Men's Health and New Farmer, the Russian magazine that was her husband's last project.

Mrs. Rodale received numerous honors, including a spot on Working Woman's list of the top 50 female business owners in the United States.

In 2007, when her daughter, Maria, became chairwoman, Mrs. Rodale took the title of "chief inspiration officer."

Rodale's mission, she said on the company Web site, is to show people how they can use the power of their bodies and minds to improve their lives: " 'You can do it,' we say on every page of our magazines and books."

Mrs. Rodale was cochairwoman of the board of the Rodale Institute, whose mission is to improve health through research and education that focuses on organic farming, food, and living.

The daughter of a Mack Trucks Inc. employee, Mrs. Rodale graduated from what is now Kutztown University in 1950. The next year, she and Bob Rodale married.

He did not want her to work, she told an Inquirer reporter in 1991, but she fought to be Rodale's director of environmental resources - planning, renovating, and decorating the companies properties. She began working at Rodale in 1956.

When her son David died in 1985 at 30 of pneumonia brought on by AIDS, Mrs. Rodale began an AIDS awareness campaign, lecturing to students and community groups. She served on the Harvard AIDS Institute's International Advisory Committee.

In 1989, Mrs. Rodale published a memoir, Climbing Toward the Light, and later wrote Gifts of the Spirit, Reflections, and Everyday Miracles. She was a columnist for Prevention.

In addition to her daughter Maria, Mrs. Rodale is survived by son Anthony, daughters Heather and Heidi, a brother, a sister, and 11 grandchildren.

Services have not been set.