The advertisements appeared on the back pages of women's magazines and Sunday newspapers, promising such attributes as a fuller bust or a slimmer waist.
The products promoted by Jack and Eileen Feather, major shareholders of Cambridge Plan International, went by such names as the Mark Eden Bust Developer, Astro-Trimmer (a waist reducer) and Slim-Skins (sauna pants that are attached to a vacuum cleaner).
Although Cambridge Plan International President Vaughn Feather protests that there is "hardly any similarity" between the Cambridge diet and his parents' previous ventures, all cater to the consumer's desire to look better.
Jack and Eileen Feather first entered the fitness business in the 1950s, when they opened a chain of Eileen Feather Figure Salons in California and Nevada. In the mid-1960s, the Feathers developed the Mark Eden Bust Developer, a device that looked like an open clam shell.
The U.S. Postal Service proclaimed the Mark Eden Bust Developer and similar Feather products worthless and launched a nearly 20-year legal battle with the Feathers, who sold their products through the mail, said Tom Ziebarth, a lawyer with the Postal Service's consumer protection division who was involved with the Feather mail-fraud cases starting in 1969.
The Feathers ultimately won on appeal all the civil cases brought by the Postal Service, Ziebarth said.
"They kept appealing and they had millions for defense," he said. "In order to win like they could, we had to spend like they did."
In the late 1970s the Postal Service commissioned a study, conducted at the University of Arizona, to determine the effectiveness of the Mark Eden device. The study "found these things were valueless," Ziebarth said.
In 1982, a federal grand jury in San Francisco indicted the Feathers on mail-fraud charges.
The Feathers settled the suit out of court in May, 1983, without admitting guilt. Under the agreement, the Feathers paid the U.S. Postal Service $1.1 million and agreed to stop manufacturing or selling Mark Eden, Slim-Skins and similar devices.
Vaughn Feather described the Postal Service lawsuits as a "vendetta."
"They (the Postal Service) kept losing because we could demonstrate that our products were effective," he said. Even though "there's no question we would have prevailed," Feather said his parents settled out of court because of the estimated $2 million needed for defense and the "media circus" that would have resulted.