Suzanne Somers, who gained fame by playing a ditsy blonde on the sitcom “Three’s Company” and then by getting fired when she demanded equal pay with the series’ male star — and who later built a health and diet business empire, most notably with the ThighMaster — died on Sunday at her home in Palm Springs, Calif. She was one day away from turning 77.
The cause was breast cancer, Caroline Somers, her daughter-in-law, said.
“Three’s Company” first went on the air in 1977. The show told the story of two roommates — Chrissy Snow, a secretary, played by Ms. Somers; and Janet Wood, a florist, played by Joyce DeWitt — who welcomed a man to join them as a third roommate: Jack Tripper, a culinary student played by John Ritter. Since their landlord would frown on an unmarried man living with two single women, the group pretended that Jack was gay.
High jinks ensued. The show featured slapstick comedy, lighthearted misunderstandings and jokey one-liners.
By the show’s fifth season, “Three’s Company” was one of the nation’s most popular sitcoms. Ms. Somers’s acrimonious contract negotiations with ABC became news. In 1982, The Times reported that she had wanted a raise to $50,000 from $30,000 an episode. In recent years, Ms. Somers repeatedly said that she had sought $150,000, in line with Mr. Ritter’s pay.
She did not get the pay increase. Instead, she was fired.
“I’ve been playing what I think is one of the best dumb blondes that’s ever been done, but I never got any credit,” she told The Times that year. “I did it so well that everyone thought I really was a dumb blonde.”
Ms. Somers’s first notable role came in the 1973 film “American Graffiti.” She appeared only briefly, mouthing “I love you” to one of the stars, Richard Dreyfuss; the credits listed her as “Blonde in T-Bird.”
But that scene was beguiling enough to earn her a spot on “The Tonight Show” with Johnny Carson, who, Ms. Somers recalled earlier this year in an interview with Page Six, introduced her as “the mysterious blonde in the Thunderbird from ‘American Graffiti.’”
Appearing on “The Tonight Show,” she said, got her the audition for “Three’s Company.”
In the years after “Three’s Company,” Ms. Somers remained recognizable for frequent appearances in movies and on television, including the 1990s sitcom “Step by Step,” a stint co-hosting the television series “Candid Camera” and a wide variety of talk shows.
But her later reputation sprang from her business acumen — which proved to be more formidable than ABC’s executives appreciated in 1980.
She and her husband, Alan Hamel, made the ThighMaster, a workout device, one of the most recognizable products in infomercial history, thanks in part to Ms. Somers’s many leggy appearances alongside the product. The ads showcased her beauty and her advice that is “it’s easy to squeeze, squeeze your way to shapely hips and thighs.”
More than 10 million units of the ThighMaster have been sold over the years at an average price of about $30, Caroline Somers said. She is not only Ms. Somers’s daughter-in-law but also the president of her mother-in-law’s company, which owns the ThighMaster and has overseen Ms. Somers’s other business and entertainment activities.
In the mid-2000s, Ms. Somers was appearing on the Home Shopping Network for more than 25 hours every month. She was the pitchwoman for everything from cowboy boots to waffle irons.
Ms. Somers also wrote more than 27 books, including 14 best sellers, which tended to focus on issues related to the body and aging.
Some of the methods she promoted — particularly bioidentical hormone replacement therapy, a treatment that she called “the juice of youth” for menopausal women — have often been criticized by doctors as unproven and possibly unsafe, even as the market for them has grown.
The foundation of her business efforts was the sex positivity that she had embodied since “Three’s Company.”
“A sexual person,” she told The Times for a profile in 2020, “is a healthy person.”
Suzanne Marie Mahoney was born on Oct. 16, 1946, in San Bruno, Calif. Her father, Francis, had some success as an athlete but not enough for a lasting career, and he spent much of Suzanne’s youth working at a brewery. Her mother, Marion (Turner) Mahoney, was a medical secretary.
Suzanne Mahoney was kicked out of a Catholic high school when nuns discovered love letters she had written. She graduated from Capuchino High School, a public high school, in San Bruno.
She attended Lone Mountain College (which later became part of the University of San Francisco), but she dropped out after she discovered in 1965 that she was pregnant, and she married the baby’s father, Bruce Somers, days later.
They divorced in the late 1960s. Not long afterward, she worked as a prize model on a game show hosted by Alan Hamel, a frequent TV host. They quickly began dating and married in 1977.
In addition to Caroline Somers and Mr. Hamel, Ms. Somers is survived by Bruce Somers, her son from her first marriage; two stepchildren, Stephen and Leslie Hamel; two siblings, Maureen Gilmartin and Dan Mahoney; two granddaughters; and four step-grandchildren.
Ms. Somers was first diagnosed with an aggressive form of breast cancer more than 20 years ago. She pivoted from selling mainly jewelry, apparel and weight loss and diet products to focusing on organic skin care and cleaning goods, along with her promotion of hormones.
She managed to sustain an energetic calendar of live performances. An autobiographical show on Broadway, “The Blonde in the Thunderbird,” was critically panned and closed after only 15 performances, but she had better luck in Las Vegas, where she enjoyed many years of song-and-dance gigs, featuring flamboyant costumes and no small amount of glitter.
At the time of her Times profile in 2020, Ms. Somers had recently fallen from the private tram on her 93-acre compound in Palm Springs while partying with friends. Yet a reporter observed her at a spa in New York City managing the feat of walking with “a vampy strut” even while using crutches.