It would defy the principles of physics and biology, but an argument could be made that Carole Marks, the 70-something host of the syndicated “A Touch of Grey” radio program, is actually getting younger.

In 1990, Marks started the show, which focuses on “the lives of the 50-plus generation as meaningful, fulfilling and productive as possible,” after recognizing that there was a serious dearth of radio programming aimed at folks over 50 and settling into their retirement years.

From the home studio in the living room of her Mystic residence, between taping phone interviews with a psychologist and a bestselling author, Marks seems, while absolutely focused on the work at hand, pleased to discuss with guests the momentum of her later-life radio career.

“When we started, I’d taken note of seniors who were volunteering for various civic projects, as well as people in their 80s and 90s at retirement homes who were just extremely active and vibrant,” Marks says. “And I thought, with improvements in medicine and health care, it’s a whole different world for people who are getting older. I thought it was a great opportunity for a radio program.”

Marks’s program was initially called “Senior Focus” and originated from the WSUB studio in New London —with a self-engineered financial twist. “I didn’t want the tradional arrangement,” she says. “My idea was that I’d sell the advertising for my own show and split it with the station.”

Marks’ concept worked in a big way.

She says, “I just knew (the show) was something that was needed and I’d never understood was how our country has always been so focused — as far as getting ads and doing things – on the young.

“Guess what? I got advertising on my radio show that would never be on a radio show. Peole didn’t look at it in

that proactive way. I had Drugstores, ambulance associations, exercise and nutritionists advertised, all the way to funeral homes and monuments.”

Over 23 years, “A Touch of Grey” has become a syndicated program reaching over 50 stations nationwide. John McEnroe, Jill Clayburgh, Donna Mills, Mary Chapin Carpenter, Billy Joel and Suzanne Sommers have all recently guested, and favorite topics of discussion range from the cost of prescription drugs and the future of Social Security and Medicare to retirement planning retirement and the best ways to choose a nursing home.

The business has expanded, too. Marks is now CEO of Focus Communications, which oversees “A Touch of Grey” and its tangential interests, and the company recently acquired TALKERS magazine, the leading trade publication in the fields of talk radio and talk television.

While such a schedule would seem overwhelming — perhaps even to a recent college grad or a 20-something entrepreneur — Marks seems absolutely charged by the work and her mission.

She says, “I do have a passion for this. There are important issues. The most important thing that older Americans need to know, since we’re all going to be living longer, is that ability to adapt and change.” She smiles. “And I think it’s not such a terrible thing if the generations come together and work together.”