Danica McKellar's simple trick to beat holiday weight gain at 50

Danica McKellar is looking fit at 50, and the Great American Family star recently divulged her secret to avoiding holiday - or any time of the year - temptations.

"The Wonder Years" alum also said she doesn't do New Year's resolutions.

WATCH: DANICA MCKELLAR'S TIPS FOR AVOIDING FOOD TEMPTATIONS AND STAYING FIT AFTER 50

McKellar also just published her twelfth math book last month - a children's book called "I Love You 100: A Counting Book Full of Love."

"It's fun when you write your own Christmas movie," she said. "You get to put in the themes that you want. So, you'll see themes of listening to God and forgiveness, which is great around the holidays because of what Jesus did for us."

On location, the 50-year-old actress said she keeps an instant pot in her hotel room, "and I make my own chicken. I bring a rice cooker, I make my own brown rice, I steam vegetables, a little salt, pepper, olive oil. It's so good, it's very tasty, and it's very healthy."

WATCH: DANICA MCKELLAR MAKES HER CHRISTMAS MOVIE WRITING DEBUT WITH NEW GREAT AMERICAN FAMILY FILM

She said that helps her "resist the urge to eat the bad stuff. And when I am resisting the urge, because, believe me, I have temptations, I think to myself - this is my other secret. I think to myself, right now is when I'm earning all the things I love about feeling good and feeling fit and healthy. Right now, I'm earning it."