Lexlee Hudson, 24, has lost nearly 190 pounds, while her mother, Heather, has lost 70 pounds.
They were both inspired by another family member, Lexlee's grandmother, Tish, who lost around 75 pounds following Optavia, a diet plan that claims to help change unhealthy habits into healthy ones.
The mother-daughter duo said they also turned to Optavia to guide their weight loss after being inspired by Tish's success.
"We really just rallied behind each other and empowered each other," Hudson said Friday on "Good Morning America." "It’s so fun to do this together."
Hudson, who is featured in People magazine's 2021 Half Their Size issue, said she had struggled to lose weight for years, relying on diets that were short-lived.
"I dieted and diets, they die," she said. "They're not sustainable because you live in a restrictive reality, and then when it's done, you're done."
Motivated by her mother and grandmother, Hudson started on Optavia at the beginning of 2018 and focused on eating consistent meals and snacks throughout the day and making healthier swaps for her favorite foods.
Her mom, Heather, said that in addition to diet and exercise, she took on a positive attitude and focused on small goals.
"I set small goals for myself that are achievable but they’re challenging, and when I reach those goals, I say, ‘OK girlfriend, what’s next?'" she said. "This is a lifelong transformation. We create one healthy habit at a time. There’s always room for a better version of ourselves and there’s always a next level."
Since losing weight, Heather and Hudson have opened a hip-hop fitness studio together.
Tish, 66, ran her first half-marathon in March, according to Hudson.
We’re breaking generational curses," she said of her family's transformation. "We’re changing the trajectory of our future."