The 50-year-old Australian actress and comedienne, who is best known for playing Sharon in Kath and Kim, said that losing more than 20% of her body weight was a "challenge" but had been worth every minute.
Szubanski told New Idea magazine: "[Maintaining a healthy lifestyle] is a lifetime project for everyone. Sometimes it's a bore and a chore but, you know, the feeling of being fit is incredible. You just have to keep plugging away, learning new tricks to keep yourself motivated.
"It kind of goes in waves, but eventually the troughs get smaller and the peaks... well, they are amazing."
Sbuzanski's representative recently admitted that she has gained a "little bit of weight" in the last few weeks, but insisted that she is still enjoying a healthy diet and lots of exercise.
The star has ended her role as the ambassador for weight loss company Jenny Craig. Bridesmaids actress Rebel Wilson has agreed to take over the role, and Szubanski told her: "I wish [her] health and happiness. Go girl."