The Australian actress and comedienne, who is best known for her role in Kath and Kim, said that she feels a "sense of pride" since she lost over 26kg with the help of weight-loss company Jenny Craig.
Szubanski told Woman's Day magazine: "I strongly believe that if you don't have your health, you don't have anything. The whole thing for me about losing weight is, yes, you can wear fantastic clothes but it really is about health, improving your fitness and your enjoyment of life.
"I used to drive... 200m, because I couldn't walk that far easily. How sad is that? It's really hard and demoralising when you get that overweight and that unfit.
"Every day I get the loveliest compliments about the way I look. Feeling good really does make you look good. There is nothing like a healthy glow. When your body is getting the right fuel, you feel a sense of pride that you have taken your life in a really positive direction. And when the body gets what it needs, it is so grateful.
Szubanski added: "I used to be terrible. I never ate vegetables. Now, I honestly love them. Which goes to show there are things you can change about yourself. And it's easy. I still fall off the wagon but I get right back on it again when I do."
Earlier this year, Szubanski said that she finds it "intimidating" being a "role model" because she thinks of herself as "a bit of a flake". She has also said that she used to have nightmares about dying young because of her weight issues.
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