The Oscar winner has given up her favourite foods and turned to snacking on fruit as she battles to slim down - and MacLaine admits taking her dog on hikes has made all the difference in her quest to shed the pounds.
She tells Britain's Woman & Home magazine, "I'm on a diet for the first time in my life. All my attention is focused on my tummy, which is too big. I could eat sweets all day but I've made a commitment to myself to lose weight, so that means cutting out chocolate and eating more fruit.
"I hate exercise as much as anyone but when I'm hiking with my dog Terry it's not so bad. I'll do an hour in the morning, then feel like I've earned a nice lunch."