General Mills, Fiber One 90 Calorie, Mint Fudge Brownies, 6 Count, 5.34oz Box (Pack of 3) Fiber is a "Onederful" thing. Just the facts: Fiber can help keep your digestive system on track. Go ahead--a Fiber One 90 Calorie Mint Fudge Brownie is only 90 calories. A healthy lifestyle shouldn't mean a compromise on great taste. Fiber One 90 Calorie Mint Fudge Brownies are moist, rich, chocolatey brownies with chips and a luscious drizzled topping. Each brownie is 90 calories and 20% of the daily value of fiber (three grams of total fat per brownie).