Here is another recipe for rutabagas.
1 cup flour
2/3 cup sugar
1/2 teasp baking soda
1/4 teasp allspice, ground
1/4 teasp cinnamon
1/4 teasp nutmeg
1/4 teasp salt or to taste
1/4 teasp baking powder
1/2 cup rutabaga, cooked & pureed
1/4 cup vegetable oil
Spray an 8 by 4 in. baking pan and line with wax paper. Combine
flour, sugar, baking soda, allspice, cinnamon, & nutmeg; mix
well. In another bowl, beat egg and add rutabaga & veg oil. Add
moist ingredients to dry ingredients all at once. Stir just
enough to blend. Pour into prepared pan & bake in preheated oven
at 350 for one hour, or until toothpick comes out clean.
I'm not sure on the fat content but I found the recipe in Fat
Burning Foods and other Weight-loss Secrets. So they usually
have a low fat content and low calories.