Preheat oven to 375 F
In a large bowl, whisk together the flours, baking powder, baking soda and nutmeg.
In a second bowl, whisk together the oil, brown sugar, eggs and buttermilk.
Add the wet ingredients to the dry and mix to combine.
Fold in the carrot, zucchini, raisins and zest.
Spoon batter into a parchment lined loaf pan.
Bake in a preheated 375 F oven for 20 minutes. Reduce heat to 350 and bake a further 40 minutes or until a wooden skewer comes out clean.