Preheat oven to 400°F. Coat a 12-cup muffin pan with cooking spray.
Combine coconut, 2 tablespoons all-purpose flour, 2 tablespoons brown sugar and 2 tablespoons macadamia nuts in a small bowl. Drizzle with 1 tablespoon oil; stir to combine. Set aside.
Whisk the remaining 3/4 cup all-purpose flour, whole-wheat flour, baking powder, baking soda, salt and cinnamon in a medium bowl. Whisk the remaining 1/2 cup brown sugar, the remaining 1 tablespoon oil, egg, egg white, buttermilk, butter and coconut (or vanilla) extract in a medium bowl until well combined. Make a well in the center of the dry ingredients and pour in the wet ingredients; stir until just combined. Add blueberries and the remaining 3 tablespoons nuts; stir just to combine. Divide the batter among the prepared muffin cups. Sprinkle with the reserved coconut topping and gently press into the batter.
Bake the muffins until golden brown and a wooden skewer inserted in the center comes out clean, about 20 minutes. Let cool in the pan for 10 minutes, then remove from the pan and let cool on a wire rack at least 5 minutes more before serving.
No buttermilk? Mix 1 tablespoon lemon juice into 1 cup milk.Source: Look for whole-wheat pastry flour in the natural-foods section of large supermarkets and natural-foods stores. Sources include King Arthur Flour, (800) 827-6836, www.bakerscatalogue.com, and Bob's Red Mill, (800) 349-2173, www.bobsredmill.com.