Preheat oven to 350°F (175°C). Grease and flour a 9x5 inch loaf pan.

In a large bowl, whisk together the flour, baking soda, cinnamon, nutmeg, and salt.

In a separate large bowl, cream together the softened butter and sugar until light and fluffy. Beat in the eggs one at a time, then stir in the vanilla extract.

In a small bowl, combine the buttermilk and the peaches.

Gradually add the dry ingredients to the wet ingredients, alternating with the buttermilk mixture, beginning and ending with the dry ingredients. Mix until just combined. Do not overmix.

Gently fold in the diced peaches.

Pour the batter into the prepared loaf pan. Sprinkle with chopped pecans or walnuts, if desired.

Bake for 55-65 minutes, or until a wooden skewer inserted into the center comes out clean.

Let the bread cool in the pan for 10 minutes before transferring it to a wire rack to cool completely.