Traditional pumpernickel bread is made with coarsely ground rye flour (and perhaps some wheat flour) and is fermented with sourdough starter. The acetic acid from the starter and the soluble fibre in rye keep the glycemic load (GL) of the bread low—much lower than that of white or even whole wheat bread.

Why is pumpernickel bread so dark?

Loaves of true pumpernickel undergo a long, slow bake (up to 24 hours); the dark color comes from a browning reaction that takes place in the dough during that time. ... (Less-traditional pumpernickel bread relies on molasses for its color and flavor).

Is pumpernickel bread better for you than regular bread?

A major health benefit derived from consuming pumpernickel bread is that the starter's acidic acid and the soluble fibers of rye keep the bread's glycemic load quite low. Unlike bread made with wheat, when you eat pumpernickel bread, you consume much fewer carbohydrates.