Unlike potato starch, potato flour is the whole potato (sometimes including the peel) that has been dried and ground into flour form. This means it has more fiber and more nutrients than potato starch.
The Pros and Cons
Although they’re starchy, potatoes are actually pretty nutritious and they don’t have much in the way of antinutrients (although they are a nightshade and some people are sensitive to nightshades). Not everyone can handle the high starch content of potatoes, but for those who can, the starch offers some distinct health benefits.
Potatoes have something called resistant starch, which is a prebiotic that feeds the beneficial bacteria in our guts. Making sure the good guys are fed helps everything from our digestion to our skin health.
Starch vs. Flour
Potato flour is much thicker than potato starch and doesn’t create the same fluffy texture when used in baking. Because of the resistant starch though, many people use potato flour as a supplemental food. You can throw a spoonful in some sparkling water or a smoothie to get the same health benefits as eating raw potatoes.
Mark Sisson has a whole post on the benefits of resistant starch and how to include it in your Paleo diet.