I believe the benefits are found in the skin. The general rule of thumb for fruits/veggies is the richer or deeper the color (purple, red, orange, green), the higher the antioxidant content. Purple potatoes
are taking the population by storm as well for their health benefits.
Anything that reduces oxidative stress is good for the body, though some stress is preferable. I believe autoimmunity is the result of this mechanism gone haywire (by environment, diet, antibiotics and stress). I don't believe it's all genetics.