What It Is
Tapioca flour is starch that has been extracted from cassava (a starchy tuber) and dried and ground into flour. It’s great for making Paleo baked goods light and fluffy, but not much else.
Pros and Cons
Tapioca flour gets used in Paleo baking because it’s free of antinutrients, but it doesn’t have much in the way of nutrients either. It’s basically a concentrated form of carbohydrates, and whether or not you can handle that level of carbs is entirely individual. Some people can tolerate carbs better than others, and those who are highly active usually need more carbs in their diet than those who are sedentary.
Even Mark Sisson gave tapioca flour a Primal pass.