Is corn starch a resistant starch?

Yes. High amylose corn starches are resistant starches that are not digested.

Let me clarify. Most corn starch comes from dent corn and is highly digestible. Cornstarch is nothing more than chains of glucose. Long, linear chains are called amylose and highly branched, tree-like chains are called amylopectin. Regular corn has about 70-75% amylopectin and 25-30% amylose. Raw, uncooked regular cornstarch contains a lot of resistant starch, but once you cook it, it becomes highly digested.

In contrast, some corn is naturally rich in amylose and contains about 70-75% amylose and only 25-30% amylopectin. The gelatinization temperature of high amylose corn is higher than most baking - so it retains its resistant starch content through baking. It is possible to blast apart high amylose cornstarch through cereal manufacturing or retort processing.

Natural, high amylose resistant cornstarch has been available for many years (Hi-maize brand name) and researchers have been investigating its health properties. To date, more than 70 published human clinical trials have been published in the peer-reviewed scientific literature showing that high amylose resistant corn starch increases satiety so that you can eat less food without feeling hungry, improves insulin sensitivity, shifts your metabolism to burning more fat instead of carbohydrates as energy, and promotes a healthy digestive system.

High amylose resistant corn starch is a specialty starch. The vast majority of cornstarch is NOT resistant starch. You have to look for the specialty hybrid to get the resistant starch benefits.