Unlike typical carbohydrates which are digested and turned into glucose within a certain time frame depending on the type of carbohydrate that it is, resistant starch doesn’t behave that way.  Instead it acts like an indigestible fiber and “resists digestion”.  Resistant starches are made of amylose and don’t get digested in the stomach or small intestine and reach the large intestine (colon) intact.  And since they are digested more slowly, they are less likely to spike glucose or insulin.  Once in the colon, resistant starch is turned into energy boosting, inflammation fighting short chain fatty acids such as butyrate by intestinal bacteria.  Butyrate is a preferred energy source for colonic cells and increases our metabolism and decreases colon permeability so that toxins don’t enter your bloodstream.  Increasing other short chain fatty acids (SCFAs) such as acetate, and propionate in addition to butyrate, also stimulate blood flow to the colon, increase nutrient circulation, inhibit the growth of pathogenic bacteria, promote the growth of good bacteria, and help us absorb minerals. 

Examples of resistant starches

Corn, beans and legumes, tubers, white and sweet potatoes, carrots, un-ripened bananas and plantains, winter squashes, rice, and grains.  Technically it could be divided into four groups.