Here is everything (pretty much) you’ve always wanted to know about Resistant Starch (in a nut shell).
What is Resistant Starch?
The short version is that resistant starch is starch that escapes the digestion process in the small intestine.
First the Science:
Starches come from carbohydrates. These starches are long chains of glucose that are digested in the small intestine then used as short-term energy OR stored as fat. But not all starches are digested by the small intestine. These special starches RESIST digestion. (In essence they act like dietary, insoluble fiber)
There are 4 types of Resistant Starches (RS):
Type 1: Found in grains, seeds and legumes
Type 2: Found in starchy foods (raw potatoes and green unripe bananas or high amylose corn)
Type 3: Formed when certain foods are cooked then cooled (potatoes, rice, pasta-salad or sushi rice (cooling turns “digestible” starches into resistant starches)
Type 4: Man-made, synthesis starches (not found in nature)
But here’s the great news: The RS works like insoluble fiber and FEEDS the gut bacteria. When these bacteria eat the resistant starch, they form gases and several different short-chain fatty acids, one of which is called BUTYRATE1. Butyrate is the best fuel for the cells of the lining of your intestines.
You’ll never guess but what do you think has the highest concentration of butyrate?
Hint: the Greek word for butter is butyrate.
Now before you go off to drown your baked potato in a pound of butter for lunch, let me tell you that the best source of butyrate is actually what gets fermented in your gut.
Adding more butter to your diet helps but it’s not the main way to increase butyrate content to the colon.
So why is this resistant starch so important?
More studies are showing that these starches are beneficial to the body:
In some studies this has shown to improve insulin-sensitivity. (Being insulin resistant has played a huge role in serious diseases including metabolic syndrome, Type 2 diabetes, obesity and cardiovascular disease.)
Newer studies are also showing that resistant starch may be useful for various digestive disorders. This includes inflammatory bowel diseases like Ulcerative Colitis and Crohn’s Disease, constipation, diverticulitis and diarrhea2
Now you have 2 great reasons to enjoy rice, potatoes (and don’t forget the butter)!
1 Butyrate Improves Insulin Sensitivity and Increases Energy Expenditure in Mice, Zhanguo Gao, et.al.,David L. Topping, Peter M. Clifton, Physiological Reviews Published 1 July 2001 Vol. 81 no. 3, 1031-1064 DOI:
2 Curr Issues Intest Microbiol. 2000 Mar;1(1):25-37., Starches, resistant starches, the gut microflora and human health.,Bird AR, et.al.