Resistant Starch
RS Topics

Health Focus

An in-depth review of the benefits of resistant starch for people


Today, there is a large and growing body of research that both demonstrates and suggests a wide range of health benefits for resistant starch from high amylose corn.  This section of begins to review these benefits. The links on the left feature in-depth information on a range of topics. For more information on work that points to health benefits or resistant starch, visit the Clinical Studies section of this website.


Just like not all fibers are the same, not all resistant starches are the same.  Data confirm that different types of resistant starches deliver different benefits.  Thus, benefits demonstrated by high amylose corn resistant starches cannot be extrapolated to other types of resistant starches.  Benefits demonstrated with RS2 and RS3 resistant starches cannot be extrapolated to chemically modified RS4 resistant starches. 


Major benefits of resistant starches from high amylose corn (RS2 & RS3)


Digestive Health


Resistant starch in the diet mildly promotes regularity.  It also lowers potentially harmful compounds such as ammonia, phenols and secondary bile acids.




Resistant starch is a prebiotic fiber.  A prebiotic selectively stimulates the growth and/or activity of beneficial bacteria in the colon.  Fermentation of high amylose corn RS2 by bacteria in the colon has been shown to increase Bifidobacteria and Lactobacillis.  This fermentation increases the production of butyrate, a short-chain fatty acid with many anti-cancer and anti-inflammatory properties.


Glycemic Management


When used to replace flour, resistant starch lowers the glycemic and insulin impact of foods.  In addition, clinical studies have shown that resistant starch increase insulin sensitivity in healthy people by more than 30%.


Energy Management


Eating foods with resistant starch helps balance energy in the hours following a meal because the energy of resistant starch is partially released in the small intestine as glucose and partially released in the large intestine as fermentation by-products (such as acetate).  In addition, when used to replace flour, it lowers the glycemic and insulin response of foods.


Weight Management


When used to replace flour, resistant starch lowers the calorie density of foods, delivering between 2 and 3 kilocalories/gram (8-12 kilojoules/gram) vs. 4 kilocalories /gram (16 kilojoules/gram) for flour.  In addition, eating just one meal containing natural resistant starch can increase the body’s ability to utilize lipids as an energy source. 


Digestive tolerance


Numerous studies have demonstrated that dietary consumption of natural resistant starches are well tolerated. Individuals could consume as much as the recommended daily dose of dietary fiber from natural resistant starches with minimal or no digestive side effects.


The health benefits above have been documented in a growing body of research that includes more than 120 peer-reviewed scientific studies. 


New directions for resistant starch


Early indications show natural resistant starch may offer even more health benefits than those listed above.  While a solid body of evidence is still emerging, the following areas of study demonstrate promise:


Animal studies suggest that RS2 resistant starches increase bioavailability of minerals including calcium.


Animal studies also suggest that dietary consumption of high amylose corn RS2 increases immune function. 


It may also play a beneficial role in colonic diseases such as ulcerative colitis and Crohn’s disease.  


High amylose corn RS2 has been shown to be an effective treatment for diarrhea caused by cholera in adolescents and adults.  It restores intestinal balance by promoting the absorption of sodium. 


Dietary consumption of high amylose corn RS may have a beneficial role in reducing the risk of cardiovascular disease, primarily through its ability to increase insulin sensitivity.  Further research is needed to identify specific mechanisms and extent of the potential benefit.


  Hi Maize