Green bananas, potato starch, and day-old beans and rice: carbohydrate superstars?

Many therapeutic and weight-loss diets share one common component: a low daily intake of carbohydrates. However, researchers and clinicians are finding that not all carbohydrates are created equally. Making news in the medical and biochemical research communities is a specific kind of carbohydrate that cannot be digested by human beings: resistant starch. You can find resistant starch in many foods, including unripe bananas, potato starch, etc.

Research has broken down the types of resistant starch into four categories:

  1. RS1: From whole and partially milled grains
  2. RS2: Found in unripe bananas, potatoes, and legumes
  3. RS3: Made by heating and cooling rice, pasta, potatoes, and corn
  4. RS4: Commercially made from RS3

If one of our goals is to increase digestion and absorption of the foods we eat, then why eat RS? Although we cannot use RS for fuel, our intestinal bacterial cells CAN. In short, our colonic cells use resistant starch to produce short-chain fatty acids, the most notable of which is butyrate. Butyrate, in addition to being the preferred energy source for these cells, has been shown to decrease inflammation, improve insulin resistance, improve stress resistance, and increase metabolism. It is currently being studied for its possible beneficial effects on conditions such as ulcerative colitis, Crohn’s disease, metabolic syndrome, type II diabetes, and other diseases.

A delicious way to incorporate resistant starch into your diet is by whipping up some plantain pancakes. Check out this recipe for plantain pancakes.

An increase in resistant starches may not be for everyone. Check with your physician before adding these starches, or making any significant changes, to your diet.


Stephan Guyenet. Butyric Acid: an Ancient Controller of Metabolism, Inflammation and Stress Resistance?  Whole Health Source.  December 2009.

Written by Kaitlyn Pote, NCNM Naturopathic Medicine Program

Edited by Dr. Elise Schroeder