October 3rd, 2022
Prebiotics are carbohydrates that are not digestible by humans and that reach the colon intact and thus feeding colonic bacteria. Prebiotics are generally classified into three different types: 1) non-starch polysaccharides such as fructo-oligosaccharides and inulin, 2) soluble fiber such as oats, psyllium husk, hemp and chia and legume fibers, and resistant starch (RS). Each of these prebiotics feeds a different species of bacteria.
Resistant starches when consumed do not spike either blood glucose or insulin after consumption and have no major effect on weight. This makes them a great addition to the diet.
They feed our microbiome but not us since we are not in a calorie deprivation environment.
Resistant starches are chemically interesting as the difference between them and other starches is the starch carbon chain of RS is straight and not branched leaving less digestible surface for amylase to act on. Heating and cooling adds a new layer to it as well.
There are 5 types of RS. I am going to discuss only the type 3 retrograde RS foods. This group of starches has the ability to change conformation through temperature shifts and therefore become indigestible to our metabolic system after they are heated and cooled. The more they are heated and then cooled the more RS is formed.
I think of a blacksmith making a sword. The iron is heated, hammered and then cooled. Repeating the process hardens the metal in increasing degrees of strength. The same appears to be true with the starch of potatoes, rice and soaked legumes.
From the health perspective, giving these RS foods to kids will feed the gut bacteria that we need fed and increase short chain fatty acids like butyrate that feed our intestinal cells known as enterocytes. This is critical to human health folks!
I love Bob's Red Mill unmodified potato starch. Start with 1/4 to 1 tsp daily and work up to 1 Tbsp daily. Some people will experience GI upset and need to take it slow and steady as they right their gut ship. Add it to smoothies or any dish that is less than 130 degrees F. Also consider other starchy foods like unripened bananas, plantains, yams and yucca for RS.
Keep up the charge of changing your child's health and life outcome via food and love. I love this stuff.
From a recent study in Cancer Prevention Research: RS is fermented by multiple human colonic bacteria including members of the Ruminococcaceae, Lachnospiraceae, Erysipelotrichaceae, and Clostridiaceae families that are butyrate producers and involves synergy between primary RS degraders and secondary starch scavengers. Butyrate suppresses cancer cell proliferation and may enhance apoptosis. Antineoplastic effects may also be mediated via microbial modulation of immune homeostasis. This was demonstrated in experimental studies showing differential stimulation of Toll-like receptors and attenuation of proinflammatory cytokines in dendritic cells. (Mathers et. al. 2022)