But, not all starch is bad for you… even if you’re on a low-carb diet.  Which brings me to the topic of this article. Resistant starch.

So what the heck is resistant starch (RS)?

Resistant starch… as the name would suggest, is a type of starch that’s not easily digested.  In fact, after you ingest RS, it passes through your stomach and small intestine undigested until it gets to your large colon. In this sense, RS acts very similar to soluble fiber.

And much like soluble fiber, studies show that RS helps improve overall digestive health and bowel regularity.

Resistant starch as a prebiotic

In terms of digestive health, resistant starch is perhaps most useful for its role as a prebiotic.

Prebiotics and probiotics have become hot health topics in recent years- yogurt, fermented beverages, and even packaged goods are now touting their pre and probiotic content to attract consumers.

Natural pre and probiotics have impressive health benefits. That being said, you should be wary of pre and probiotics added to foods (such as granola bars), as they are less likely to act in the same way that natural pre and probiotics do.

So what do pre and probiotics do, exactly?  Probiotics are healthy microorganisms in the gastrointestinal tract that provide protection against harmful bacteria. Prebiotics feed probiotics, supporting their functionality in the digestive tract.

Studies have shown that probiotics are useful in treating irritable bowel syndrome (IBS), diarrhea (especially after a course of antibiotics), urinary tract infections, and aid in the prevention and treatment of vaginal yeast infections.

Types of resistant starch

There are four different types of resistant starch:

Type 1 – Found in legumes, seeds, and grains. This type of resistant starch resists digestion because it is bound within the fibrous cell walls.

Type 2 – This is found in a number of starchy foods, including green (unripe) bananas and raw potatoes.

Type 3 – This type of resistant starch is formed during the cooking and cooling process of certain starchy foods like rice and potatoes. The cooling process transforms otherwise digestible starches into resistant starches.

Type 4 –  Chemically synthesized type of resistant starch

Although there are 4 different types of RS, it’s important to know that any mixture of the first 3 types of resistant starch can be found in the same food.

How does resistant starch benefit our digestive health?

Resistant starch is beneficial to our digestive health because it provides nourishment to your friendly, beneficial bacteria in your gut.

Resistant starch ferments once they reach the intestinal bacteria and produces butyrate which is a short-fatty acid that helps improve the overall intestinal environment.  And because of the slow fermentation process, resistant starch produces less gas than other fibers, so you can avoid being gassy after you eat it.

There are hundreds of different species of bacteria in the intestine and researchers have found that resistant starch not only serves as nourishment for the friendly bacteria in the intestine, but it also helps increase them. And this case more is definitely better… not only for you colon but for your overall health.

The benefits of butyrate for an improved digestion

When we eat resistant starch, it travels to our large intestine and here the bacteria turns it into short-chain fatty acids.  And the most beneficial of these short chain fatty acid, because it’s fuel for the cells that line your colon.  This in turn improves the health of your colon, which helps reduce inflammation of your colon thereby lowering your risk of colorectal cancer.  It also shown to help other inflammatory colon diseases like Crohn’s disease, ulcerative colitis and irritable bowel syndrome.

Other benefits of resistant starch

While resistant starch acts as fiber to aid waste removal and improves digestive health as a prebiotic, it also plays a vitally important role earlier on in the digestive process.  Resistant starch can aid weight loss and weight maintenance by increasing satiety- the feeling of fullness that you experience after eating.

Low fiber foods (ie. refined grains) are digested rapidly, leaving you hankering for another snack soon after your eat, while high fiber foods, take more time to be broken down, slowing the digestive process and helping you feel fuller, longer.  Since resistant starch acts like fiber, consuming resistant starch acts in the same way and helps prevent unnecessary snacking.

Sources of resistant starch

As mentioned above you can get resistant starch from raw potatoes, green bananas, plantains, cooked and cooled potatoes and cooked and cooled rice as well as cooked and cooled legumes.

You can also get resistant starch from supplementary sources like raw potato starch, plantain flour, green banana flour and cassava starch.

As far as getting enough resistant starch, if you’re consuming adequate amounts of soluble fiber and you’re eating a sensible diet based on whole foods and low in refined carbs - you really don’t need to worry about your colon health.

However, now that you know the benefits of resistant starch, it may be worth including foods rich in resistant starch into your weekly diet.  Here’s a couple of suggestions…

• Make potato or bean salad from cooked and cooled potatoes or beans.  It’s great way to include potato and/or beans in your diet without feeling guilty!

• You can throw in a green banana, along with your choice of berries, whey protein and mix it up with coconut milk, almond milk or water for a nutrient packed post workout shake.