Resistant Starch

This is a continuation on the topic of prebiotics and probiotics. Resistant starch is another healthful component of fibre-rich foods that is receiving a lot of research interest currently.

What is resistant starch?

Resistant Starch refers to carbohydrates that resist digestion and absorption in the small intestine and instead ferment in the large intestine. During this process of fermentation, resistant starch acts as a prebiotic, feeding our healthy gut bacteria. By-products of the fermentation of resistant starch include postbiotics such as the short chain fatty acids~ butyrate, acetate and propionate.

Short Chain fatty Acids

These short chain fatty acids are associated with a range of health promoting effects:

Major fuel source for our colon cells

Enhance intestinal barrier function

Support mucosal immunity

Energy metabolism

Anti-inflammatory

More generally, resistant starch as a dietary fibre, improves gut transit time, may assist in weight management through improved satiety, lowers blood cholesterol by binding bile acids and increasing excretion and supports healthy blood glucose levels. Higher intakes of dietary fibre are associated with reduced colon cancer incidence.

Emerging research is also investigating and highlighting the role these metabolites play in modulating neuro-immunoendocrine factors via the gut-brain axis. Basically, looking at the link between a happy gut and a happy mind!

How to increase the production of short chain fatty acids

To increase the production of short chain fatty acids that your gut bacteria produce, increase your intake of fibre-rich foods, high in resistant starch!

Good food sources include:

Green bananas

Beans, peas, lentils

Oats, barley

Cooked and cooled rice, pasta, sweet potatoes, pumpkin and other starchy vegetables

With the beautiful variety of in-season starchy, root vegetables available, it's easy to increase your dietary intake of resistant starch foods. Just cook extra quantities, let it cool overnight and throw in to salads the following day. Soups are also a great way of increasing your dietary intake of these healthful foods at this time of the year!

References

Whitney E, et al. Understanding Nutrition. 4th Ed. 2019 Cengage Learning, Aus.

Skonieeczna-zydecka K, et al. Faecel short chain fatty acids profile in Polish depressive women. Nutrients. 2018; 10:E1939

Paradore Silva Y, et al. The Role of short-chain fatty acids from gut microbiota in Gut-Brain communication. Front Endocrinol.31 Jan 2020

Liu H, et al. Butyrate: A double-edged sword for health? Adv in Nutrition. 2018; 9(1):21-29