Australians eat good levels of fibre for roughage but are missing out on resistant starch. Why is resistant starch so important for our gut and what can you do to boost your resistant starch intake today?
What is Resistant Starch?
Resistant starch is found in foods like potato that is cooked and cooled and unripe banana. Most starch are very easily digested in our gut but resistant starch is unusual because it is not well digested, in fact as its name suggests, it resists digestion!
Like FODMAPs, resistant starch remains in the gut and reaches the large intestine where waiting gut microbes are keen to ferment it for their nutrition.
Unlike FODMAPs, which are fermented very rapidly and quickly accumulate gaseous by- products which can trigger symptoms, resistant starch is very slowly fermented by our gut microbes so only slowly release these very healthy gaseous by-products.
How Resistant Starch resists digestion in the gut
Resistant starch can resist digestion due to different reasons. The starch may not be easily accessed by the enzymes in our gut as it may be embedded into the fibrous structures of the plant.
Resistant starch may be formed as a result of being cooked and cooled, which causes a process called retrogradation. This happens with potato that is cooked and cooled as well as rice and pasta.
Some starches are altered chemically in the lab which make them resistant to being easily broken down in the gut and may be used as ingredients in food.
How Resistant Starch good is good us
Fermentation of resistant starch produces beneficial gases in the same way that FODMAPs do. These gases are called short chain fatty acids and are highly beneficial for our gut.
One of these short chain fatty acids produced with the breakdown of resistant starch is butyrate. Butyrate is a nutritional source for our gut cells lining our gut wall and thus promote health and integrity of our gut lining. Butyrate helps increase blood flow to the gut keeping it healthy and functioning.
This super helpful little molecule also helps to detect cells with damaged DNA due to mutations caused by environmental factors which results in the damaged cell self destructing before they get a chance to initiate rectal cancer. Butyrate has been shown to help reduce inflammatory processes.
And these are only the things we know about!
Do we eat enough Resistant Starch?
No - we - don't.
We are great at increasing fibre in our diets and getting our bowels regular but when it comes to resistant starch- we fall down. In fact we fall down in having a diversity of fibres, often relying on the same old sources every day.
According to the CSIRO, Australians are eating between 3-9g of resistant starch daily. This falls well short of recommendations to consume between 15-20g of resistant starch per day.
And.. women are more likely to have less resistant starch than men, and I am thinking this is because women tend to restrict their carbohydrates more than men do.
Given how important resistant starch is for our gut health- we need to understand how to improve our resistant starch intake.
Which Foods are Rich in Resistant Starch?
At this point in time, we do not have resistant starch data in different foods. This is mainly because the amount in food changes depending on processing, cooking method, storage and if it is reheated.
Research by the CSIRO indicates that many foods we eat have low levels of resistant starch, such as
bread
pasta
legumes and beans
nuts
seeds
some starchy vegetables and starchy fruit such as unripe banana.
Potatoes, rice and pasta that is cooked and cooled results in a moderate increase in resistant starch content.
WHOLEGRAIN cereals and grains: this is really, really important so choose brown rice over white rice, wholegrain bread, brown or wholegrain pasta, brown flour, grains such as quinoa and millet
It is probably not a good idea to limit our aim of increasing resistant starch by just having unripe bananas and cooked and cooled potato and rice and pasta.
We need to go wholegrain or choose more coarse grains as wholegrains contain more resistant starch than their more processed white counterparts. Brown rice has more resistant starch than white rice.
We need to choose a much wider variety of foods than we do.
The key is to always, always, always choose a variety of fibres every day. Really making an effort to choose brown rice over white.
To choose wholemeal pasta rather than white.
To choose unrefined foods over refined foods.
To choose different fruits and vegetables and increase the amount of veggies you eat each day (because let's face it, we all could do with more vegetables).
To include nuts and seeds in our diet on a really regular basis.
A healthy gut will always require fibre diversity. To do this choose a variety of different fibre foods every day.
Choose different fibres every day rather than relying on the same type. Diversity of fibre is the key. Choosing wholegrain and wholemeal breads and rice and pasta rather than white, along with a variety of vegetables (eat a lot more vegetables!) and fruit as well as nuts and seeds. This will boost your resistant starch along with all the other different types of fibre our guts need to heal and stay healthy.
References
1. Understanding resistant starch and its role in gut health. CSIRO- nutrition science-nutrition facts. Updated 12 July 2019. Accessed on 3/9/19. Accessed from
2. Is my gut healthy? Eliza Geck, CSIRO blog. 20/9/18.Accessed on 3/9/19. Accessed from
Comments