Clean Up with Fibre
Article By: Bridie Williams 13/09/2017
Clean Up with Fibre
Most nutrients you hear about seem to have complex and lengthy uses but this nutrient has a slightly more practical use within the human body. In fact, fibre’s nutritional value seems quite basic at a glance. The majority of Australians know that they need fibre to be regular. On a mechanical level, this is true; unbeknownst to many of us though, there is considerably more implicated in getting enough fibre in our day.
Just to prove that it can be as complicated as the rest of the vitamins, the label “fibre” covers several subcategories. Up until the last few decades though, scientists were unaware of this, so what turned out to be several different types were lumped under the one category.
Firstly, we have insoluble fibre. This is the parts of fruits, vegetables, grains, nuts and seeds that can’t be digested or dissolved. It therefore adds bulk to the stool making it easier to pass.
Then there is soluble fibre which absorbs water as it is digested which means that initially, it slows the emptying of the stomach. This allows for a much slower uptake of glucose from food into the blood as well as making you feel fuller for longer. By drawing water into the digestive system to dissolve these fibres, soluble fibre specifically helps to prevent constipation.
Resistance starches are the most evasive of all the fibres, making it through the stomach and the small intestine without being digested until it finally ends up in the large intestine where it can be fermented and transformed into short chain fatty acids. The importance of these will become clear in the following sections.
Finally, prebiotic fibre, which has become the nutrition buzzword of the year. Prebiotic fibres essentially fall under the soluble fibre label but what makes them so special is their ability to feed the beneficial bacteria of our gut microbiome.
There are two key reasons that fibre can boast an impressive range of health benefits: it gets things moving and it feeds the microbiome.
Let’s face it, fibre is our motility expert.
As we learned from looking at the different types of fibre, it creates a larger and softer stool by contributing bulk and attracting water into the digestive system. The larger stool triggers and sustains gut movement, meaning that the stool will move quicker and more efficiently. Fibre also clears the digestive system of any lingering waste on the digestive system walls, acting as a broom of sorts as it passes through the digestive system. This is the more mechanical side of fibre. The reason that this is so essential is because the stool is a dumping ground for toxins and waste.
The liver filters toxins and waste from our blood and then eliminates them from the body through the stool. The issue here is that if the stool sits stagnant in the digestive system for long periods of time and is not removed efficiently, they can be reabsorbed back into the bloodstream. Fibre can prevent this from happening by binding to the toxins and prevent this reabsorption.
Hormones such as estrogen which are also excreted in a similar process can also be reabsorbed in this manner from a constipated bowel, creating an excess: a common pattern in those suffering from period pain and PMS.
A diet rich in soluble fibre helps to lower unhealthy cholesterol by preventing the reabsorption of it from the gut. Another cardiovascular boon for fibre is that it reduces the accumulation of triglycerides in the body therefor reducing the risk of heart disease by promoting healthy fat metabolism.
Soluble fibre in particular, slows digestion of starch in our foods by slowing the rate at which the stomach empties. As starch is converted into glucose, this means that soluble fibre slows this conversion rate, regulating blood sugar levels.
Think of your microbiome as being a microscopic ecosystem or city that needs to be fed.
Not only does this ecosystem need to be fed, but if they don’t get fed they overreact slightly and start eating away at the proteins holding their environment (the digestive system) together. A happy ecosystem, however, will send out anti – inflammatory signals to the body which is why people with higher fibre intake usually have lower levels of inflammatory markers. These markers are key indicators of chronic diseases such as heart disease, cancer and diabetes.
The bacteria that make up this ecosystem feed on short chain fatty acids which we mentioned earlier. These short chain fatty acids are made in the digestive system by fermenting resistant starches. This supply of food encourages the bacteria to grow but inhibits any foreign growths, a perfect balancing agent.
A healthy and happy ecosystem also allows for the production of neurotransmitters such as serotonin and dopamine (read: your feel-good hormones). These, together with the short chain fatty acids we mentioned earlier, maintain the integrity of the gut “walls” which can easily become permeable. This increases the production of a cell that specifically regulates the immune system, aiding the fight against inflammatory conditions such as asthma, heart disease, diabetes and autoimmune conditions.
The bottom line…
These two key points show just how important dietary fibre is for the prevention of chronic sickness and for the promotion of a healthy body. Putting this in to practice is as simple as ensuring that you get enough fibre in your diet daily. While it is sometimes confusing to know where all the various types of fibre come from, one of the most efficient ways to quickly check whether you are getting enough fibre of each type in your day to day eating is to make sure you are eating a variety of foods from the following list every day.
- Potato or rice, cooked then allowed to cool
- Coconut flour
- Brussel sprouts
- Unripe bananas
- Psyllium husks
Remember: we need at least 5 serves of vegetables and 2 serves of fruit daily to help meet our fibre needs.
This information on fibre is general information only and will not suit all individuals. There are specific health conditions that specifically require a low fibre diet which can only be identified by a qualified health professional. Please seek your health professional for further advice.
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