Dietary Fibre
Have you noticed how, after having a minute of fame, popular health and dietary trends get roundly debunked and filed under “things people used to believe before we got smart”? From low fat to very high fat, to grazing to fasting and everything in between.
One such recommendation is adequate dietary fibre (BORING!). It’s not as sexy as intermittent fasting, bullet-proof coffee, or that whole “paleo” thing (remember that?), but for all the conventional wisdom that I ignored from my mother (sorry Mom…), it is by far the most useful and has absolutely stood the test of time.
What exactly is fibre:
Fibre is made up of the indigestible parts of plants, which pass relatively unchanged through your stomach and intestines. These are fundamentally non-nutritive compounds that play a very special role in our health.
There are two types of dietary fibre, and one honorary runner-up:
Soluble Fibre:
Soluble fibre is found mostly in plant cells. The best sources are fruits and vegetables, oat bran, flaxseed, psyllium, (more on this later) dried beans, lentils, peas. It normalises stool in cases of both constipation and diarrhoea. This probably sounds counter intuitive, but it does this by absorbing fluids into itself, thus bulking up the stools for easier passage through the intestines.
Insoluble Fibre:
As the name suggests, this type of fibre does not absorb water, but it does bulk up the stool to help with constipation. It passes essentially unchanged through the small intestine, as it plays its starring role in the large intestine. It can also be found in plant sources such as nuts, beans, seeds, and the skins of fruits and vegetables.
Resistant Starch:
As you’ve likely guessed, this form of starch resists digestion in the small intestine, arriving intact in the large intestine, ready to be fermented. Although not technically a fibre, resistant starch plays an important role in the maintenance of proper gut health. Resistant starch is found in plantains and green bananas, white beans and lentils, and, interestingly, cooked and cooled rice or potatoes. Even leftover pasta in the fridge has a lot of this starch.
Prebiotic
We hear a lot about probiotics, but what are prebiotics? These are compounds that act as foods for your microbiome, and their number one preferred food source - as I’m sure you’ve guessed - is fibre. Much of the action of the various fibres happens in the large bowel, where it ferments and acts as fuel for healthy gut flora.
By digesting the fibre, these microbes produce health-promoting compounds that help reduce inflammation, protect your colon health, and heal your gut lining. They also help promote the growth of good bacteria while limiting the growth of bad bacteria. This is something that should concern us all, as gut dysbiosis (imbalance between good and bad gut bacteria) is associated with not only gastrointestinal inflammatory disease, but also metabolic conditions, neurological, cardiovascular, and respiratory illnesses.
Other health-promoting benefits:
Reducing cholesterol
Balancing your blood sugars
Balancing your hormones
Reducing your risk of cancer, heart disease, and diabetes
Eliminating toxins
Supporting a healthy gut microbiome.
Maintenance of healthy weight
How to incorporate more fibre into your diet:
Ideally, you should be consuming no less than 30 grams of fibre per day. As I mentioned above, the best sources are obvious: fruit and vegetables (minimum 5 servings per day), nuts and seeds, whole grains, legumes, such as peas, beans and lentils, and dietary fibre supplements. One of the easiest sources of resistant starch is leftover potatoes, or refrigerator oats.
Fibre supplements:
If you struggle with getting enough fibre, you're not alone. Most Canadians have a woefully inadequate fibre intake, possibly explaining the increased incidence of inflammatory diseases. Even if you do eat a largely plant-based diet, it’s not a bad idea to add a small amount of extra fibre to your daily regimen. Here are a few to consider.
Inulin: A soluble fibre which easily dissolves in water, tea, juice or coffee
Psyllium husk: Also a soluble fibre, however, this one will absorb the water, and become a solid very quickly. It’s often used in recipes as a binding agent for this reason. If you take psyllium husk, it should be mixed with a tall glass of water, whisked quickly and immediately consumed, before it becomes too thick to drink. Follow it up with a second glass of water. It has the properties of absorbing fluid in your gut, which is why it works so well for constipation, so make sure you drink enough water with it to ensure it doesn’t cause constipation as a result.
When adding fibre, go slowly. A lot all at once can cause gas, bloating, indigestion and pain, so don’t get too enthusiastic and do it all at once (although I do admittedly appreciate enthusiasm for a high fibre diet). Slow gradual change over time will always work better.
One great resourse I always recommend for my patients is a visit with Dr. Ashley Damm, ND. You can check her out here.
If you have questions about this or any other health topic, please email me here and we’ll get you booked in for a 15 minute discovery call. I’m always available for a chat.
