Fibre: The forgotten nutrient
Did you know? More than 60% of people in the Western world lack adequate dietary fibre in their meals, which leads to multiple chronic conditions. Particularly vulnerable to inadequate fibre intake are children, older adults, people trying to lose weight, those on restricted grain or low gluten diets, or folks who eat out frequently.
But why is fibre so important and how can you be sure to get enough?
What is fibre?
Dietary ﬁbre is the indigestible part of plant foods that you can’t get from eating meat and dairy products.
Fibre is often talked about as one nutrient, but in reality, there are many types of dietary fibre. As all play important and diﬀerent roles in our wellbeing, it’s important to get a mix by eating a variety of unreﬁned plant foods.
Soluble: This is the fibrous component in food that gels up when it gets in contact with water. Soluble fibre helps with digestion and absorption of nutrients as well as stabilising blood sugar levels and lowering an elevated cholesterol. A major subtype is called viscous fibre.
The best sources of soluble fibre are: rolled oats, psyllium husks, legumes/lentils, barley, konnyaku, fruit and vegetables.
Insoluble: This is the roughage fibre that adds bulk to the stool and appears to help food pass more quickly through the stomach and intestines. If your bowel is a bit lazy, this type can help keep things moving.
The best sources of insoluble fibre are: wholegrain breads and cereals, intact or cracked unrefined grains e.g. bulgur wheat and brown rice, nuts and seeds, fruit and vegetables (skin and seeds).
Resistant starch: This is the non-digestible portion of starch that passes into the large bowel without being able to be broken down earlier by your digestive enzymes, which would usually occur with starches. When the ‘good’ bacteria in the large bowel ferment resistant starch, they make substances called short-chain fatty acids.
One of these—butyrate—supplies energy to the cells lining your large bowel (colonocytes), promoting their wellbeing, and strengthens the health of your gut microbiome generally.
The best sources of resistant starch are: banana (lightly ripe), cooked and cooled pasta, rice and potatoes, cooked and cooled polenta/mielimeel, legumes e.g. chickpeas, as well as products that have Hi-Maize or Barley+ added as ingredients.
How much do you need?
People with low rates of chronic disease consume at least 40 to 50 grams of ﬁbre daily. To help you work out how much you’re currently having and track your ongoing intake, consider using food diary apps such as Easy Diet Diary or My Fitness Pal. It’s important to remember that fibre is tolerated differently by each individual.
We advise you to increase your intake gradually, allowing your gut time to adjust. Speak to your dietitian if you have an existing gut condition or you require more guidance to increase your intake of the range of fibres important for wellbeing.
Remember: fibre is not just a supplement. And a low fibre diet cannot be fixed just by adding a teaspoon of fibre powder or popping a Metamucil capsule. Your entire dietary pattern must change so you are getting some fibre at each meal. The good bacteria in your gut will thank you!
6 Tips for getting enough fibre
- Include legumes in a main meal 3-4 times per week.
- Switch your breads and cereals to wholegrain varieties.
- Use the 5:1 rule. Check food labels and aim for 1 g of fibre to every 5 g of carbohydrates
- Replace white rice and reﬁned starchy foods with brown rice, wholemeal pasta, pulse pasta, barley, bulgur, polenta and other wholegrains.
- Include at least two serves of fruit and ﬁve serves of vegetables in your diet every day. Eat the skin wherever possible.
- Sprinkle nuts and/or seeds into your cereal, salads and yoghurt for a boost of fibre e.g. chia seeds, hemp seeds, ground linseeds.
Dr Sue Radd is an Advanced Accredited Practising Dietitian and one of Australia’s leading nutritionists and health communicators. Her most recent book Food as Medicine: Eating for Your Best Health received the Gourmand World Cookbook Award for Best Health and Nutrition Book in the world for 2016. Go to her website for more information.