Our Palaeolithic ancestors consumed around 100 grams of fibre per day compared to about 15 grams per day on a modern diet.
Take into account that their fibre was not from cereals as it is now. Instead, all their fibre came from wild fruits and vegetables, nuts, herbs, shoots and roots.
The amount of fibre you eat determines how many bacteria live in your gut, and the type of bacteria determines which species of bacteria flourish.
The average adult has around 2kg of bacteria in their body. These bacteria are essential for good health. Most are located in the digestive tract, particularly in the lower (large) intestine and they feed on the indigestible fibre in our food.
A by-product of this bacterial digestion of fibre is the production of short chain fatty acids such as butyrate. These short-chain fatty acids have numerous healthy benefits:
• They are the most important source of energy for your body, more important than glucose from carbohydrates. This means that having sufficient fibre in your diet and healthy gut bacteria is essential for good health and a high level of energy and brainpower.
• They bind to a receptor on immune cells, reducing inflammation.
• They assist with tissue healing and repair.
• They prevent obesity by improving insulin sensitivity.
• They lower blood insulin, triglyceride and cholesterol levels, reducing the risks of heart disease, diabetes and other diseases.
Fibre in excess.
Like anything in life too much of a good thing has its side effects and fibre is no different.
Large quantities of fibre, especially grains, seeds and legumes may be harmful. This type of fibre contains excessive roughage that can injure the intestinal wall, and toxins from these foods cause inflammation of the gut in addition to the other problems caused by grains and legumes.
The heart foundation recommends that’s adults should consume approximately 25-30g daily.
Children aged between four and eight should consume 18g of fibre each day.
Some excellent fibrous food sources include:
•Bok choy and other Asian greens