Fibre: Why It’s So Important
What is fibre? Dietary fibre is found in vegetables, fruit, peas, beans and whole grains. You can’t digest fibre, you derive no energy from it, yet it’s a very important part of a healthy diet.
There are two types of fibre, soluble and insoluble.
Soluble fibre absorbs water and, vitally, it slows down the rate of absorption of food in the gut. Examples of soluble fibre are peas, beans, lentils, fruit and vegetables. Insoluble fibre doesn’t dissolve in water and helps to speed the passage of food through your gut. They are the tough, hard-to-chew part of grains and fruit. Other examples of insoluble fibre are: whole grains and wheat bran, beans such as kidney beans, green leafy vegetables, nuts and seeds.
Low fibre and insulin.
The fact that processed food contains low levels of fibre has a significant impact on the amount of insulin your pancreas produces.
It’s your small intestine’s job to absorb nutrients from the food you eat and send them to your liver so they can be processed into energy.
When you eat food containing fibre, the fibre forms a gel-like glutinous barrier between the food and the wall of your small intestine. This has the effect of slowing down the rate that nutrients from your food are absorbed and sent to your liver.
Consequently your liver receives a steady flow of nutrients which it processes gradually. Your pancreas is able to keep your blood glucose at the right level and to release just the right amount of insulin to store the new energy in the right place, efficiently and effectively.
When there is very little fibre in your diet.
When you eat high-calorie, energy-dense processed food which contains very little fibre, no glutinous barrier is produced to slow down the absorption of nutrients. This causes the nutrients in your small intestine to be absorbed very quickly because there is nothing to slow the process down. The result is that an avalanche of nutrients is dumped on your liver. As a result your blood glucose levels rise sharply, and your pancreas produces lots of insulin to deal with the problem.
And you thought you could trust branded food.