Design and Technology/Biology KS3: The science behind dietary fibre

Radio 1Xtra DJ Twin B explains how his breakfast rich in fibre gives him the energy for his show. Meanwhile, Stefan Gates uses a chemical replica of your gut to show how fibre creates gas.

The importance of soluble and insoluble dietary fibre in the diet, rich food sources, and its function in the body are discussed.

The difference between soluble and insoluble fibre is explained, and the way each of these relates to the speed of movement through the digestive tract to prevent constipation and diarrhoea.

An experiment shows the gas produced by bacteria in the colon.

This short film is from the BBC series, Gastro Lab.

Teacher Notes

You could task your students with evaluating their daily food intake for fibre content.

Take your favourite snack. How much fibre do you think it contains? How many plant based foods are in the recipe? Look up which foods are high in fibre and see if you can adapt your recipe to increase the fibre content.

Students can be asked to make a display to show the dietary fibre content per portion of a selection of foods (for example, breakfast cereal, porridge oats, apple, nuts, lentils, biscuits).

How could you increase the amount of fibre that you can eat each day?

Curriculum Notes

This short film is relevant for teaching biology and food technology at Key Stage 3 in England, Wales and Northern Ireland, and 3rd Level in Scotland

More from Gastro Lab:

The science behind carbohydrates
The science behind fat
The science behind hydration
The science behind protein
The science behind vitamins and minerals