Fibre

Question 1

Typical recommendations for fibre

Answer 1

30g fibre per day

Question 2

Why might people need a low fibre or low residue diet?

Answer 2

Medical conditions to protect the bowel

Question 3

Low residue diet

Answer 3

Diet with very little or no fibre (or roughage)

Question 4

Purpose of low fibre diet

Answer 4

Reduce poorly or partially digested foods including foods that leave behind a roughage post digestion as this can lead to blockages in the bowl and other unwanted digestive symptoms

Question 5

Diet may reduce …

Answer 5

Number of bowel movements
Stool size
Risk of bowel blockages
Irritation in an inflamed bowel
Abdominal pain and diarrhoea

Question 6

Conditions where a low fibre diet may be appropriate…

Answer 6

Inflammatory bowel disease
High output stoma
Bowel blockages
Result of pelvic or abdominal radiotherapy
Prepare bowel prior to surgery
Rest the bowel after surgery

Question 7

Residue

Answer 7

Undigested food that reaches your bowel

Question 8

Residue is predominant fibre but includes food like…

Answer 8

Charred foods
Some fats
Foods containing resistant starch

Question 9

Typically a low residue diet would have between … and … g of fibre per day

Answer 9

7-15 g per day

Question 10

Low residue diets are typically required for a … period of time

Answer 10

Short

Question 11

If diet is required in long term patients are advised to take a …

Answer 11

Multi-vitamin

Question 12

Dietary guidance for a low residue diet…

Answer 12

Reduce high fibre foods and swap for low fibre alternatives
5 fruit and vegetables per day but low fibre options
Regular meals and snacks
Wide variety of foods everyday
Chew well before swallowing
8 glasses of fluid per day
May require multivitamin supplement

Question 13

Dietary fibre

Answer 13

Carbohydrates found naturally in plants
Unlike other carbohydrates, it cannot be digested in the small intestine so reaches the large intestine intact

Question 14

Fibre containing foods keep our … system healthy and prevent …

Answer 14

Digestive and constipation

Question 15

Fibre may reduce risk of some diseases…

Answer 15

Cardiovascular disease
Type 2 diabetes
Obesity
Cancers e.g. bowel cancer

Question 16

Fibre recommendation per day for 2-5 years

Answer 16

15 g

Question 17

Fibre recommendation per day for 5-11 years

Answer 17

20 g

Question 18

Fibre recommendation per day for 11-16 years

Answer 18

25 g

Question 19

Fibre recommendation per day for 17+ years

Answer 19

30 g

Question 20

Source of fibre

Answer 20

3 g per 100 g

Question 21

High in fibre

Answer 21

6 g per 100 g

Question 22

Fibre is completely or partially broken down by … in your …

Answer 22

Bacteria and large intestine

Question 23

Fibre includes … and …

Answer 23

Polysaccharides and resistant oligosacchardies

Question 24

Soluble fibre

Answer 24

Pectins and beta glucans found in fruits and oats

Question 25

Insoluble fibre

Answer 25

Cellulose found in wheat bran and nuts

Question 26

Resistant starch

Answer 26

Soluble fibre that is highly fermentable in gut Broken down to produce SCFAs

Question 27

Prebiotics

Answer 27

Type of carbohydrate only gut bacteria can feed upon E.g. onions, garlic and bananas

Question 28

Eating a range of dietary fibre can…

Answer 28

Improve diversity of microbiota Improve constipation and lactose intolerance Enhance immunity Reduce inflammation in gut

Question 29

Englyst method to measure dietary fibre

Answer 29

Dietary fibre is measured specifically as non-starch polysaccharides (NSPs) Starch is removed with the use of enzymes then the remaining NSPs are precipitated with ethanol These are then broken down into sugars by acid hydrolysis The sugars left are then quantified using chromatography to determine the total, soluble and insoluble amounts of NSPs

Question 30

Southgate method to measure dietary fibre

Answer 30

Dietary fibre is measured by removing soluble sugars, fats and starch from a sample After this, the remaining product undergoes chemical hydrolysis and extraction This calculates the total fibre by adding lignin and polysaccharides that are not digested by enzymes

Question 31

AOAC method to measure dietary fibre

Answer 31

Dietary fibre is measured by human digestion being simulated by samples being digested with enzymes such as a-amylase and protease at 37 degrees Celsius This removes starch and protein After this, the product is precipitated with ethanol to form insoluble and soluble fibres These are filtered, dried and weighed to obtain the fibre content

Question 32

Fibre recommendations change in 2015

Answer 32

SACN incensed recommended daily value from 24g to 30g for adults

Question 33

Lignins

Answer 33

Complex organic polymers found in xylem in cell wall of plants Provide strength to cell wall, protect from decay and allow for water transport Hydrophobic - allows efficient water transport Complex structure - hard for microorganisms to breakdown