Dietary Requirements

Question 1

What elements of food intake and lifestyle have been linked to cancer?

Answer 1

Excess energy rich foods (fat and sugar), physical inactivity, carcinogens, nitrates used in preservation, accidental contaminants (moulds producing aflatoxin and fungi).

Question 2

Foods with high sugar and fat content predispose us to?

Answer 2

Dental caries and obesity

Question 3

In the UK, dietary reference values for food energy and nutrients are stated as?

Answer 3

Reference Nutrient Intakes

Question 4

Reference Nutrient Intakes provide sufficient intake standards to meet the demands of what % of the population?

Answer 4

97.5%

Question 5

Most individuals intakes are below the RNI therefore what other value is presented which represents the amount adequate for most?

Answer 5

Estimated Average Intake EAR

Question 6

The Lower Reference Nutrient intake fails to meet the requirements of what % of the population?

Answer 6

97.5%

Question 7

What is the SI measurement of energy?

Answer 7

joule

Question 8

How many kilocalories are in 1kilojoule?

Answer 8

0.239kcal

Question 9

What is the conversion factor of kj to kcal?

Answer 9

4.2kj per 1kcal

Question 10

What are the two approaches in assessing energy requirements for weight-stable subjects close to their energy balance?

Answer 10

1. Assessment of their energy intake

2. Assessment of their total energy expenditure

Question 11

Total energy expenditure is the sum of?

Answer 11

TEE = Basal metabolic rate (BMR) x [Time in bed + (Time at work x PAR) + (Non-occupational time x PAR)]

Question 12

Total energy expenditure can be measured using?

Answer 12

Double-labelled water technique

Question 13

What is involved in the double-labelled water technique?

Answer 13

Water containing stable isotopes 2H and 18O is given orally. As energy is expended, Co2 and H20 are produced. The difference between the rates of loss of the two isotopes is used to calculate Co2 production which is then used to calculate energy expenditure.

Question 14

How is BMR calculated?

Answer 14

You can measure oxygen consumption and CO2 production but usually its taken from standardised tables of age, weight and sex.

Question 15

One mol of glucose produces how many mol of ATP?

Answer 15

36 mole of ATP

Question 16

In the UK the estimated average daily energy requirements for 55 year old male and female would be?

Answer 16

Male - 2550kcal (10600kj)

Female - 1940kcal (8100kj)

Question 17

In the UK the current diet comprises what % of each macronutrient?

Answer 17

50% carbohydrate, 35% fat, 15% protein and 5% alcohol

Question 18

In what instances would energy requirements increase?

Answer 18

Pregnancy, lactation, trauma, infection

Question 19

In general the increased BMR associated with inflammation or trauma is counteracted or more than counteracted by a decrease in?

Answer 19

Physical activity so requirements are not increased

Question 20

In the basal state what are the % energy demands for resting muscle, abdominal viscera, brain and the heart?

Answer 20

Resting muscle 20%, abdominal viscera 35-40%, brain 20% and heart 10%

Question 21

Virtually all body fat and glycogen is available for oxidation but how much protein is?

Answer 21

<50%

Question 22

Which macronutrient accounts for the largest reserves in energy for lean and obese subjects?

Answer 22

Fat stores

Question 23

A gain or loss of how much energy would increase or decrease body weight by 1kg?

Answer 23

25-29MJ / 6000-7000kcal

Question 24

In the UK what is the adult daily RNI for protein?

Answer 24

0.75g/kg

Question 25

Most affluent individuals consume around how much protein per day in grams?

Answer 25

80-100g

Question 26

The balance between protein breakdown and synthesis is measured by?

Answer 26

The total amount of nitrogen excreted in urine

Question 27

In order to maintain nitrogen balance, how much protein is needed in grams?

Answer 27

40-50g of dietary protein

Question 28

The amount of protein oxidised can be calculated from?

Answer 28

The amount of nitrogen excreted in the urine over 24 hours using the equation: Gram of protein required = urinary nitrogen x 6.25 (most proteins contain around 16% of nitrogen)

Question 29

Urinary urea is more easily measured in practice and forms what % of the total urinary nitrogen?

Answer 29

80-90%

Question 30

In healthy individuals what does urinary nitrogen excretion reflect?

Answer 30

Protein intake

Question 31

In what conditions does urinary nitrogen not reflect protein intake?

Answer 31

Catabolic (negative N balance) or during growth or repletion following an illness (positive N balance)

Question 32

What are the 9 essential amino acids?

Answer 32

Phenylalanine, valine, tryptophan, threonine, isoleucine, methionine, histidine, leucine, lysine

Question 33

How can you increase your amino acid intake on a vegan diet?

Answer 33

Combine foodstuffs e.g. maize (cereals) and legumes

Question 34

Inadequate protein and inadequate energy intake can lead to?

Answer 34

Loss of protein from the body (negative nitrogen balance)

Question 35

What happens to protein when there is a loss of energy from the body?

Answer 35

More protein is directed towards oxidative pathways and eventually gluconeogenesis for energy

Question 36

What is the role of the amino acid Glutamine?

Answer 36

The most significant amino acid in the circulation and in inter-organ exchange

Question 37

What is the role of the amino acid Alanine?

Answer 37

It is released from muscle, deaminated and converted into pyruvic acid before entering the krebs cycle

Question 38

What is the role of the amino acid homocysteine?

Answer 38

It is a sulphur containing amino acid derived from methionine in the diet. A raised plasma concentration of homocysteine is an independent risk factor for vascular disease

Question 39

Which amino acid is required for haem production?

Answer 39

Glycine

Question 40

Which amino acid is required for melanin and thyroid hormones?

Answer 40

Tyrosine

Question 41

Which amino acids are required for nucleic acid bases?

Answer 41

Glutamine, Aspartate and Glycine

Question 42

Glutamate, cysteine and glycine are amino acids required for glutathione. What is glutathione?

Answer 42

Part of the defence system against free radicals

Question 43

What is dietary fat in the form of?

Answer 43

Triglycerides

Question 44

What are triglycerides?

Answer 44

Esters of glycerol and free fatty acids

Question 45

What do fatty acids vary in?

Answer 45

Chain length and saturation

Question 46

Hydrogen molecules in fatty acids related to double bonds (cis or trans) are mostly in which form in foods?

Answer 46

Cis

Question 47

What are the two essential fatty acids?

Answer 47

Linoleic and alpha-linoleic

Question 48

Alpha-linoleic and linoleic acids are precursors for what?

Answer 48

Prostaglandins

Question 49

What two acids can linoleic and linolenic acid make?

Answer 49

Eicosapentanoic (EPA) and docosahexanoic (DHA)

Question 50

Dietary fat provides how many kj/kcal per gram?

Answer 50

37kj / 9kcal

Question 51

What is the main source saturated fat is derived from?

Answer 51

Animals

Question 52

What is the main source omega-6 fatty acids are derived from?

Answer 52

Vegetable oils and other plant foods

Question 53

What is the main source omega-3 fatty acids are derived from?

Answer 53

Vegetable foods, rapeseed oil, fish oils

Question 54

What is the main source trans fatty acids are derived from?

Answer 54

Hydrogenated fat or oils e.g. margarine, cakes and biscuits

Question 55

What impact do trans fatty acids have on the body which is similar to saturated fatty acids?

Answer 55

Increase circulating LDL and decrease HDL which raise the risk of CVD

Question 56

N-6 polyunsaturated fatty acids are components of?

Answer 56

Membrane phospholipids, influence membrane fluidity and ion transport. They also have antiarrhythmic, antithrombotic and anti-inflammatory properties which prevent CVD.

Question 57

What is the role of N-3 fatty acids in the body?

Answer 57

Increase circulating HDL cholesterol and lower triglycerides which may reduce CVD.

Question 58

What do the British Nutrition Foundation and the American Heart Association recommend regarding the intake of n-3?

Answer 58

Two-fold increase in N-3 | 3 PUFAs by eating more fish or ingesting fish oil capsules

Question 59

What products is cholesterol found in?

Answer 59

All animal products

Question 60

What is the average daily cholesterol intake in the UK?

Answer 60

300-500mg

Question 61

What can affect blood cholesterol levels?

Answer 61

Either very high or very low cholesterol diets

Question 62

Which patients are at risk of essential fatty acid deficiency?

Answer 62

Patients on long-term parenteral nutrition given glucose, protein and no fat

Question 63

What is the recommended dietary fat intake including total fat, sat fat, cis mono and cis poly?

Answer 63

Total fat - 15-30%, Sat fat <10%, Cis monounsaturated 20%, Cis polyunsaturated 6%

Question 64

What is the recommended healthy dietary intake of cholesterol in mg/day?

Answer 64

<300

Question 65

What is the recommended healthy dietary intake of salt per day?

Answer 65

<6g

Question 66

What is the recommended total dietary fibre intake per day?

Answer 66

30g >25g/day

Question 67

How many kilojoules/kcal in one gram of carbohydrate?

Answer 67

17kj / 3.75kcal

Question 68

Carbohydrate intake comprises?

Answer 68

Polysaccharide starch, disaccharides (mainly sucrose), monosacharides (glucose and fructose)

Question 69

The WHO suggests sugar intake should be how much of a persons intake?

Answer 69

<5%

Question 70

Dietary fibre is largely in what form?

Answer 70

Non-starch polysaccharides

Question 71

Dietary fibre is often removed when?

Answer 71

In the processing of food

Question 72

When dietary fibre is removed during processing food what is left?

Answer 72

Highly refined carbohydrates such as sucrose which contributes to dental caries and obesity

Question 73

What is lignin?

Answer 73

Its included in dietary fibre in some classification systems but is not a polysaccharide just a minor component of the diet

Question 74

What are the principle classes of Non-starch polysaccharides?

Answer 74

Cellulose, hemicelluloses, pectins, gums

Question 75

Cellulose, hemicelluloses, pectins and gums are not digested by gut enzymes however NSP is partly broken down in the GI tract by colonic bacteria producing what?

Answer 75

Gas and volatile fatty acids e.g. butyrate

Question 76

Bran is the fibre from which NSP?

Answer 76

Wheat

Question 77

What effect does consuming bran have on health?

Answer 77

Increase faecal bulk and helpful in the treatment of constipation

Question 78

What is our average daily intake of NSPs?

Answer 78

16g

Question 79

What should we increase in our diet to reach 30g/d fibre?

Answer 79

Potatoes, bread, fruit and veg

Question 80

Each gram of daily fibre contributes which weight of stool?

Answer 80

3-5g

Question 81

Which NSPs are added to food to slow down monosaccharide absorption and is beneficial for those with Type 2 Diabetes?

Answer 81

Pectins and gums

Question 82

A diet high in plant foods has been linked to protection against ischaemic heart disease, stroke and certain cancers by what mechanism?

Answer 82

It has a lipid-lowering effect and contains protective substances such as vitamin and non-vitamin antioxidants and other vitamins such as folic acid which is linked to homocysteine metabolism which is a risk factor for CVD.

Question 83

Fermentation of fibre in the colon may protect you against?

Answer 83

Colon cancer

Question 84

In the UK milk and margarine are fortified with which vitamins?

Answer 84

A and D

Question 85

In the UK flour is fortified with which 4 things?

Answer 85

Calcium, iron, thiamine and niacin

Question 86

What are cereals fortified with?

Answer 86

Several vitamins and iron

Question 87

What is Olestra and what has it been used for?

Answer 87

A polymer of sucrose and 6/+ triglycerides and used to combat obesity in snack foods because it is not absorbable so reduces total calorie intake

Question 88

What are some side effects of Olestra?

Answer 88

Loose stools and abdominal cramps

Question 89

Define Nutrient Goals?

Answer 89

National intakes of nutrients that are considered appropriate for optimal health in the population. Based on scientific information linking nutrient intake to disease

Question 90

Define Dietary Guidelines?

Answer 90

Refer to the dietary methods used to achieve the nutrient goals

Question 91

What are the nutritional consequences of underlying disease?

Answer 91

Anorexia, increased nutrient requirement

Question 92

What are the nutritional consequences of muscle weakness (respiratory and peripheral muscle) or severe arthritis in hands and arms?

Answer 92

Problems with shopping, cooking and eating

Question 93

What are the nutritional consequences of swallowing problems, GIT and painful obstructions of the mouth?

Answer 93

Inadequate food intake and risk of aspiration or pneumonia

Question 94

What are the nutritional consequences of GIT symptoms including nausea, vomiting, diarrhoea and jaundice?

Answer 94

Food aversion, malabsorption (small bowel disease), anorexia

Question 95

What are the nutritional consequences in those with a sensory deficit (impaired sight, hearing etc)

Answer 95

Difficulties in shopping, cooking and decreased food intake

Question 96

What are the nutritional consequences of loneliness, depression, bereavement, confusion, living alone, alcoholism and drug addiction?

Answer 96

Self-neglect, inadequate intake of food or poor quality of food

Question 97

What are the nutritional consequences of polypharmacy'?

Answer 97

Confusion, sedation, depression and GIT side effects including malabsorption of some nutrients