L10 - Macronutrients/Protein - Energy Malnutrition

Question 1

How much dietary lipid do we eat on average:

Source of dietary lipid:

Answer 1

Average UK Diet:

• 88g fat
• 40% of total energy content

Source:
TAG
Cholesterol (1g)

Question 2

Essential fatty acids:
(Give examples and function of these)

How much EFA is required? What is the average intake?

What happens if you have high intake of omega-3?

Answer 2

• These are essential: Omega-3 (linolenic) and omega-6 (linoleic)
• Needed for membrane phospholipid production and is a precursor of eicosanoids (prostaglandin, prostacyclin and thromboxane)

DoH recommend 2-5g/day. Average intake: 8-15g/day. So deficiency is very rare.

High intakes of omega-3 can (1) protect against CVD and (2) needed for the development of the brain.

Question 3

Cardiovascular Disease Facts:

Answer 3

• most common cause of death in UK
• 85,000 die every year to CVD
• cause of 40% deaths

Question 4

Risk Factors of CVD:

Answer 4

• Genetic Susceptibility
• Sedentary lifestyles
• High blood pressure
• High cholesterol
• Trans fat intake?
• T2D
• Obesity
• Smoking

Question 5

Diet and CVD:

What happens if you eat high sat fat, trans fat, and PUFA?

Answer 5

• Increased sat fat = increase cholesterol and LDL
• increased trans fat = reduce HDL
• increased PUFA = reduce cholesterol

Question 6

Types of FAs:

Answer 6

1) Saturated fats

2) Unsaturated fats: Cis (naturally occurring) and trans (not naturally occurring - only 2% of this)

Question 7

Diet and cancers:

What happens to immigrants?

Answer 7

Immigrants are more susceptible to cancers prevalent in habitant country rather than cancers present in their country of origin.

Hence, diet has more effect on cancer rather than genetics (breast, colon, pancreas and prostate).

Cancer could either be due to high fat intake of due to obesity.

Question 8

How much carbohydrate contributes to total energy content?

Source of carbohydrates:

Is it of plant or animal origin?
Is carbohydrate intake essential?

Answer 8

• 40% in developed countries
• 80-90% in poorer countries

Source of carbohydrates:

• Starch
• Sugars, esp. sucrose
• Non-starch polysaccharides (fibre)

Plant Vs. Animal Origin:
Carbs are mainly of plant origin except for lactose and glycogen.

Is Carb intake essential?
Carb intake is not essential but has protein-sparing effects (don’t need to use proteins to produce glucose).
Low carb intake = ketosis and fat utilisation

Question 9

Types of Monosaccharides in diet:

• Glucose
• Fructose
• Sorbitol
• Inositol

Answer 9

• Glucose and fructose - found in fruits
• Sorbitol - found in food made for diabetics
• Inositol - found in fibre (IP6) - alters iron and calcium absorption

Question 10

Types of Disaccharides:

• Sucrose
• Lactose

Answer 10

Sucrose:

• most commonest form
• average intake - 105g/day
• less than 60g/day is ideal - prevents dental caries
• more frequent intake rather than total amount which determines negative effects of sucrose

Lactose:

• no negative effects on health
• found in milk
• 75% are lactose intolerant

Question 11

Type of Polysaccharides:

• Starch
• NSP

Answer 11

Starch:

• Crystalline
• Insoluble
• Most commonest in our diet

NSP:

• found in fruit, veg, and cereals
• NSP rich foods - low in energy but is more bulky (feel full more quickly)
• Low amounts: Constipation, Diverticular diseases, colon cancer and appendicitis

Question 12

How much protein do we eat on average:

How much is recommended in males and females?
How much is needed in newborns?

Is protein needed in diet and what are its functions:

Answer 12

Contributes to about 10-15% of total energy in UK. In developing countries, it contributes to about 10% of total energy.

It is recommended that we eat roughly 1g/kg of body weight i.e. 55g and 44g/day for males and females.

Newborns require more protein (roughly 2g/kg/day) to allow growth.

Have EAA which are needed in diet.

Function of a.a: protein synthesis, haem, precursor for catecholamines and thyroid hormones, neurotransmitters, etc.

Question 13

Protein Quality (Animal vs. Plant origin):

Answer 13

Animal protein is of high quality - high utilisation and less waste to allow growth of animal.

Plant protein is of low quality - low utilisation and is wasted. This is also deficient in few a.a. Hence, mixing of this is needed to compensate for the deficit. This is important in poorer countries where there are vegetarians.

Question 14

UK status of protein:

What happens if you have excessive amounts of protein?

Answer 14

• No groups are deficient in protein

- Excessive protein intake: bone demineralisation and can reduce renal function in patients with renal disease

Question 15

Protein-Energy Malnutrition:

Where is this commonly seen?
What is the common diseases associated to this?

How prevalent is PEM?

Answer 15

• Common in developing countries where children tend to be deficient in energy and protein
• Leads to growth retardation: Kwashiorkor, Marasmus and Marasmic Kwashiorkor

Prevalence:

• 5 million children die from malnutrition per year
• 300 million children have growth retardation due to malnutrition
• 20-75% of children under 5 have suffered malnutrition in developing countries

Question 16

Symptom of childhood malnutrition:

Answer 16

Stunting of growth/ growth failure is common in these individuals. Have normal weight for height but low height for age.

Question 17

Classification of PEM by BMI:

Answer 17

18.5-25 = normal
17-18.5 = moderate PEM
16-17 = moderately severe PEM
≤16 = severe PEM

Question 18

Extreme forms of PEM:

What is the cause of PEM?

Answer 18

1. Kwashiorkor
2. Marasmus
3. Marasmic Kwashiorkor

This is caused by a general deficiency in food rather than a specific deficiency in a specific nutrient.

Question 19

What are the causes of childhood PEM?

Answer 19

• Poverty
• Infection
• Poor sanitation

Question 20

How is severe PEM classified in children?

Answer 20

PEM can be associated with oedema or not.

NO OEDEMA:
If expected weight for age is 60-80% - Underweight.
If expected weight for age is <60% - Marasmus.

OEDEMA:
If expected weight for age is 60-80% - Kwashiorkor.
If expected weight for age is <60% - Marasmic Kwashiorkor.

Question 21

Marasmus:

1) What type of countries does this effect?
2) Which age groups does this effect?

What causes marasmus in developing and developed countries?

Answer 21

1) Occurs in developed and developing countries
2) All age groups are susceptible to this.

Developing countries:
Caused by famine/ shortage of food.

Developing countries:
Occurs in socially and economically disadvantaged groups, individuals who have disorders in nutrient absorption and appetite, individuals with diseases (cancer, AIDS).

Question 22

Symptoms of Marasmus:

Answer 22

1) Extreme emaciation (thin)
2) Muscle wasting
3) Loss of protein from vital organs
4) Impaired immune response
5) Loss of intestinal mucosa - impairs nutrient absorption
6) Diarrhoea
7) Apathy

Question 23

Kwashiorkor:

1) Which age groups are affected?
2) What are the associated symptoms?
3) What is the cause of Kwashiorkor?

Answer 23

1) Commonly occurs in children aged 3-5 yrs old
2) Severe oedema (pitting, painless), enlarged liver and fat infiltration, dermatitis, changes in colour and texture of hair. If severe, it can lead to permanent mental retardation.
3) General food deficiency = lack of antioxidants. More susceptible to infections which increases protein requirements. Demands exceeds supply leading to Kwashiorkor. Infection precipitates kwashiorkor.

Question 24

What is Marasmic Kwashiorkor?

Answer 24

Where both conditions are present. Can have both conditions in one family.

Child can switch between the two conditions.

Question 25

How do you treat PEM:

Answer 25

1) First, electrolyte and fluid has to be balanced.
2) ORS (Oral rehydration solution)*** - 8 tsp sugar, 1 tsp salt, 1 litre of boiled water.
3) Dextrose solution
4) Dilute milk
5) Can give food when tolerated