Macronutrients

Question 1

What are the three main macronutrients?

Answer 1

Protein
Fat
Carbohydrate

Question 2

What is a nutrient?

Answer 2

A chemical substance, found in food and needed by the body.

Question 3

What are the functions of protein?

Answer 3

1. STRUCTURE of muscle, skin and hair.
2. GROWTH, especially during pregnancy, childhood and adolescence.
3. REPAIR damaged body tissues or recovery after illnesses.
4. Produce ENZYMES for digestion.
5. Produce HORMONES that regulate body functions eg. testosterone and estrogen
6. Provide a secondary source of ENERGY
   - 1g of protein provides 4kcal of energy.

Question 4

What are the animal sources of protein?

Answer 4

meat, fish, eggs and dairy products

Question 5

What are the plant sources of protein?

Answer 5

pulses, grains, beans and nuts

Question 6

What are the novel protein sources?

Answer 6

tofu, soya, tempeh

Question 7

What is the difference between plant and animal sources of protein?

Answer 7

Animal sources have a higher biological value than proteins from plant sources.

Question 8

What are proteins made up of?

Answer 8

Amino acids

Question 9

What is the difference between dispensable and indispensable amino acids?

Answer 9

Dispensable amino acids are produced in the body whereas indispensable amino acids cannot be produced in the body and must be provided by the diet.

Question 10

How many amino acids do humans need?

Answer 10

20

8 of which are indispensable

Question 11

What is a Low Biological Value (LBV) food?

Answer 11

A food that lacks one or more of the indispensable amino acids.

Question 12

What is a High Biological Value (HBV) food?

Answer 12

A food that contains all the indispensable amino acids.

Question 13

What is protein complementation?

Answer 13

When two LBV foods are eaten together in the one meal to provide all the indispensable amino acids.

Question 14

What are the functions of fat?

Answer 14

1. Source of ENERGY
2. INSULATES the body to stop it losing heat
3. PROTECTS organs and bones against damage
4. Forms the structure of body CELLS
5. Source of fat soluble VITAMINS A and D
6. Source of the essential fatty acids OMEGA 3 and OMEGA 6

Question 15

What are the characteristics of saturated fats eg. butter?

Answer 15

> Solid at room temperature
Animal source
A diet high in saturated fat can lead to raised blood-cholesterol levels, which can lead to cardiovascular disease (CVD)

Question 16

What are the characteristics of unsaturated fats eg. olive oil or sunflower oil?

Answer 16

> Liquid at room temperature
Plant sources
Better for health
There are TWO types

Question 17

What are the two types of unsaturated fats?

Answer 17

> MONUNSATURATED fats
- one unsaturated double bond in the molecule

> POLYUNSATURATED fats
- more than one double bond in the molecule

Question 18

What are the sources of saturated fats?

Answer 18

meat, eggs, dairy products and butter

Question 19

What are the sources of unsaturated fats (monounsaturated and polyunsaturated)?

Answer 19

MONUNSATURATED- vegetable oils, nuts and avocados

POLYUNSATURATED- oily fish, meat and seeds

Question 20

What is the function and sources of Omega 3 fatty acids?

Answer 20

Prevent blood clotting which protects the heart and can reduce risk of cardiovascular disease (CVD)

Oily fish- mackerel

Question 21

What is the function and source of Omega 6 fatty acids?

Answer 21

Positive impact on blood cholesterol which can reduce the risk of cardiovascular disease (CVD)

Vegetable oils

Question 22

What is the function of carbohydrates?

Answer 22

1. Provides the body with ENERGY (1g provides 3.75kcal of energy)
2. Has a PROTEIN-SPARING effect, so that protein is used for growth and repair rather than for energy
3. Provides FIBRE that aids in digestion and prevents bowel disorders

Question 23

What are the sources of carbohydrates?

Answer 23

Sugary carbohydrates: cakes, biscuits, honey and fruit juice

Starchy carbohydrates: grains, cereals, pasta, and rice

Question 24

What is the difference between sugary carbohydrates and starchy carbohydrates?

Answer 24

Sugars absorb quickly and raise blood sugar levels rapidly.

Starches take longer to digest and absorb; they are complex carbohydrates. They help keep the blood sugar levels constant and are also a great source of fibre which aids in healthy digestion and prevents against bowel cancer.