56. Physiological basis of nutrition, essential nutrients

Question 1

What is rational nutrition

Answer 1

The supply of foods adequate to the energetic and synthetic needs of the body
That secure a good health, welfare and physical performance of the individual and future generations

Question 2

what does an optimal diet include

Answer 2

intake of calories, proteins, lipids, carbohydrates, water, minerals, microelements, vitamins

Question 3

What is the energy liberated from the complete oxidative breakdown of 1g carb to carbon dioxide and water

Answer 3

4.1 kcal (17.15 kJ)

Question 4

What is the energy liberated from the complete oxidative breakdown of 1g of fats

Answer 4

9.3 kcal ( 38.91 kJ)

Question 5

What is the energy liberated from the complete oxidative breakdown of proteins to carbon dioxide, urea and water

Answer 5

4.35 kcal 1(8.20 kJ)

Question 6

Since the absorbtion of the substances vary in gastointestinal tract, what is the avergae physiologically available energy per gram

Answer 6

Carb:fats:proteins

4:9:4

Question 7

What are the major principles of rational nutrition

Answer 7

1. Energy intake with food should correspond to the energy requirements of the body
2. It is based on the principle of proper nutrient balance

3.The daily menu should provide the required amounts of vitamins, water, minerals, microelements, fibres

4. Rational nutrition presumes a proper daily plan of food intake distribution - number of meals, mealtimes etc

Question 8

Principles of rational nutrition: 1

Answer 8

It should be enough to maintain basal metabolism and physical activity

Including increased energy needs for growth, prgenancy, lactation, bod building

Its different for diff genders, age and level of physical activity

Question 9

Principles of rational nutrition: 2

Answer 9

Food should contain basic nutrients= P:F:CHO

Ratio of P:F:CHO= 1:1:4

CHO increased to 5/6 in intensive physical activity

Question 10

How much protien should be from animal origin

Answer 10

40-60%

Question 11

How much fats should be from plant oriign

Answer 11

33%

Question 12

Principles of rational nutrition: 3

Answer 12

ceratin vitamisn and microelements have upper limits - hypervitaminosis id exceeded

Vit A= 5000 IU
Vit D=400 IU
thiamine=1.5 mg
riboflavin=1.8 mg
niacin=20 mg
Ascorbic acid = 45 mg
Vit k 70 mg

Question 13

Principles of rational nutrition: 4

Answer 13

Need variety of foods from all 7 basic food groups

Take into account amount of food (satietyand fiber), quality of food ( health) cooking (depends on family)

Question 14

Where are protiens broken down and what into

Answer 14

broken down in the lumen of the digestive tract
Into amino acids

Question 15

What do cells use proteins for

Answer 15

synthesis of enzymes,transport protiens, hormones, cell membranes, antigens, antobodies

Question 16

What is the average half life of body proteins in the body

Answer 16

Half life= rate of synthesis and degradtion of proteins

average = 80 days

Question 17

The essential amino acids are those that need to be taken up via diet. What are they

Answer 17

histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, and valine

Question 18

What are first class proteins and second class proteins

Answer 18

first= proteins of animal origin and contain all essential amino acids

second= proteins of plant origin, dont contain all essential amino acids

Question 19

What is the required protein intake of adults

Answer 19

protein of animal origin: 0.75g/kg

protein of mixed origin; 0.9g/kg

if protien intake is low in essential amino acids,the amount of protein eaten is larger

Question 20

Does protein demands decrease with age?

Answer 20

no
]although energy requirements decrease, protein requirement does not

Question 21

Who may have a greater demand for protein in food

Answer 21

adolescents
during disease and injury
heavy physical workers and athletes

Question 22

In additioon to enery, what other properties does carbs have

Answer 22

structure forming-glycosaminoglycans are part of intracellular matrix

cell membrane composition- glycoproteins

Question 22

What is the main energy source for our body

Answer 22

Carbohydrates

Question 23

What are the classes of carbs in food

Answer 23

simple= glucose, fructose, gaalctose, lactose maltose

complex= starch, cellulose, glycogen, pectin

Question 24

What is the main difference btw simple and complex carbohydrates

Answer 24

simple sugars are assimilated more rapidly and cause an abrupt rise in concentration of glucose therefore increased insulin in blood

Question 25

the digestible carbohydrates are broken down in the lumen of the digestive tract into monosaccharides
which carbohydrates are not

Answer 25

cellulose and hemicellulose

Question 26

What % should carbohydrates be part of the body daily energy requirement

Answer 26

55-63%

Question 27

Why should a minimum amount of carbohydrate be present in diet

Answer 27

brain cells use only glucose as enery source

Question 28

Why are carbs known as protein sparing compounds

Answer 28

Excess carbs stored as fat reserves

Question 29

Foods richest in carbohydrates

Answer 29

grains, fruits, veg

Carb content LOWER in animal orgin= milk, glyogen from meat

Question 30

What are fibers

Answer 30

indigestible plant polysacchrides and other types of iopolymers

they pass along the small intestine and absorb water, toxic/carcinogenic substances, heavy metals,

Question 31

What are the main dietary fibers

Answer 31

cellulose, hemicellulose, pectins, gus,lignins

Question 32

What is the beneficial effects of fibers

Answer 32

their ability to increase the volume and rate of intestinal contents passage

reduces the stay of fecal masses in colon

Question 33

Amount of fiber needed by an adult

Answer 33

16-24g/day

main sources are cereal seeds, root veg,cauliflower, broccoli legumes

Question 34

What does dietary fats consist of

Answer 34

triglycerols, cholesteral, holesterol esters, phospholipuids, liid soluble votamisn

Question 35

As well as energy what else is lipids used for

Answer 35

cell membranes, synthesis of hormones, bile salts, vit D

Question 36

How are fats classified

Answer 36

unsaturated= double bonds (veg fats)
Saturated= no double bonds (animal fats)

Question 37

What are essential fatty acids

Answer 37

Important for normal growth of children and animals

They are polyunsaturated fats- omega-3 fatty acids and omega-6 fatty acids

Not synthesied by body cells

Question 38

What is the main omega-3 fatty acid

Answer 38

a-linolenic acid

Eicosapentaenoic acid and docosahexaenoic acid are synthesied from this

The latter imp for development of brain-phospholipds in brain, synatic transmission

Also precursors of eicosanoids-functional regulators

Question 39

Fats daily energy intake

Answer 39

25-30%

saturated= less than 10%
polyunsaturted=3-7%- potential source of free radicals
cholesterol=less than 300mg

Question 40

Where is cholesterol found

Answer 40

ONLY in animal products=egg yolk, butter, meat

Question 41

What fats are high in essential fatty acids

Answer 41

fish oil and veg fat