Nutrition: it is the dynamic processes by which the body can utilize the consumed food for energy production, growth, tissue maintenance and regulation of body functions.

1. Dr. Dalia El-Shafei
Assoc. prof., Community Medicine Department, Zagazig
University

2. LEARNING OBJECTIVES:
Identify sources, functions, effect of deficiency of nutrients.
Understand the characteristics of adequate, balanced diet.
Develop a diet plan by using the dietary guides and nutritional pyramid.
Describe diets for vulnerable groups.
Understand the causes, manifestations and control of malnutrition problems.
Explain methods of assessment of nutritional status.
Describe diet plans for selected chronic diseases (therapeutic diet).

4. Nutrition
• The dynamic processes by which the body can utilize the consumed food for energy
production, growth, tissue maintenance and regulation of body functions.
A nutrient
• A chemical substance that is present in food & needed by the body in amounts of g. as
macronutrients (carbohydrates, proteins, fats) or mg. or µg. as micronutrients
(vitamins, minerals) for energy production, growth and regulation of body functions.
Food
• Anything liquid or solid formed of different nutrients & utilized by the body for
energy production, growth, tissue maintenance, and regulation of body functions.
Diet
• The whole daily consumed food.
A
kilocalorie
• The unit of measure used to express the fuel value produced from food. It equals
the amount of heat needed to raise the temperature of 1 liter of water 1°C.

5. Safe food
• The food which is free of artificial or natural harmful
compounds, not contaminated with infectious agents or
toxins or heavy metals and not polluted by radiation.
Food security
• The availability of food in adequate quantity & quality
with reasonable price at any time for all groups of
population.
Food
supplementation
• Providing of food of a high nutritive value to vulnerable
groups at low prices or free of charge e.g., milk powder
for infants, flour, cheese & cereals for pregnant &
lactating mothers.
Food fortification
• Addition of a certain nutrient to a particular food in which
it is deficient to improve its nutritive value, e.g, addition
of I2 to table salt, iron to flour, vitamins A & D & E to
vegetable oils & powdered milk.
Food enrichment
• Addition of certain nutrients to food which lost during
food baking or processing as addition of vit.B to flour &
vit.C to milk.

8. FOOD CONSTITUENTS:
Macronutrients:
Nutrients which
are needed in
grams as:
carbohydrates,
proteins and fats.
Micronutrients:
which are needed
in milligrams or
micrograms as
vitamins,
minerals and
trace elements.
Water: it forms
about 70% of
body weight.

10. CARBOHYDRATES
Formed for C-H-
O atoms.
Carbon atom is
the source of
energy.
They are mainly
found in plant
foods (made by
photosynthesis).
Only animal food
containing crab.
is milk “source of
sugar (lactose)
for babies before
they be able to
eat solid food”
About 50-55% of
daily energy
requirements
“recommended
by the guidelines
for healthy diet”.

11. FUNCTIONS OF CARBOHYDRATES:
Provide
energy: 1
gram → 4
kcals.
Spare
protein from
burning for
energy
production.
Aid in more
efficient &
complete
oxidation of
fats for
energy
production.
Dietary
fibers

12. Functions of soluble fibers (as
white apple, pectins, beans….etc)
• ↓ total serum cholesterol level because
they absorb bile salts in intestine, so
liver consumes more amount of
cholesterol to form more bile salts.
• Help promote normal blood glucose
level (delay digestion).
• Enhance body use of insulin in insulin
resistance syndrome as all types of fibers
contribute to low glycaemic index meals.
Functions of insoluble fibers (as
apple skin, cellulose….etc)
• Absorb water 10-15 times their
volume, so add bulk to food.
• Satiating action.
• Stimulate intestinal motility, so
prevent constipation→ ↓colonic
pressure & ↓ absorption of toxins and
carcinogens from colon.

13. DISORDERS OF EXCESS CARBOHYDRATE INTAKE:
(EXCESS SUGAR INTAKE)
Obesity (with
its
complications).
Dental caries
(sucrose is
cariogenic).
↑ Insulin output
• ↑Blood
triglycerides→↑fat
deposition &
atherosclerosis
• ↑ tendency for blood
clotting.
• More rapid return to
hunger pains after a big
meal.

14. LIPIDS
All fats are lipids but not all lipids are fats

15. FATS:
Formed of C-H-O atoms with greater
concentration of carbon → more energy
values “1gm →9 kcals”.
Fats in our bodies (in adipose tissue) 95%
are triglycerides which are formed of 3 fatty
acids + 1 molecule glycerol (water-soluble
carbohydrate) which allows the transport of
fats through the water-based blood stream.

17. FATTY ACIDS: ARE CLASSIFIED INTO
Saturated F.A. (SFA): hard in
room temp., mainly animal fats,
coconut oil, palm oil.
Unsaturated F.A. (USFA):
liquid in room temp., mainly
vegetable oils (olive oil, corn
oil, sunflower oil & cotton seed
oil).
Essential F.A.: cannot be
synthesized in the body as:
Linoleic, Linolenic &
arachidonic acids.
Non-essential F.A.: can be
synthesized by the body.

18. FUNCTIONS
OF
FATS: • The most concentrated source of energy: 1gm →9 kcals.
• Sparing burning of protein if carbohydrate deficient.
• Sources of essential fatty acids.
• Give satiety & add flavor and palatability to food.
• Promote absorption of fat-soluble vitamins.
• Insulate & control body temperature.
• Protect body organ by cushioning.
• Provide some structural components as cell membranes, axon sheath of nerve
cells and some digestive hormones and enzymes.
• Omeg-3 fatty acids: unsaturated F.A. (EPA-DHA) found in fish oils (sardines,
salmon and mackerel) and have the following functions:
• ↓arterial stiffness. -↓clotting time of blood.
• ↓ risk of cancer. - ↓inflammation process. -↑level of H.D.L.
• Functions of olive oil: (monounsaturated F.A.):
• Improve insulin resistance syndrome status. -Elevate HDL level.

19. Fats in cold water fish are mainly Omega-3 F.A. which do not
solidify in the very cold arctic water. Imagine that would happen to
these fish if their body fat consisted of saturated fat, they would
solidify and sink. Therefore, fish from cold arctic waters have to be
high in Omega-3 F.A. to survive

20. TYPES OF CHOLESTEROL:
HDL cholesterol has more protein
than LDL or VLDL which allows
more cholesterol to be taken from
the body cells resulting in removal
of cholesterol through the liver.
High density
lipoprotein
cholesterol
(HDL-C):
Good
cholesterol
Very low density
lipoprotein
cholesterol
(VLDL-C).
Low density
lipoprotein
cholesterol
(LDL-C):
Bad
cholesterol

21. FUNCTIONS OF CHOLESTEROL:
It is a fat-related substance as it does not produce energy, formed in
animal liver only, so not found in plant food (vegetable oils).
Structure of
adrenal & sex
hormones.
Synthesis of
vitamin D3.
Precursor of bile
salts which are
essential for fat
digestion.
Essential
component in
cell membrane.

22. NORMAL BLOOD LEVEL
Cholesterol
Total < 200 mg/dl
LDL-C <130 mg/dl
HDL-C
>40 mg/dl for
males.
>50 mg/dl for
females
Triglycerides
<150 mg/dl

23. EFFECT OF EXCESS FAT INTAKE
Overweight & obesity.
↑LDL-C & triglycerides in blood → atherosclerosis & CHD.
Diabetes mellitus type II & gall bladder stones.
Repeated heating of vegetable oils (USFA) →transformation into SFA
“junk foods with repeated frying of oils”.
Margarine which is trans-FA (hydrogenated saturated vegetable oils) & promotes
CVD as it ↑ LDL-C & ↓ HDL-C despite it does not contain cholesterol. Butter
contains cholesterol & SFA but it ↑ both LDL-C & HDL-C.

24. PROTEINS:
Proteins are formed
of amino acids
(C.H.O.N. atoms).

25. SOURCES OF PROTEIN (TYPES OF PROTEINS):
Complete proteins:
Contain the essential amino
acids.
Animal foods as meat, fish,
milk, eggs.
Incomplete proteins:
Not contain all the essential
amino acids & contain the
other non-essential amino
acids.
Vegetable foods as cereals,
legumes, peanuts.

26. PROTEIN REQUIREMENTS/DAY:
Adult
• 0.8 gm/kg BW
Infant & Child
• 2-3 gm/kg BW
Pregnant
• 2-3 gm/kg BW
Lactating
• 3 gm/kg BW

27. Reference
protein
It is an ideal
protein
Contains all the
essential A.A. in
optimal amounts
for human's
nutrition.
Fully digestible
& utilizable by
the body.
Examples:
human milk &
hen's egg.

28. FUNCTIONS OF PROTEINS
Body building & growth (formation, maintenance and
repair of cells).
Formation of essential components: hormones,
enzymes, immune cells, immunoglobulins &
hemoglobin.
Regulation of fluid movement of blood by control of
osmotic pressure.
Regulation of acid-base balance (control movement
of chemical ions in & out of the cells).
Production of energy: 1 gram → 4 kcals.

29. DEFICIENCY OF PROTEINS:
In children:
growth
retardation,
wasting
(Kwashiorkor).
Nutritional
oedema.
Impaired
immunity &
more
susceptibility
to infections.
General muscle
weakness &
poor wound
healing.
Apathy &
depression.

30. WATER
Functions of Water:
Aids in digestion,
absorption, circulation
& excretion processes.
Serves as a solvent for
body constituents & as
a medium for all
chemical reactions in
the body.
Carries nutrients to &
waste products from
cells as a part of the
blood.
Regulates body
temperature.
Involves with
lubrication of the
moving parts in the
body.
Water requirements: “Adults : 1ml/K.cal., Infants: 1.5 ml/K.cal”.

32. Vitamins
• Essential compounds that can’t
be manufactured by the body
in sufficient amount & have to
be supplied by food.
• Classified into:
Water-soluble vitamins:
Vitamins B group & Vitamin
C.
Fat-soluble vitamins:
Vitamins A, D, K, E.
“Absorbed from the intestine
with the dietary fat through the
lymphatic system & stored in
liver & not excreted in urine”.
Minerals (essential elements)
• Inorganic elements
• Classified into:
Major minerals: as calcium
phosphorus, sodium, chlorine,
potassium, magnesium and
sulpher.
Trace elements: as iron, zinc,
iodine, selenium, manganese,
chromium and copper.

33. Fat-sol. Vit. & sources Functions Deficiency
Vit. A (Retinol)
- Precursor: carotene
In: Liver, Butter, egg yolk, Dark green leafy
vegetables, Deep yellow & orange vegetables
and fruits
- Constituent of visual
purple.
- Necessary for growth and
reproduction
-Night blindness.
-Xerophthalmia
keratomalacia.
-Rough dry skin.
-Retarded growth.
Vit. D.:
- [Ergocalciferol (D2)] - [Cholecalciferol (D3)]
-7-dehyrocholesterol (in skin)
- formed by U.V.R in the skin
In:- Cod liver oil -egg yolk -fish with bones
(salmon)
-Promotes absorption of
calcium & phosphorus.
-Favors deposition of
calcium in bones.
-Reduces excretion of
phosphorus in urine.
-Rickets (children).
-Osteomalacia (adults)
-Osteoporosis.
Vit. E (Tocopherol):
Whole grain cereals, Legumes, nuts, fish, Green
leafy vegetables
- Antioxidant
- Hemopoiesis (protects
RBCs from haemolysis)
-Anemia in premature
infants
-RBCs hemolysis
Vit. K (Mendione):
Dark green leafy vegetables, Egg yolk, cheese,
Green tea
- Synthesized by intestinal bacteria
- Formation of
prothrombin and other
clotting factors.
- Hemorrhage

34. Vit. B1 (Thiamin):
Whole grains -yeast -Organ meats -
legumes
- Helps in carbohydrate metabolism
- Promotes good functioning of nervous
system and other systems.
- Beri-Beri.
- Polyneuritis.
Vit. B2 (Riboflavin):
Whole grains, yeast -Organ meats,
eggs, milk, milk products, green leafy
vegetables
Helps in metabolism of carbohydrates,
proteins and fats.
-Angular stomatitis.
- Cheilosis - Cataract
-Tongue inflammation
Vit. B3 (Niacin):
Whole grain cereals -Legumes, yeast -
meat, meat organs
-Carbohydrate metabolism - Pellagra
- Depression
Vit. B12 (Cobalamin):
Animal source protein only as: meat,
milk, eggs.
- Hb Synthesis & Formation of RBCs.
-Folic acid metabolism
-Megaloblastic anemia
- Neuritis
Folic acid (Folacin):
Dark green leafy vegetables, legumes,
whole grain cereals, meats, eggs
- Formation of RBCs -Megaloblastic anemia
- Neural tube defect.
Vit. C (ascorbic acid):
Citrus fruits, tomatoes, strawberries,
green leafy vegetables, green peppers,
broccoli
- Antioxidant - Wound healing
-Collagen tissue formation -Iron
absorption.
-Connective tissues of blood vessels
- Scurvy - Anemia
-Swollen& bleeding
gums

35. Major minerals Functions Deficiency
Calcium (Ca++): Milk – milk products
- green leafy vegetables - sardines,
salmon with bones
-Bone and teath formation
- Aids in blood coagulation
-Helps in muscles contractions
-Aids in enzymatic functioning
-Rickets - Osteomalacia
- Osteoporosis -Poor blood
Clotting
Phosphorus (P3-): Milk – milk
products – egg yolk – meat – nuts –
legumes – whole grains
-Bone and teeth formation
-Energy metabolism
-Aids in acid-base balance
-Fragile bones -Stiff joints
Potassium (K+): Banana, orange,
apricots, carrots, potatoes –meats,
milk, milk products -legumes,
molasses, tea
-Muscles contractions
-Key role in acid-base balance
-Aids in enzymatic reactions
- ↓heart rate -bone
fragility
Sodium (Na+): (In sodium
chloride)Common salt, naturally in
vegetables and milk
-Maintenance of acid-base balance
-Control of muscle contractions
-disturbed muscle action
(muscle cramps)
Magnesium (Mg++): Dark green leafy
vegetables -whole grains, nuts-bran -
banana – apricots - sea foods -tea –
coffee
-Bone and teeth formation
-Protein synthesis & lipid metabolism
-Regulates heart beats
-C.N.S. problem, as: confusion,
apathy, hallucinations -
Arrhythmia
-Cramps -Tremors

36. Minerals “Trace elements” Functions Deficiency
Iron (Fe+++):
Haeme sources: liver, red meat
Non haeme source: Dark green leafy
vegetables, legumes, whole grains,
molasses, dried fruits
-Essential for formation of
haemoglobin (in RBCs)
-Part of enzymes and proteins.
-Iron deficiency
anemia
Selenium (Se): Meat, eggs, liver,
whole grain cereals, sea foods, garlic
-Antioxidant -↓ cancer risk
-Plays a role in prevention of HIV
replication
-Plays a key role in immune system
Iodine (I-): Fish in salt, water,
vegetables grown in iodine-rich soil
-Regulates energy metabolism as a
part of thyroid hormone
-Endemic goiter
-Cretinism.
Zinc (Zn++): Whole grains, wheat
germ, liver, yeast, sea foods, milk
-Growth & reproduction
-Immunity, neurological functions
& smell acuity.
-Retarded growth &
sexual maturation
Copper (Cu++): Shellfish, liver, nuts,
while grains, chocolates
-Information & survival of RBCs
-In lipid metabolism
-Anemia
-CNS problems
Chromium (Cr+++): Liver, whole
grains cheese, legumes, yeast
-Activate enzymatic action
-Enhances removal of glucose from
blood
-CNS problems
-DM aggravation

37. PHYTOCHEMICALS

38. These are 1000 or more newly recognized non-nutritive
plant chemicals neither vitamins nor minerals and have
disease preventive effects.

39. FUNCTIONS OF PHYTOCHEMICALS
• Flavonoids (apples & green tea): ↓cancer lung risk.
Lycopene (tomatoes & pepper): ↓cancer prostate risk
“antioxidant effect 2 times as powerful as vit.A”.
Antioxidant & Anti-
cancer:
• Reduce menopausal symptoms, osteoporosis and cancer
risk.
Hormonal &
Enzymatic
stimulation effect
• Grapes, nuts, rosemary, tea, whole grains, legumes and
soybeans.
Anti-inflammatory &
Anti-blood clotting
effect
• Green tea.
↓ LDL-C & ↑ HDL-C