nutrition

1. Basic principles of nutritional
science
Prepared by:
Dr.Mazen Alshaghdari

2. Outline
 Nutrition & health promotion (basic definitions,
importance of a balanced diet)
 Functions of nutrients in food
 Good nutrition:
1) Optimal nutrition
2) Under nutrition
3) Malnutrition
4) Over nutrition
 Nutrient & food guides for health promotion

3. Basic definitions
 Nutrition: concerns the food people eat and how their
bodies use it.
 Nutrition: is a basic need that must be met for all
clients.
 Nutritional science: comprises the body of scientific
knowledge governing human foods requirements for
maintenance, growth, activity, & reproduction.
 Dietetics: is the health profession responsible for
applying nutritional science to promote human health
and treat disease

4. Basic definitions
 Registered dietitian: clinical nutrition specialist, he has
the major responsibility of nutritional care in patients
& clients.
 Health: is defined as absence of disease, and must
meeting basic human needs (physical, mental,
psychological, & social well-being).
 Wellness: seeks the full development of potential for
all persons.

5. Basic definitions
 Traditional & preventive approach to health:
- preventive approach: involves identifying risk
factors that increase a persons chances of
developing health problem.
- Traditional approach: only attempts change
when symptoms of illness or disease already
exist.

6. Importance of a balanced diet
 Food plays an important role in maintaining good
health and recovering from illness.
 Assessing a patients nutritional status & identifying
nutritional needs are primary activities in the
development of a health care plan.
 Signs of good nutrition: well developed body, Ideal
body weight, height, & good muscle development.
- Appetite, digestion, & elimination are normal.
 Calculation of ideal body weight: depend on height
- Every 60 inch give 100 bounds
- Every 1 inch above 60 we add 5 bound for female, &
6 for male.

7. Functions of nutrients in food
 The nutrients must perform the
following three basic functions within
the body:
1) Provide energy.
2) Build tissue
3) Regulate metabolic processes.

8. Energy sources
 Kilocalorie: is the measure of heat necessary
to raise the temperature of 1L of water 1 °C, 1
kcal= 1000 calories.
 Carbohydrates: such as starches & sugars,
consider primary source for heat & energy, also
may store energy as glycogen.
- Each gram of carbohydrate gives 4Kcal of
body energy (fuel factor).
- In a well balanced diet, carbohydrate should
provide about 45%-65% of the total Kcalories.

9. Energy sources
 Fats: either animal or plants sources,
provide the body secondary, or storage
form of heat & energy.
- Each gram of fat consumed yields
9Kcal.
- Fat should provide no more than 20%-
35% of the total Kcalories.

10. Energy sources
 Proteins: each gram gives 4Kcal.
- In a well balanced diet, protein should
provide about 10%-35% of total Kcal.
- Primary function of protein is tissue
building, some of it may be used for
energy if necessary.

11. Tissue building
 Proteins: dietary protein provides amino acids, which
are the building units necessary for constructing &
repairing body tissues.
 Vitamins & minerals: such as vitamin C which used to
develop cementing intracellular ground substance
(collagen).
- Collagen helps build strong tissue and prevents
tissue bleeding.
- Two major minerals (calcium, & phosphorus): they
help in building & maintaining bone tissue.
- Also iron, which contributes to building the oxygen
carrier hemoglobin in red blood cells.

12. Tissue building
 Fatty acids: derived from fat
metabolism, help build the central fat
substance of cell walls and promote
the transport of fat soluble materials
across the cell wall.

13. Regulation & control
 The multiple chemical processes in the body necessary
for providing energy & building tissue should be
regulated and controlled to maintain a smooth,
balanced operation.
 Vitamins and minerals are nutrients that help regulate
many body processes.
 Vitamins: many vitamins function as coenzyme
factors, which are components of cell enzymes, in
governing chemical reactions during cell metabolism
- Example: B-complex vitamins.
 Minerals: many minerals also serve as coenzyme.
- Example: cobalt, which is a central constituents of
vitamin B12, functions with this vitamin to combat
pernicious anemia.

14. Regulation & control
 Other nutrients: water & fiber consider
regulatory agents.
 Water: basic for our life, providing the
essential base for all metabolic
processes.
 Dietary fiber regulate the passage &
absorption of material through the
gastrointestinal tract.

15. Good nutrition
1) Optimal nutrition: means that a person receives and
uses substances that are obtained from a varied diet
of carbohydrates, fat, proteins, minerals, vitamins,
water, & dietary fiber in ideal amounts for the
specific individual.
2) Under nutrition: suboptimal diet, but this not mean
undernourished, still person can maintain health, but
has a greater risk for physical illness, also
nutritionally deficient people are limited in their
physical work capacity, immune system, function,
and mental activity.

16. Good nutrition
3) Malnutrition: when nutrient & energy intake
insufficient meet day to day needs or added
metabolic stress.
- Mostly we see in poor society. -
Vulnerable persons: pregnant women, infants,
children, & elderly adult).
4) Over nutrition: excess nutrient & energy intake
over time
- Harmful gross body weight: morbid obesity.

17. Thank you for listening