Biochemistry

1. NUTRITION

2. 
At the end of lecture students should be able
to:
Define nutrition
Discuss important nutrients
Define balanced diet
Understand importance of balanced diet
Describe dietary reference intake
Identify the energy requirement of body
LEARNING OBJECTIVES

3. 
The use of foods by organism is termed
as nutrition
The ability of an organism to use a
particular food material depends upon its
chemical compound composition & upon
the metabolic pathways available to
organism
NUTRITION

4. 
 The study of food or nutrients regarding:
• Digestion
• Absorption
• Transport
• Excretion
• Utilization by body
 It also concerned with the certain social, economic,
cultural and psychological implication of food
NUTRITION

5. 
It also covers the aspects of food related to its
preservation, marketing, processing and
distribution
Clinical aspects of nutrition covers the
problems associated to deficiency or excess
of nutrients in the body
NUTRITION

6. 
Nutrition can prevent disease
Nutrient deficiency diseases:
scurvy, goiter, rickets
 Diseases influenced by nutrition
chronic diseases such as heart disease
 Diseases in which nutrition plays a role
rickets, osteoporosis
Why is Nutrition Important?

7. 
Chemical substances in food that:
• Provide energy
• Provide materials for building body
parts
• Provide factors to regulate needed
chemical processes in the body
• Functions as anti-oxidants
NUTRIENTS

8. 
TYES OF NUTRINTS
MAJOR NUTRIENTS
A) Source of energy
• Carbohydrates
• Proteins
• Lipids
B) As source of essential
biochemical
• Essential amino acids
• Essential fatty acids
MINOR NUTRIENTS
1. Vitamins
2. Minerals
3. Water
4. Fiber

9. 
1. Carbohydrates : main source of energy
2. Proteins: repair and growth of the body
3. Lipids: provide energy, helps in storing energy and vitamins
4. Vitamins: helps in getting energy from carbohydrates,
proteins and lipids
5. Minerals: regulation of water balance, bone development
and maintenance
6. Water: helps in body processes such as digestion, absorption,
transport and making blood and other body fluid
7. Fiber: regulate intestinal motility, water absorption and
prevent constipation
Biochemical Role Of Nutrients

10. 
 “Diet that can be followed for a long period of time
& that will keep the body healthy”
 It is affected by:
i. Age
ii. Sex
iii. Level of activity
iv. Body surface
v. Climate
vi. Taste and desires
vii. Religious prejudice
viii.Social outcomes
BALANCED DIET

11. 
Carbohydrates
Proteins
Fats
Vitamins
Minerals
Water
 Fiber
Balanced Diet Must Contain

12. 
A person must have all these otherwise a
person will feel very tired and will not have
high or enough energy
If you take too much energy containing foods
you will become over weight which leads to
different diseases
BALANCED DIET

13. 
The balanced diet should provide the adult
weight 70 kg; with 2400 to 3000 calories per
day
• 1 gm of carbohydrate provide 4.6 k Calories
• 1 gm of fat provides 9.1 k calories
• 1 gm of protein provides 4.2 k calories
ENERGETICS OF BALANCED
DIET

14. 
60-70% of total energy should come from
CHO
20-35% of total energy should come from fats
10-15% of total energy should come from
proteins
According to %

15. 
While calculating the energy requirements,
we have to consider the energy required for:
i. Maintenance of basal metabolic rate
ii. Specific dynamic action or thermogenic
effect of food
iii. Extra expenditure for physical activities
Energy Requirement Of A
Normal Person

16. 
 “The basal metabolic rate (BMR) is the
energy required by an awake individual
during physical, emotional and digestive
rest”.
It is the minimal amount of energy required
to maintain life or sustain vital functions like
working of heart, circulation, brain function,
respiration etc.
BASAL METABOLIC RATE

17. 
Age
Sex
Temperature
Exercise
Fever
Thyroid hormones
FACTORS AFFECTING BMR
Normal value of BMR for adultmale of 70 kg 1800 k Cal
Adult femaleof 70 kg 1300 k Cal

18. 
Also called thermogenic effect of
food
“SDA refers to increased heat
production or increased metabolic
rate following intake of food”
SPECIFIC DYANMIC ACTION
(SDA)

20. 
Dietary reference intakes are composed of:
1. Recommended Dietary Allowances (RDA)
2. Adequate Intakes (AI)
3. Estimated Average Requirements (EAR)
4. Tolerable Upper Levels (TUL)
DIETARY REFRENCE INTAKES

21. 
“The average daily dietary intake level that is
sufficient to meet the nutrient needs of nearly
all (97-98%) healthy individuals in a group”
Does not include intake of those with any
disease
Must come from consumption of foods
(dietary), does not include intake from
supplement
RECOMMENDED DIETARY
ALLOWANCE (RDA)

22. 
“ A value based on observed or experimentally
determined approximations of nutrient intake
by a group (or groups) of healthy people used
when RDA can not be determined”
ADEQUATE INTAKE (AI)

23. 
“ A nutrient intake value that is estimated to
meet the requirement of half of the healthy
individuals in a group”
This is restricted to healthy persons only
ESTIMATED AVERAGE REQUIREMENT
(EAR)

24. 
“ The highest level of daily nutrient intake
that is likely to pose no risks of adverse health
effects to almost all individuals in the general
population. As the intake increases above the
TUL, the risk of adverse effects increases”
TOLERABLE UPPER LEVEL OF
INTAKE (TUL)

25. 
Food Guide Pyramid

26. 
Cholesterol
Plasma lipoproteins
Saturated fatty acids
Polyunsaturated fatty acids
Monounsaturated fatty acids
Antioxidants
Alcohol consumption
Fiber
DIET AND CORONARY
ARTERY DISEASE

27. 
 Diet influences certain type of cancers e.g.
Esophagus, stomach, colon, prostate, breast and lung
 Consumption of saturated fats associated with
increased risk of cancers especially colon, breast and
prostate
 Increase consumption of vitamins like vitamin C
reduced risk of lung, stomach, esophagus and oral
cavity cancer
 High fiber diet reduced risk of colon cancer and
diverticulitis
DIET AND CANCER

28. 
 Group of related disorders that include marasmus,
kwashiorkor, and intermediate states of marasmus-
kwashiorkor.
 PEM is due to “food gap” between the intake and
requirement.
 DEVELOPEDCOUNTRIES
chronic illness from severe infection, trauma, major
surgery
 UNDER DEVELOPED COUNTRIES
inadequate intake of proteins
PROTEIN-CALORIE
MALNUTRITION

29. St.Ann's Degree College for Women

30. 
CIRCUMSTANCES REQUIREMENTS
Healthy Females
At rest 1600 kcal
Light work 2000 kcal
Heavy work 2250 kcal
Healthy Males
At rest 2000 kcal
Light work 2700 kcal
Heavy work 3500 kcal
Daily Energy Requirements