Nutrition, nutritional status & nutritional significance of Carbohydrate, protein & lipids

1. D. Subh
a
shini
Asst. Professor
Dept of Biochemistry

2. Nutrition: the study of food, including -
How food nourishes our bodies ?
How food influences our health ?
Nutrition is a relatively new discipline of science.
WhatisNutritionalBiochemistry?

3. Nutrition contributes to wellness.
Wellness: the absence of disease Physical, emotional, and
spiritual health
Critical components of wellness: Nutrition Physical activity
Nutrition can prevent disease.
WhyisNutritionImportant?

4. Essential substances that the body needs in order to grow and stay healthy.
Compounds in food essential to life and health.
the chemicals in foods that are critical to human growth and function
Six categories of nutrients :
WhatAreNutrients?

5. Nutrients
Classi
f
icationof
Nutrients
Macro
Nutrients Micro
Nutrients
Non-
Essential
Nutrients
Essential
Nutrients

6. Nutrients
Macro
Nutrients Micro
Nutrients
Non-
Essential
Nutrients
Essential
Nutrients

7. WhatAreMacro&MicroNutrients?

8. BasicFoodGroups

9. • Condition of health influenced by
utilisation of nutrients
• Optimal Nutrition
• Mal-nutrition
• Under Nutrition
• Over Nutrition
• Imbalanced Nutrition
• Speci
f
ic De
f
iciency
NutritionalStatus

10. Mal-Nutrition
OverNutrition
UnderNutrition

12. • Energy is the capacity to do work (or produce heat).
• We measure energy in kilocalories (kcal) or joules
• Calories = amount of energy required to raise the temperature
of 1g of water by 1oC
• Joule (J) = SI unit of energy
Energy FromNutrients

14. 🌽Chief source of energy
🌽2 categories of CHO (nutritional point)
🌽CHO utilised by body
Ex: starch, glycogen, sucrose, lactose, fructose
🌽CHO not utilised by body
Ex: cellulose, hemicellulose, pectin, gum
🌽Requirement : 40% of caloric need of body
Carbohydrates

15. 🍬Major Source of Energy : Contribute 60 - 70% of total caloric requirement of the
body
🍬Absolute Requirement by Brain : Brain & CNS depend on glucose - prolonged
hypoglycaemia cause irreversible brain damage.
🍬Protein Sparing Action : CHO rescue wasteful expenditure of protein for caloric
purpose.
🍬Source of Energy for Heart Muscle
🍬Promotes Growth of Good Bacteria : Lactose promotes growth of desirable
bacteria
🍬Structural Component : exoskeleton of insects, cell wall of microorganisms
NutritionalSigni
f
icance

16. 🍭Oxidation of Fat : Fat burns in a fuel of CHO
🍭Synthesis of Pentoses: DNA, RNA, NAD, FAD - pentoses produced from
CHO metabolism.
🍭Synthesis of Fat : excess of CHO stored as fat in adipose tissue
🍭Role in Muscle : major energy source for muscular activity
🍭Role in Liver : detoxify, influence protein & fat metabolism
🍭Synthesis of Aminoacids : provide carbon skeleton
🍭Non-digestible CHO : Essential for bowel movement, prevent
constipation, lower cholesterol absorption, improves glucose tolerance

18. 🥬Complex carbohydrate-not digested by human enzyme
🥬Ex: hemicellulose, cellulose, lignins, pectin, etc.,
🥬Types :
🥬Insoluble Fibre : indigestible & insoluble in water
Ex: cellulose, hemicellulose, lignins
🥬Soluble Fibre : indigestible but soluble in water
Ex: pectin, gums, mucilages
🥬Sources : fruits, leafy vegetables, wheat legumes, rice bran
🥬RDA : 30g/day
DietaryFibre
Non Digestible C
a
rbohydr
a
te

19. 🍌Prevents Constipation : absorb 10-15 times its own weight of water -
draws fluid into lumen - increasing bowel motility
🍌Decreases GIT cancer : in evidence of GIT cancer is low in vegans due to
f
ibre
🍌Eliminate Bacterial Toxin : adsorption toxin produced by bacteria &
helps easy expulsion
🍌Satiety Value : adds weight to food- sensation of fullness
🍌Reduce Plasma Cholesterol : decrease absorption of cholesterol
from intestines
🍌Improves Glucose Tolerance : decreases the rate of glucose absorption
from intestine.
NutritionalSigni
f
icance

20. (Lipids)

21. Lipids are a family of organic compounds that are mostly
insoluble in water
Lipids

22. TypesofLipids
• Make up 90% of
dietary lipid
• Commonly referred
as fat or oil
• Source : butter,
fried food, cream,
cheese,meat, etc,
• Make up only 2%
of dietary lipid
• Water soluble
• Found in plant &
animals
• S y n t h e s i s e d i n
body
• B e s t k n o w n -
cholesterol
• Very small % in diet
• Most of it produced
by body
TG PL STEROL

23. 🧀Energy : lipids have high calori
f
ic value. 1g of fat provide
9.3kcal
🧀Food Reserve : stored as TG in adipose tissue
🧀Structural Component : important constituent of cell
membrane
🧀Heat Insulation : fat deposits in subcutaneous layer in
acquatic and polar animals - provide insulation
🧀Protection : visceral fat - surrounds vital organs
NutritionalSigni
f
icance

24. 🧀Source of Vitamins : vegetable fat - source of vit E, animal fat -
source of vit A
🧀Absorption of Vitamins : essential for absorption of fat
soluble vitamins - A,D,E,K
🧀Source of EFA : vegetable fat - rich source of EFA & linoleic
acid
🧀Satiety Value : improves palatability, gives feeling of fullness

25. 🧀 Present in plasma as lipoprotein
🧀 Involved in transport of fat & cholesterol
🧀 Part of enzymes - cytochrome oxidase, succinctly oxidase
🧀 Important constituent of cell membrane- influence
permeability
🧀 Essential component of thromboplastin
🧀 Essential component of CNS - help form nerve cell
membranes, insulate neurons, and facilitate the signaling of
electrical impulses throughout the brain.
Phospholipids

26. 🧀Precursor - bile acid, steroid hormones
🧀Precursor - dehydrocholesterol - converted into vitD3 in body
🧀Essential component of cell membrane- maintain condition
🧀Present in large amount in nerve tissue - essential for its
function
Cholesterol

27. 🧈Unsaturated FA that cannot be synthesised by the body, hence must ingest
because the body requires them for good health but cannot synthesize
them.
🧈"essential fatty acid" refers to fatty acids required for biological
processes but does not include the fats that only act as fuel.
🧈Only 2 FA are known to be EFA for human - alpha linolenic acid ( omega 3
FA), linolenic acid (omega 6 FA)
🧈Source :
🧈Oils - vegetable,
f
ish, sunflower, cotton seed, corn, soya bean
🧈Butter, fat of meat
🧈RDA : 30% of dietary fat should be PUFA
EssentialFattyAcid(EFA)

28. 🧈Structural component of biological membranes
🧈Participate in transport and utilisation of cholesterol
🧈Prevent accumulation of fat in liver
🧈Required for synthesis of prostaglandins
🧈Maintain proper growth & reproduction
🧈Omega 6 & omega 3 FA have anti inflammatory & anti-thrombogenic
properties
🧈Posses bactericidal activity against common pathogens like
staphylococcus & streptococcus
🧈Brain & nervous tissue contain arachidonic acid
Functions

29. ๏Phrynoderma (Toad Skin ) - scaly dermatitis on posterior &
lateral parts of limbs & back
๏Affects -
๏reproduction & lactation
๏cell integrity
๏function of certain enzymes
๏cholesterol transport
๏Increases the risk of CHD (Coronary Heart Disease)
De
f
iciency

31. 🍗 Protein is an important part of a healthy diet.
🍗 Proteins are made up of chemical 'building blocks' called amino acids.
🍗 Your body uses amino acids to build and repair muscles and bones and to
make hormones and enzymes. They can also be used as an energy source.
🍗 Some amino acids can be made by your body – there are 11 of these and they’re
known as non-essential amino acids. ex : arginine, cystine, glycine, proline,
tyrosine
🍗 There are nine amino acids that your body cannot make, and they are known
as essential amino acids. You need to include enough of these in your diet so
that your body can function. ex : histidine, isoleucine, lysine, methionine,
phenylalanine, threonine, tryptophan, valine.
Protein

32. Nutrition
a
l Cl
a
ssi
f
ic
a
tion of Protein
COMPLETE
PROTEIN
posses all essential a.a in
required proportion
Ex : egg albumin, milk
casein
PARTIALLY
INCOMPLETE
PROTEIN
partially lack one or more
essential a.a
Ex : wheat & rice ptn
(lack try, thr)
INCOMPLETE
PROTEIN
completely lack one or
more essential a.a , do not
aid in growth
Ex : gelatin (lack trp),
zein (lack trp, lys)

33. ๏Animal Source : meat,
f
ish, egg, milk
๏Plant Source : pulses, oil seeds, nuts
๏Rich source - Soya bean - about 40% ptn
๏Moderate source - Cereals (6-12%) & millets (10%)
๏Poor source - vegetables, fruits, roots & tubers
Diet
a
ry Source & RDA of Protein

34. 🍼Structure: fundamental basis of cell structure & its functions.
🍼Growth & Maintenance of Tissue : concerned with growth & tissue repair.
🍼Formation of Essential Body Components: all enzymes & many hormones are proteins,
all substances responsible for blood clotting, muscle contraction, vision are protein.
🍼Transport of nutrients : across intestinal wall to blood & from blood to tissues.
🍼Regulation of water balance : maintain the fluid content
🍼Regulation of pH : serve as buffer
🍼Defence & Detoxi
f
ication : defensive proteins of immune system - antibodies; enzymes
in liver detoxify toxins in food
🍼Source of energy : 4kcal/g
Functions of Diet
a
ry Protein

35. 🍼Regulation of body process :
🍼Immune proteins : antibodies
🍼Hormones
🍼Enzymes
🍼Nucleo proteins
🍼Contractile proteins - actin & myosin
🍼Blood proteins - haemoglobin, serum albumin & globulin