1. Fats

2. Why do we need fats?
• Contribute to texture and taste
• Increase palatability of diet
• For meeting the needs of essential
fatty acids (linoleic acid n – 6 and
linolenic acid n – 3)
• Rich source of energy
• Promote absorption of fat soluble
vitamins
• Impart a feeling of fullness and
satisfaction and thus delay onset of
hunger.

3. Essential Fatty Acids
• Queen of Vitamins
• Poly Unsaturated Fatty Acids (PUFA)
• Linoleic acid (C18:2/n-6/PUFA) and
α Linolenic acid (C18:3/n-3/PUFA) –
must be present in a ratio of 5:1 to 10:1
• Omega 6 to Omega 3 (n6 : n3) ratio of 5:1
is desirable

4. Essential Fatty Acids
• High Omega 6 and low omega 3 ratio as
in ground nut, sunflower, safflower oils
(56:1) can predispose to
– free radical injury,
– angiotoxicity,
– impaired immune function,
– reduced glucose tolerance,
– increased platelet aggreagation and
– albuminuria

5. Essential Fatty Acids
• Omega 6 and Omega 3 ratio
– In coconut oil, [PUFA is only 2%] but this
ratio is <5:1 (but more MCTs)
– In ghee it is 3:1
– Mustard oil 1.5:1

6. Essential Fatty Acids
• Omega 3 or n-3
– In coconut oil, [PUFA is only 2%] but this
ratio is <5:1 (but more MCTs)
– In ghee it is 3:1
– Mustard oil 1.5:1

7. Long Chain Fatty Acids
EFAs are converted to LCFAs by a series of
chemical reactions called elongation and
desaturation.
• LCPs from n-6 series derived from linoleic
acid are
– arachidonic acid (ARA) and
– adrenic acid (ADA).
• LCPs from n-3 series derived from alpha
linoleic acid are
– ecosa pentanoic acid (EPA) and
– decosa hexanoic acid (DHA).

8. Long Chain Fatty Acids
EFAs are converted to LCFAs by a
series of chemical reactions called
elongation and desaturation.
• LCPs are the building blocks of brain
lipid.
• Deficiency of LCPs may lead to
comorbid conditions like dyslexia,
dyspraxia and hyperactivity

9. Types of fat
• Visible :
– Fats that are used as such at the
table or in cooking
• Eg: Veg. oils, vanaspathi, ghee,butter
etc.
• Invisible :
– Fats that are present as and integral
components of different foods
• Eg. : cereals, animal foods

10. Component of fat
• Total should be 15 – 30 % and 1-3 %
of calories should be from EFAs
• Avg. Indian foods supply 25-30%
calories as fat. Diets of young children
and adolescents should contain only
25 g/d of fat
• Not more than 10% of energy should
be from essential fatty acids /SFA and
10% should come from MUFA and
10% from PUFA

11. Fatty Acids - Types
• Saturated: Lauric acid (C12), Myristic
acid (C14), Palmitic acid (C16) and
Stearic acid (C18)
– Animal fats
– Short and medium chained saturated FAs
are easily absorbed
– Excess of MCTs can be atherogenic
• Monounsaturated fats:
– Oils from palm, seseme, groundnut,
cotton seed, olive.

12. Fatty Acids - Types
• Polyunsaturated fats:
– Only in plant foods
– All vegetable oils rich in Linoleic (n-6)
– α- linolenic (n-3) is present only in
mustard and soyabean oils and as
invisible oil in legumes/pulses, mustard
and fenugreek seeds (methi) & GLVs
– Fish and fish oils provide biologically
more active form of n-3 linolenic acid

13. Fatty acid compositions
Item SFA % MUFA % PUFA %
n6 n3
Coconut oil 92 6 1.6 0.4
Corn oil 13 25 61 1
Groundnut oil 18 49 33 0
Olive oil 14 8 1
Sunflower oil 11 20 69 0
Safflolower oil 10 13 77 0
Palmolein 40 48 11 1
HVO 76 19 3 2

14. SATURATED MONO
UNSATURATED
POLY UNSATURATED
LINOLEIC (N - 6) LIONOLENIC (N-3)
•Coconut
•Palm kernel
•Ghee
•Butter
•Vanaspathi
•Red palm oil
•Palmolein
•Groundnut
•Ricebran
•Saseme
Low:
• Red palm oil
•Palmolein
Medium:
•Groundnut
•Ricebran
•Seseme
•Mustard
•Soya bean

15. Medium Chain Triglycerides
• C8 - C10 Fatty Acids
• They are absorbed directly into the portal
vein even during fat malabsorption.

16. Cholesterol
• Essential component of body tissues and
lipoproteins
• Forms nearly 0.2 % of body weight
• It has no calorific value
• Hypercholesterolemia – esp. LDL predisposes
to coronary heart disease
• Heredity, smoking, sedentary habit, emotional
stress, hormonal imbalance, diet, diabetes etc.
predispose to hypercholesterolemia.

17. Cholesterol
• Endogenous : Synthesized from 2 carbon
fragments like acetate, acetic acid, acetyl
CoA, etc.
• Exogenous : Derived from food

18. Cholesterol
• Excess cholesterol is converted to bile acids and
excreted into intestine and eliminated as coprosterol
• Dietary fiber reduced cholesterol level
• Cholesterol is present in bound and free forms in a
ration of 1:3
• Bound to esters of fatty acids or lipoprotein (LDL)
cholesterol – 70%
• That bound to alpha lipoprotein is high density
lipoprotein (HDL) cholesterol – 30%
• Small amounts - bound to very low density lipoproteins
(VLDL) and rest to intermediate low density
lipoproteins (ILDL) and very high density lipoproteins
(VHDL)