The document discusses fats, including their classification as saturated, unsaturated, and polyunsaturated fatty acids; functions such as providing energy, insulating the body, and absorbing fat-soluble vitamins; recommended daily intake which is 20-35% of calories from fats including monounsaturated, polyunsaturated, and saturated fats; and digestion and absorption which involves emulsification in the small intestine and hydrolysis by pancreatic and intestinal lipases into fatty acids and glycerol.

1. VIJAYSINH MOHITE PATILCOLLEGE OFNURSINGAND
MEDICALRESEARCH INSTITUTE,AKLUJ
BSC NURSING SEMESTER– II
APPLIED NUTRITIONAND DIETETICS
UNIT- 4 FATS
PRESENTED BY,
MRS. SANAMBI SHAIKH
MSC NURSING (OBG)

3. INTRODUCTION
• Fats are best known members of a chemical group called
the lipids.
• They are characterized by greasy feel, insolubility in
water and solubility in some organic solvent like ether,
chloroform, benzene etc.
• They are more concentrated source of energy providing
two and half times more energy that carbohydrates and
proteins.
• It is a macronutrients.
• Fats are made up of glycerol and fatty acid.
• Fats are provides 9 kcal per 1 gram.

4. FATTYACIDS
• Fats yield fatty acids and glycerol on hydrolysis.
• Fatty acids are classified according to the presence and
number of double bonds in their carbon chain.
• The fatty acids may be saturated, unsaturated and
polyunsaturated.
• The flavour and hardness of fat depend on the kinds and
amounts of fatty acids present in it.

5. Classification of fatty acids
1. Saturated fatty acids –
each carbon atom in the fatty acid carries all the
hydrogen atoms possible. They have single bonds between
carbon atoms.
e.g. animal fats , vegetable – coconut and palm oil.
2. Unsaturated fatty acids –
the full complement of hydrogen atoms is not received
in unsaturated fatty acids. This leads to the formation of double
bond between the atoms so they have one or more double
bonds between the carbon atoms.
Unsaturated fatty acids are further divided into two –
Monounsaturated
Polyunsaturated

9. Calorie value
• 1 g fat – 37 KJ (9Kcal)
• 1 g carbohydrate – 17 KJ (4Kcal)
• 1 g protein - 17 KJ (4Kcal)
• 1 g alcohol (ethanol) – 29 KJ (7Kcal)
• 1 g dietary fiber – 8 KJ (2Kcal)

10. Functions of fats
• Energy
• Thermal insulation
• Protein sparing action
• Protection of vital organs
• Absorption of fat soluble vitamins
• Essential fatty acids
• Satiety value
• Synthesis of hormones
• Precursors of prostaglandins

12. FAT REQUIREMENT - RDA
• The dietary reference intake for fat in adults is 20% to 35% of
total calories from fat. That is about 44 grams to 77 grams of
fat per day if you eat 2,000 calories a day. It is recommended
to eat more of some types of fats because they provide health
benefits.
• Monounsaturated fat – 15 to 20%
• Polyunsaturated fat – 5 to 10%
• Saturated fat – less than 10%
• Cholesterol – less than 300 mg per day

13. Digestion and absorption
Buccal cavity
Saliva contains no lipase, therefore no fat digestion occur in
buccal cavity
Stomach
Gastric lipase hydrolyses only small amount of fat into
monoglycerides and fatty acids
Small intestine

14. • Fat bile emulsified fat
• Emulsified fat pancreatic lipase fatty acid + diglyceride
• Diglyceride pancreatic lipase fatty acid + monoglyceride
• Monoglyceride pancreatic lipase fatty acid + glycerol
• Digestion in intestine with the help of intestinal lipase
• Emulsified fat intestinal lipase monoglycerides + fatty acid