BASICS ABOUT CARBOHYDRATES AND LIPIDS

1. CARBOHYDRATES
LIPIDS

2. Carbohydrates
Aldehyde or ketone compound with
multiple hydroxyl gp
include sugars, starches, and fiber.
Provides energy store in our body
[4 kcal/1gm]
Structural element of cell wall of
bacteria/plant/arthropods
Linked to many protein n fat
compound (Glycoprotein in
membrane)
2

3. 3

4. Simple Carbohydrates
Monosaccharide
C6H12O6
4

5. Simple Carbohydrates
Glucose
Fructose
• sweetest sugar
• found in fruits and
honey
• added to soft drinks,
deserts
• mild sweet flavor
• known as blood sugar
• essential energy
source
• found in every
Galactose
disaccharide and
• hardly tastes sweet
polysaccharide
• rarely found naturally as a
single sugar
5

6. Maltose
DISACCHARIDES
pairs of the monosaccharide's
C12H24O12
2 glucose units
• Germinating grains
• Sweet potatoes
• Dates
• beer
Sucrose:
– fruit,
– vegetables,
– grains
Lactose : glucose+galactose
main carbohydrate in milk
6

7. Complex Carbohydrates
glycogen, starch, fiber
7

8. Glycogen
Complex
Carbohydrates
• limited in meat and not found in plants
– not an important dietary source of carbohydrate
• BUT
– all glucose is stored as glycogen
• Long chain Must be broken down to be used by
the body
8

9. Starches
Complex
Carbohydrates
• plant foods (potatoes, beans, peas, and grains
such as rice corn and wheat).
• body hydrolyzes plant starch to glucose
9

10. Fiber
Complex
Carbohydrates
• Nor- starch polysaccharides
– found in grains, fruits and vegetables
10

11. Fiber types
• cellulose
• pectins
• lignins
• Plant gums
• mucillage
11

12. Fiber
• Fiber: provides little energy and is indigestible.
Absorbs water-increase bulk of stool & soften stoolpromote bowel movements
- alleviate constipation- formation of gas & toxic
substances-Keeps your digestive tract healthy.
• Inhibits mutagen in colon-CA colon
• CHD- binds to BS-cholesterol
• Gum/pectin-PPBS
12

13. Carbohydrate Digestion
• begins in mouth
– chewing releases saliva
– enzyme salivary amylase hydrolyzes
starch to polysaccharides and maltose
• stomach
– no enzymes available to break down
starch
– acid does some breakdown
– fibers in starch provide feeling of
fullness
13

14. small intestine
Digestion
– majority of carbs digestion takes place here
– pancreatic amylase reduces carbs to glucose
chains or disaccharides
– specific enzymes finish the job
• maltase
– maltose into 2 glucose
• sucrase
– sucrose into glucose and fructose
• lactase
– lactose into glucose and galactose
14

15. large intestine
Digestion
–1-4 hours for sugars and
starches to be digested
–only fibers remain
• attract water, which softens
stool
–bacteria ferment some fibers
• water, gas, short-chain fatty
acids (used for energy)
15

16. Carbohydrate Absorption
• glucose can be absorbed in the mouth
• majority absorbed in small intestine
–active transport
• glucose and galactose
–facilitated diffusion
• fructose
16

17. 1
Intestine
Maintaining
Blood Glucose
Homeostasis
When a person eats,
blood glucose rises.
2
Pancreas
High blood glucose stimulates
the pancreas to release insulin.
Insulin
Insulin stimulates the uptake of
glucose into cells and storage
as glycogen in the liver and
muscles. Insulin also stimulates
the conversion of excess
glucose into fat for storage.
3
Liver
Fat cell
Muscle
4
5
Pancreas
As the body's cells use
glucose, blood levels decline.
Low blood glucose stimulates
the pancreas to release
glucagon into the bloodstream.
Glucagon
6 Glucagon stimulates liver
cells to break down glycogen
and release glucose into the
blood.a
Glucose
Insulin
Glucagon
Glycogen
Liver
a The stress hormone
epinephrine and other hormones
also bring glucose out of storage.
7
Blood glucose begins to
rise.
17

18. Imbalance
Diabetes: after food intake, blood glucose rises and is
not regulated because insulin is inadequate
Hypoglycemia: blood glucose drops dramatically
too much insulin, activity, inadequate food intake, illness
Starvation- inadequate supply of carbohydrates-
ketone bodies (fat fragments) are an alternate
energy source-excess ketones can lead to ketosis
Lactose Intolerance
intestinal bacteria feed on undigested lactose
produce acid and gas, lactose molecules attract water
cause floating, abdominal discomfort, diarrhea
18

19. Glycemic Index
• way of classifying food according to their
ability to raise blood glucose
• Rate and degree of blood sugar elevation
following consumption
19

20. Artificial Sweeteners
•Saccharin
•Aspartame
•Sucralose
•Neotame
Diabetic pt.
20

21. RDA
45-65% of total energy
intake
Daily Value is 300
grams per day
fiber intake: Daily
Value 25-<40 gm
added sugar = <10% of
energy intake
21

22. FAT

23. are the body’s main form of longterm energy storage.
 large molecules made up of FA and
glycerol
 Fatty acids are long chains of carbon
atoms attached to hydrogen atoms.
 Fats
23

24. Classification
Simple lipids -
TG
Compound lipid-
phospholipids
Derived lipid:-
sterols
• major class of dietary lipid
• in adipose tissue-coconut oil, palm
oil, cotton seed, butter, margarine
• minor portion of lipids in diet
• lecithin is most common
• important part of cell membranes
• Cholesterol
• sex hormones, Vit D
24

25. classification
Saturated fats
Lauric acid
Palmate
Stearic acid
• No double bond C-C
• solid at room temp
• Animal origin—
ghee, butter,
cheese, meat, fish..
– obesity, high
cholesterol levels,
increased risk of heart
disease.
25

26. Unsaturated fats
MUFA
 Oleic acid
PUFA
 Lenolenic acid
 Lenoleic acid
 Arachidonic acid
 Eicosapentenoic acid
Safflower oil
Corn oil
Sunflower
Soybean
Groundnut
Mustard
Palm
Cod
liver oil
26

27. Structure of lipoprotein
INTEGRAL APOPROTEINS
MONOLAYER OF PHOSPHOLIPID
AND CHOLESTERLOL
CHOLESTEROL
ESTERS
CORE
TRIGLYCERIDES
PERIPHERAL APOPROTEINS
27

28. Class
Source and function
Major
apoliproteins
Chylomicrons
(CM)
Intestine.
Transport of dietary TG to cell
A, B48,
C(I,II,III) E
Very low density
lipoproteins
(VLDL)
Liver.
Transport of endogenously
synthesised TAG
B100,
C(I,II,III) ,
E
Low density
lipoproteins
(LDL)
Formed in circulation by
partial breakdown of IDL.
Delivers cholesterol to
peripheral tissues
B100
High density
lipoproteins
(HDL)
Liver.
Removes “used” cholesterol
from tissues and takes it to
liver
A,
C(I,II,III),
D, E
28

29. Trans Fat

An unhealthy substance made through
the chemical process of partial
hydrogenation of oils.

flavor & stability of foods

Deep fried fast foods, cake, chips….
29

30. 30

31. Is there reason for concern?
 behave more like saturated fatty acids
◦ More atherogenic
◦ Takes many years to flush form body



◦
Raises the LDL
Lowers the HDL
making the arteries more rigid
causing major clogs in the arteries
creating insulin resistance-contribute to
DM
significantly increase the chance of heart
disease
31

32. Hydrogenation
Vegetable oil
vanaspati ghee
catalyst
Liquid
Drastically
semisolid form
keeping quality
EFA content
32

33. Refined oils
Refining & deodorizing of raw oil
 To remove free FA & rancid materials

Quality & taste
 costly
33

34. Uses of Fat
Energy- 9 kcal/gm
Insulation beneath skin
Support-Padding for organs
structural integrity of Cell membranes
Carry fat soluble vitamins
Precursor of Prostaglandin- vascular
homeostasis
Make food more palatable
34

35. Health Effects
Obesity
Phrenoderma-toad skin-due to
deficiency
CHD »atherosclesis
(cholestrol LDL)- >40% energy
supply form saturated fat
CA- colon/breast
35

36. Choice of cooking oil
PUFA [safflower/sunflower/corn oil]
MUFA
Ground-nut oil
Mustard oil
36

37. Know Your Lipid Profile
Fasting Blood Level
Level
Total Cholesterol
Ideal, Healthy
< 200 mg/dl
LDL-Cholesterol
< 100 mg/dl
HDL-Cholesterol
≥ 60 mg/dl
Triglycerides
< 150 mg/dl
37

38. 20-30 % of total energy intake
• [The ICMR has recommended a daily intake of not more than
20 % of total energy intake through fats]
>50% from vegetable oils
saturated fat <10%
trans fat
Cholesterol
PUFA
<1%
<300 mg/Day
6-10% of total energy intake
38

39. Thank you