Carbohydrates and lipids are important macronutrients that provide energy and serve structural functions in the body. Carbohydrates include sugars, starches, and fibers that provide the main energy source. Lipids are composed of triglycerides, fatty acids, phospholipids, and sterols. They function as stored energy, insulation, and help with vitamin absorption. Certain fats like saturated and trans fats can increase heart disease risk if consumed in excess, while unsaturated fats are generally healthier. Cholesterol is transported between tissues and the liver within lipoproteins and is involved in cell membrane synthesis and hormone production.

1. CARBOHYDRATES
& LIPIDS
Lesson 3:

2. CARBOHYDRATES
are the main energy
source of the body.

3.  Carbohydrates (CHO) are formed of
carbon, hydrogen, and oxygen atoms
with a ratio of 1:2:1.
 The dietary carbohydrates include
the sugar, starch, and fibers.

6.  Oligosaccharides are chains of 3-10
monosaccharides. (“Oligo” = few)
 Polysaccharides are the largest unit
of carbohydrates (“Poly” = many)
Monosaccharides can also form larger
carbohydrates such as:

8. DISACCHARIDES
– double sugar made up of two simple sugars
chemically combined.
• Sucrose (table sugar) = glucose + fructose
• Lactose (milk sugar) = glucose + galactose
• Maltose (malt sugar) = glucose + glucose

9. POLYSACCHARIDES
– a carbohydrate made up of many
simple sugars chemically combined.
Also called “complex carbohydrates”

10. POLYSACCHARIDES
• Starch - energy storage for plants.
• Cellulose (fiber) – contained within cell
walls of plants (give structure).
• Glycogen – energy storage for animals
(mostly found in the muscle tissue)
• Chitin - exoskeleton of some animals.

11. REGULATION OF BLOOD GLUCOSE
Insulin and glucagon help maintain
blood sugar levels. Glucagon helps
prevent blood sugar from dropping,
while insulin stops it from rising too
high.

12. LIPIDS
• Lipids function as stored energy,
insulation for the body, and assist
absorption of certain vitamins.
• Lipids are large molecules that can
be categorized as fats or oils.

13. LIPIDS
• Lipids are composed of
triglycerides.
• These molecules are made up of
carbon, hydrogen, and oxygen
atoms

15. TRIGLYCERIDES
- most common type of fat found in
the human body and in food. They
consist of three fatty acids attached
to a glycerol molecule. Triglycerides
serve as a major source of energy and
are stored in adipose tissue (body fat)
for later use.

16. - are the building blocks of fats. They are
organic molecules consisting of a long
chain of carbon atoms with a carboxyl
group (-COOH) at one end. Fatty acids can
be saturated or unsaturated, and their
structure determines their physical
properties and health effects.
FATTY ACIDS

17. - are a type of fat in which the fatty acid chains
lack double bonds between carbon atoms. They
are typically solid at room temperature and are
found primarily in animal products like meat
and dairy, as well as some plant sources such as
coconut oil and palm oil. Consuming excessive
amounts of saturated fats may raise cholesterol
levels and increase the risk of heart disease.
SATURATED FATS

18. - are fats that contain one or more double
bonds in their fatty acid chains. They are
usually liquid at room temperature and are
found in plant-based oils, such as olive oil,
canola oil, and avocados. Unsaturated fats are
generally considered healthier than saturated
fats and can help reduce the risk of heart
disease when consumed in moderation.
UNSATURATED FATS

19. - also known as trans fats, are unsaturated fats
that have been chemically altered through a
process called hydrogenation. This process turns
liquid oils into solid fats and increases their
shelf life. Trans fats are commonly found in fried
and processed foods and have been linked to an
increased risk of heart disease. It is
recommended to minimize or avoid the
consumption of trans fats.
TRANS FATTY ACIDS

20. - are types of unsaturated fats that the
body cannot produce on its own and must
be obtained from the diet. The two main
essential fatty acids are omega-3 and
omega-6 fatty acids, which have important
roles in the body's functions, such as
regulating inflammation, supporting brain
health, and maintaining healthy skin.
ESSENTIAL FATTY ACIDS

21. - are polyunsaturated fats that are essential for
the body. Omega-3 fatty acids are found in fatty
fish (e.g., salmon, sardines), flaxseeds, and
walnuts, and have anti-inflammatory properties.
Omega-6 fatty acids are found in vegetable oils
(e.g., soybean oil, corn oil) and play a role in
promoting inflammation when consumed in
excess. It is important to maintain a balance
between omega-3 and omega-6 fatty acids for
OMEGA-3 AND OMEGA-6 FATTY ACIDS

22. - are a class of lipids that are a major
component of cell membranes. They
consist of a glycerol molecule, two fatty
acids, and a phosphate group.
Phospholipids have a unique structure that
allows them to form a bilayer in cell
membranes, providing a barrier between
the cell and its environment.
PHOSPHOLIPIDS

23. - Phospholipids are found in various foods,
particularly in animal-based sources such as
eggs, meat, and dairy products. They are also
present in plant-based foods like soybeans and
sunflower seeds. Phospholipids act as
emulsifiers, helping to mix oil and water-based
substances together in foods like dressings and
sauces.
PHOSPHOLIPIDS IN FOODS

24. - Phospholipids play crucial roles in the
body, including forming cell membranes,
facilitating the transport of nutrients in
and out of cells, assisting in digestion and
absorption of dietary fats, and serving as
precursors for important signalling
molecules.
ROLES OF PHOSPHOLIPIDS

25. - Sterols are a type of lipid that have a
distinct molecular structure. The most
well-known sterol is cholesterol, which is
found in animal tissues and plays various
roles in the body. Unlike triglycerides and
phospholipids, sterols do not contain fatty
acids.
STEROLS

26. - Sterols are naturally present in small amounts
in various foods, primarily in animal products
such as meat, eggs, and dairy. However, the
most significant dietary source of sterols is
plant-based foods, especially vegetable oils,
nuts, and seeds. Plant sterols, such as beta-
sitosterol, have been shown to have cholesterol-
lowering effects when consumed in sufficient
STEROLS IN FOOD

27. - Cholesterol synthesis refers to the
production of cholesterol in the body,
primarily in the liver. The process involves a
series of enzymatic reactions that convert
simpler molecules into cholesterol.
Cholesterol synthesis is tightly regulated by
the body to maintain optimal levels.
CHOLESTEROL SYNTHESIS

28. - Bile Route: Cholesterol leaves the liver as
bile acids, which are stored in the
gallbladder. They are released during
digestion to help break down fats in the
small intestine. Some bile acids are
reabsorbed in the intestines and recycled
back to the liver, while others are
eliminated from the body through feces.
CHOLESTEROL’s ROUTES

29. - Bloodstream Route: Cholesterol
synthesized in the liver is transported in the
bloodstream as part of lipoproteins, mainly
VLDL and LDL. VLDL carries cholesterol and
triglycerides to tissues, while LDL delivers
cholesterol to cells. Excess LDL cholesterol
can contribute to artery plaque formation
and increase the risk of cardiovascular
CHOLESTEROL’s ROUTES

30. - Cholesterol is not soluble in blood, so it
needs to be transported through the
bloodstream by lipoproteins. Low-density
lipoprotein (LDL) carries cholesterol from
the liver to various tissues, while high-
density lipoprotein (HDL) helps remove
excess cholesterol from the tissues and
transports it back to the liver for excretion.
CHOLESTEROL TRANSPORT

31. - Fats play important roles in the body, including
providing a concentrated source of energy,
supporting the absorption of fat-soluble
vitamins, and serving as building blocks for cell
membranes and certain hormones. However,
consuming excessive amounts of certain types of
fats, particularly saturated fats and trans fats,
can increase the risk of heart disease and other
health issues.
HEALTH EFFECTS OF FATS

32. - On the other hand, consuming moderate
amounts of unsaturated fats, including
omega-3 fatty acids, can have positive
effects on heart health. It's important to
maintain a balanced and varied diet that
includes healthy fats while limiting the
intake of unhealthy fats.
HEALTH EFFECTS OF FATS

33. CHECK FOR UNDERSTANDING
1. B
2. B
3. C
4. A
5. A
6. B
7. C
8. A
9. D
10.E

34. THANK YOU, THAT’S
ALL.