Fat presentation

1. Lecture 3 . Fats
Rusudan Kvanchakhadze, Head of the Clinical and Scientific
Department of the Georgian Nutrition Association

2. Dietary Importance of Fats
Fats are a concentrated fuel source for the human energy
system. A large amount of energy can be stored in a relatively
small space within adipose tissue as compared with
carbohydrates that are stored as glycogen. As such, fats
supplement carbohydrates (the primary fuel) as an additional
energy source. In food, fats may be in the form of either solid
fat or liquid oil.

3. Georgian cuisine

4. What are Fats
Fats, are organic compounds that are necessary
for good health. The overall name of the
chemical group of fats and fat-related
compounds is lipids, which comes from the
Greek word lipos, meaning “fat.” The word lipid
appears in com-bination words that are used for
fat-related health conditions. For example, an
elevated level of blood fat is called
hyperlipidemia.

5. What are Fats
Lipids differ in many ways from the other
macronutrients –carbohydrates and proteins-
despite the fact that they contain the same
three elements, carbon, hydrogen and oxygen.
In addition to the different chemical structure,
lipids are not water soluble. Lipids are classified
according to chemical structure into three
categories: triglycerides, phospholipids, and
sterols. Each plays different roles, yet all are
necessary for body to function properly.

6. Triglycerides
Fats acids are carbon chains with an oxygen-containing
carboxyl group at the glycerol and a hydrogen-containing
methyl group at the terminal end. Fatty acids come in
several forms based on chain length and saturation. The
number of carbons atoms determines the length of the
fatty acids chain, whereas the degree of saturation refers
to the number of double and single bonds between the
carbon molecules . Fatty acids can be termed
unsaturated if there are double bonds on the carbon
chain or saturated if no double bonds exist. In nature,
most triglycerides exist with a mixture of fatty acids, both
saturated and unsaturated, though some have more of
one type than another in the mixture.

7. Unsaturated FATS
include both monounsaturated and polyunsaturated fats.
Unsaturated fats have a least one double bond on the
carbon chain. These fat tend to be liquid at room
temperature because this configuration lowers the
melting point of the fat compared to fats with no double
bonds. Unsaturated fats are classified according to the
length of the carbon chain and the placement of the first
double bond between carbons from the terminal, or
omega, end of the chain. Monounsaturated fats have
only one double bond on the carbon chain. The most
common dietary monounsaturated fat is calls oleic acids,
containing 18 carbons.

8. Health effects of oleic acids
Oleic acid is a common monounsaturated fat in human
diet. Monounsaturated fat consumption has been
associated with decreased low-density lipoprotein
(LDL) cholesterol, and possibly with increased high-
density lipoprotein (HDL) cholesterol, Oleic acid may be
responsible for the hypotensive (blood pressure
reducing) effects of olive oil that is considered a health
benefit.

9. Unsaturated FATS
As denoted by the name, polyunsaturated fats
have more than one double bond. Two
classifications of polyunsaturated fats are
omega-3 and omega-6 fatty acids. The first
double bonds on these carbon chains are at the
third carbon and sixth carbon, respectively, from
the omega end of the fatty acids. Two
polyunsaturated fats, linolenic acids and linoleic
acids are considered essential fatty acids.

10. Unsaturated FATS
Essential fatty acids play a role in maintaining healthy
skin and promoting normal growth in children. Essential
fatty acids make up part of our cell membranes and are
involved in blood clotting and inflammation. Even though
the body cannot make essential fatty acids, deficiency is
rare due to the abundance in the food supply. Deficiency
of essential fatty acids occurs when intake of fat is too
low or because of fat malabsorption, such as with cystic
fibrosis or inflammatory bowel disease.
Premature infants are at risk for essential fatty acids
deficiency because of borderline stores of these fats at
birth coupled with high-energy needs.

11. Saturated Fats and Trans Fats
Trans fats are a type of fatty acid that behave like
saturated fats in the body yet are not a fully
saturated fat. A process called hydrogenation-a
chemical process by which hydrogens are added to
an unsaturated fat, thereby making it more saturated
–creates a trans-fatty cid. Trans mean the hydrogen
atoms are cross the carbon chain from one another,
instead of the cis formation generally found in fats

12. Saturated Fats and Trans Fats
Saturated fatty acids have no double bonds on
the carbon chain and, therefore, each carbon is
attached to the maximum number of hydrogen
atoms. This structure gives the fatty acid more of
a straight-line configuration than is seen with
unsaturated fats and results in fats that are
usually hard at room temperature. Exceptions are
coconut and palm oils.

13. Palm oil
is made from the fruit of the oil palm. And the
oil obtained from the seeds of this palm tree is
called palm kernel oil. Palm oil has been used in
Russia relatively recently. It is ideal for baked
goods as well as confectionery products,
especially those intended for long-term storage.
Currently, palm oil is widespread, the benefits
and harms of which are still being studied, and
controversy around it does not subside.

14. Phospholipids
Like triglycerides, phospholipids have a backbone of
glycerol, but instead of having three fatty acids
attached, they have only two. Instead of the third
fatty acid, phospholipids have a phosphate group.
To being an important part of the food supply,
phospholipids are vital to our bodies. They
constitute cell membranes and allow bodily fluids
to exist in both fat-and water-soluble enviroments,
Lecithin is the most common phospholipid in the
body and is found in cell membranes and
surrounding nerve fibers.

15. Sterols
Sterols are the third class of lipids and are
composed of large, interconnected rings of
carbon. Sterols are synthesized by the body
and not required in the diet. Cholesterol is
most well-known sterol, whereas vitamin D,
testosterone, and estrogen are other familiar
examples. Although plant and animal foods
contain sterols, only foods that come from an
animal contain cholesterol

16. Functions of Fats in the body
• Transports fat-soluble vitamins A,D, E and K
• Cushions and protects organs
• Insulated body to maintain core temperature
• Provides lubrication
• Source of stored energy
• Component of cell membranes
• Component of myelin in the nervous system
• Building block for synthesis of other lipid-based
compounds, such hormones, vitamin D,
prostaglandins, and bile

17. Fat recommendations
• Consume less than 10 percent of calories from saturated
fatty acids and less than 300 mg/day of cholesterol, and
keep trans-fatty acids consumption as low as possible
• Keep total fat intake between 20% and 35% of calories,
with most fats coming from sources of polyunsaturated
fatty acids such as fish, nuts and vegetables oils
• When selecting and preparing meat, poultry, dry beans and
milk or milk products, make choices that are lean, low fat or
fat free.
• Limit intake of fats and oils in saturated and/or trans-fatty
acids, and choose products low in such fats and oils

18. Wellness Concerns
Fat is often implicated when talking about disease
progression and prevention, most commonly when
discussing risk of heart disease and cancer. Research
supports the role that too much fat can play in some
disease processes but is less clear with others.
Additionally, higher intake of same fats is being
recommended for some medical conditions, such as
omega-3 fatty acids used too treat high blood
triglyceride levels.

19. Obesity
Regarding of the type of fat, high-fat are
generally high in calories and can increase the
risk for obesity. Obesity occurs as a result of any
combinations of excess energy intake and
decreased energy expenditure. Excess energy
intake can occur with excess intake of any
macronutrient, carbohydrate, protein, or fat.

20. Obesity
High–fat foods are often to blame for excess
calories intake because they are generally more
calorically dense than high-carbohydrate or
protein foods, making it easier to consume extra
calories in serving. When working with an
individual who is seeking weight management
advise, the nurse can strategize with the client
about sources of excess calories in the diet from
high-fat foods and suggest lower-fat, lower-
calorie alternativies.

21. Cardiovascular Disease (CVD)
CVD is the general term that describes all diseases of the heart
and blood vessels. The cholesterol levels in our blood can
promote or serve as protection against cardiovascular disease.
Blood cholesterol level has several components that can be
influenced by diet, specifically the amount and types of fat
eaten. Blood cholesterol is comprised of several components,
including LDL (“bad” cholesterol” and HDL (“good” cholesterol).

22. Dietary omega-3 fatty acids
Dietary omega-3 fatty acids are recommended
for two distinct purposes in those with lipid
disorders and CVD. First increased intake of
omega-3 fats in supplemental form is part of the
treatment of high blood triglyceride level, a risk
factor for CVD. Second, intake of omega-3 fats is
associated with a decreased risk of CVD and
sudden death.

23. Cancer
Although concern exists that high intake of fat is
associated with increased risk of some cancers,
research results have been inconsistent.
Research has encompassed all types of fats,
including trans fats and omega-6 and omega-3
fats with varying results. Obesity, which often
accompanies a higher-fat diet, has a positive
association with prostate cancer risk, as does
saturated fat intake. A low-fat diet may reduce
the incidence of ovarian cancer among
postmenopausal women

24. Inflammatory Diseases and Other Conditions
Many conditions and diseases in the body are caused
by an inflammatory response. Rheumatoid arthritis
and inflammatory bowel disease are examples.
Omega-3 fats are often touted in the popular press
for the ability to treat these conditions, but the
amount of scientific evidence on this subject varies.
The effect of omega-3 fats on neurological and
cognitive conditions also been the subject of
research. Mood disorders, such as depression, and
attention-deficit hyperactivity disorder are examples.

25. Fish intake in at risk population
The cardiovascular benefits of omega-3 fats from
fish and fish oil sources are well recognized. As a
result the American Heart Association has made
recommendations for consuming two servings of
fish per week. However, contamination of some fish
with methylmercury is cause for concern, especially
in children and pregnant females, because of he
negative effects on development of the brain and
nervous system. Mercury levels vary among fish
species depending on environmental exposure to
pollutants and place on the food chain

26. Dietary Guidelines for Americans
• Consume less than 10% of calories from saturated fatty acids
by replacing them with monounsaturated and
polyunsaturated fatty acids.
• Consume less than 300mg/day of cholesterol.
• Keep trans-fatty acid consumption as low as possible by
limiting foods that contain synthetic sources of trans fats (e.g.,
partially hydrogenated oils) and by limiting other solid fats.
• Reduce the intake of calories from solid fats.
• Choose fat-free or low-fat milk and milk products.
• Replace protein foods that are higher in solid fats with choices
that are lower in solid fats and calories and/or are sources of
oils.
• Use oils to replace solid fats where possible

27. Digestion of some fats
can begin in the mouth where lingual lipase breaks down
some short chain lipids into diglycerides. However fats are
mainly digested in the small intestine. The presence of fat in
the small intestine produces hormones that stimulate the
release of pancreatic lipase from the pancreas and bile from
the liver which helps in the emulsification of fats for
absorption of fatty acids. Complete digestion of one
molecule of fat (a triglyceride) results a mixture of fatty
acids, mono- and diglycerides, as well as some undigested
triglycerides, but no free glycerol molecules.

28. Digestion of some fats