Transcript Fat and fatty acids

Lipids and Fatty Acids
pages 293, 294, 298, 299, 300
additional pages may be sited.
Functions of fat:
•Provide the body’s primary form of stored
energy
• make up cell membrane structure
• protects vital organs
• aids in the transmission of nerve impulses
• make things taste YUMMY
Lipids and Fatty Acids
• Lipids that are solid at room
temperature are referred to as fats
and lipids that are liquid at room
temperature are referred to as oils.
Simple Lipids
• Simple lipids are Dietary fats made up of
units called triglycerides (3 fatty acids held
together by a molecule of glycerol).
• Fat is digested in the stomach and the
intestines to smaller compounds. These
compounds are repacked into structures
called chylomicrons. These are transported
to the bloodstream where they are later
broken down by the liver.
Fatty Acids : page 298
Are named according to the position of the first double
bond. There are several families of fatty acids.
• Saturated: have no double bonds in the
primary hydrocarbon chain
• Monounsaturated: has one double bond
• Polyunsaturated: has more than one double
bond
• Saturated fatty acids are more common in
animal fat and less common in vegetable
oil.
• As saturation increases, fats become less
solid and more liquid at room temperature.
The length of the carbon chain
backbone is used to classify
fatty acids.
Short chain have 2 – 6 carbon
atoms
Medium chain have 8 – 12
carbon atoms
Long chain have greater than
14 – 24 carbon atoms.
Short chain are building blocks
Medium chain are found in mothers’
milk and certain foods such as coconuts.
They are thought to be more easily
broken down and absorbed
Long chain are the most common type
found in foods. More palatable than
medium chain.
Omega 3 and Omega 6
This refers to the area of the
“backbone” where the first double
bond is present.
The differences in structure result in
different effects within the body.
Omega 3 – alpha-linolenic acid
•Reduce inflammation
• cognitive function
• visual acuity
• reduces chances of CHF and
cancer
Symptoms of omega-3 fatty
acid deficiency include fatigue,
poor brain function, dry skin,
heart problems, mood swings
or depression, and poor
circulation.
Omega 6 - linoleic acid
converted to arachidonic acid in the dog.
AA found in animal tissue but not plant material,
which is why felines should not be fed a vegetarian
diet
•stimulate skin and hair growth
• maintain bone health
•regulate metabolism
•maintain the reproductive system.
•Primarily found in nuts and seeds
and vegetable oil
Omega 6 breaks
down into AA.
Omega 3
Arachidonic Acid:
Is the precursor to a group of fatty acids that
perform extensive hormonelike actions.
•vasoconstriction/vasodialation
• muscle contraction
• blood pressure homeostasis
• regulation of body temperature
• regulation of blood clotting
• control of inflammation
Fatty Acids
• Essential fatty acids play an important
role in kidney and reproductive
function, cell membrane formation,
and prostaglandin production.
• Signs of deficiency include: alopecia,
dull hair coat, anemia, and hepatic
lipidosis (fatty liver).
Fats – a
review
• Fats are derived from animal and vegetable fats. Just
as protein is composed of amino acids as their
building blocks, fats are composed of fatty acids as
their building blocks.
• 1 gram of fat = 9 calories of energy
• Fats provide more calories
• Fats make food taste better (palatable) and provide
better texture
• Fats are essential for the absorption of certain
vitamins, such as A, D, E and K
Fat Influences
• Appetite and food intake
• The dietary levels of minerals, vitamins,
and protein necessary to provide adequate
nutrition
• The ability to perform muscular work
• Hair coat condition
• Type of fat deposited in the body
• Tissue pathology
Technician Note
• Fats serve as primary sources of energy,
supply essential fatty acids, facilitate
digestion, and act as carriers for the fatsoluble vitamins (A, D, E, and K).
Fat Facts
• Fats are water insoluble
• Mammals cannot synthesize essential fatty
acids; therefore fatty acids must be obtained
from food.
• Fats, carbs and proteins are stored as fat
when fed in excess of requirement
• Fat is catabolized when the body needs
energy
Ketosis
• Primarily occurs in animals with diabetes mellitus. A
deficiency of insulin prevents the animal from utilizing
the glucose circulating in the blood stream. Insulin is
needed to get glucose to enter the body cells,
consequently the animal breaks down fat for energy.
Excessive amounts of acetyl-Coa (product A) starts to
accumulate in the blood. Accumulated product A is
converted to Ketone Bodies, large amounts of ketone
bodies cause a condition called ketosis. Ketosis is life
threatening because ketone bodies are acidic and the
body can not function when the blood drops below a
pH of 7.35.
National Exam note:
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Normal Animal = blood pH 7.4
If pH rises above 7.45 = alkalosis
If pH goes below 7.35 = acidosis
Normal range pH of blood: 7.35 – 7.45