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What
are fats and fatty acids?
Fats
are a group of chemical compounds that contain
fatty acids. Energy is stored in the body
mostly in the form of fat. Fat is also needed
in the diet to supply essential fatty acids
that are substances essential for growth
but not produced by the body itself. The
terms fat and fatty acids are frequently
used interchangeably.
What
are the main types of fatty acids?
There
are three main types of fatty acids: saturated,
monounsaturated and polyunsaturated.
All fatty acids are chains of carbon atoms
with hydrogen atoms attached to the carbon
atoms.
A
saturated fatty acid has the maximum
possible number of hydrogen atoms attached
to every carbon atom. It is therefore said
to be "saturated" with hydrogen atoms, and
all of the carbons are attached to each
other with single bonds.
In
some fatty acids, a pair of hydrogen atoms
in the middle of a chain is missing, creating
a gap that leaves two carbon atoms connected
by a double bond rather than a single bond.
Because the chain has fewer hydrogen atoms,
it is said to be "unsaturated." A fatty
acid with one double bond is called "monounsaturated"
because it has one gap. Fatty acids having
more than one gap are called "polyunsaturated."
The
fat in foods contains a mixture of saturated,
monounsaturated and polyunsaturated fatty
acids. In foods of animal origin, a large
proportion of fatty acids are saturated.
In contrast, in foods of plant origin and
some seafood, a large proportion of the
fatty acids are monounsaturated and polyunsaturated.
The structure of saturated and unsaturated
chemical bonds looks like the diagram below.
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Saturated Fat
(i.e., saturated fatty acid)
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Unsaturated Fat
(i.e., unsaturated fatty acid)
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Carbon-Carbon
Single Bond
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Carbon-Carbon
Double Bond
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Fatty
Acids Information
Where
are they found?
Saturated
fats
Saturated
fat is found mostly in foods from animals
and some plants.Saturated
fats are usually solid at room temperature.
Foods
from animals — These include
beef, beef fat, veal, lamb, pork, lard,
poultry fat, butter, cream, milk, cheeses
and other dairy products made from whole
milk. These foods also contain dietary cholesterol.
Foods
from plants — These include
coconut oil, palm oil and palm kernel oil
(often called tropical oils), and cocoa
butter.
Polyunsaturated
and monounsaturated fats
— Polyunsaturated and monounsaturated fats
are the two unsaturated fats. They're found
primarily in oils from plants.
Polyunsaturated
fats — These include safflower,
sesame and sunflower seeds, corn and soybeans,
many nuts and seeds, and their oils. These
fats are usually liquid at room temperature
and in the refrigerator.
Monounsaturated
fats — These include canola,
olive and peanut oils, and avocados. These
fats remain liquid at room temperature but
may start to solidify in the refrigerator.
Can
Bad Fats Be Good? Edinformatics takes
a look at Omega-7 (Palmitoleic Acid).
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