The
Science of Fats All fats are composed of hydrogen,
carbon and oxygen atoms. Basically, an
atom is like a miniature sun, called the nucleus, which is made of protons and
neutrons. Orbiting around this miniature
son are electrons that are like the planets, always
staying in the same orbit/distance from the nucleus. There
may be more
than one electron in the same ring circling the nucleus. Everything on
earth and in the universe is made up of atoms. There are different
types of atoms, called elements, 90 of which occur in nature. The
number of protons in the nucleus of the atom determines which element it
is. Hydrogen, the smallest element has only 1 proton, carbon has 6
protons, and oxygen has 8 protons. Here is a 3-D picture of a carbon atom
with the blue representing electrons circling around the 6 protons and 6 neutrons
in the center: Oxygen has one ring with 2 electrons
available to bond to other elements and Hydrogen has one ring with one electron
circling around available to bond to other elements. Carbon has 4 bonds to connect with
other atoms to form a molecule, oxygen has 2, and hydrogen has one. Atoms
connect by sharing one or more electrons in their outer electron rings. In water (H20) you have an oxygen atom bonding to two hydrogen atoms - H-O-H. Saturated
Vs. Unsaturated The building blocks of all fats are
called fatty acids. Simply put, they're chains of carbon atoms
connected like beads on a string, with hydrogen atoms on each carbon atom and an
acid (carboxyl) group on one end. Two carbon atoms next to each other
can share either one or two bonds in fats. The type of
bond determines the number of hydrogen atoms each carbon atom can hold. The two
carbon atoms on the left, above, are held together by a single bond, and are said to
be 'saturated' because
they're holding all the hydrogen atoms they can. A saturated fat is saturated with
hydrogen atoms. The two
carbon atoms. above, on the right, are connected by a double bond (they are sharing two
electrons in their outer electron rings) are said to be 'unsaturated'
because each carbon atom could possibly hold on to one more hydrogen atom if the two carbon atoms weren't doubly bonded
to each other. So a carbon atom that is completely bonded to hydrogen atoms is completely saturated. Saturated
oils tend to be solid at room temperature because they pack closely
together. They tend to be stable and not bond with other atoms even when heated. Unsaturated fats tend to be liquid
at room temperature because the double carbon bonds tend to kink and keep the
molecules from packing tightly together. Unsaturated
is not necessarily better for you – as unsaturated fats are more unstable and
lead to oxidation and free radical damage. Many mono and poly unsaturated fats tend to
form carcinogens when heated at high temperatures, while saturated fats remain
stable and do not form carcinogens. Fatty Acids The building
blocks of all fats are called fatty acids. Fatty acids are chains
of carbon atoms connected like beads on a string, with hydrogen atoms attached to each
carbon carbon atom and an acid (carboxyl) group on one end of the chain of carbon atoms. A carboxyl
group consists of the following molecules hydrogen, oxygen, carbon, connected
to another oxygen: The number
of carbon atoms in each fatty acid chain, the type of bonds between the
carbons, and how many hydrogen atoms the carbon atoms are holding on to, all determine
the type of fat and its characteristics. Fatty acids with one double bonded pair of carbon atoms in
the chain are called monounsaturated. Fatty acids with two or more pairs of bonded carbon atoms are called polyunsaturated. Below is a
fat that is monosaturated because it has one pair of carbon atoms connected with a
double bond (so they are not saturated with hydrogen): Triglycerides Most fats in
are body and in foods are in the form of tryglyceride molecules – one glycerol
molecule with three fatty acids attached. Below is a Glycerol molecule, which consists of hydrogen, carbon and oxygen: The number of
carbon atoms in a fatty acid chain determines whether it is short, medium or long
chain:
Generally short and medium chain tryglycerides are more easily digested and used by the body. Omega
3, 6 and 9 Oils All Omega Fats, 3, 6, and 9 consist of
a carbon chain that has two ends – the acid end (COOH) that we saw examples of above and a methyl group end. A
methyl group is one carbon atom with 3 hydrogen atoms attached: Omega fats are unsaturated – the difference
between Omega 3, 6, and 9 is the position of the double carbon bond (C=C) from the methyl group end
of the chain:
These Omega oils may also have other
double bonds in their molecules. Below
is the chemical structure of linolenic acid, a common Omega 6 fatty acid found
in many vegetable oils (note that one double carbon bond is positioned 6 carbon
atoms away from the methyl group at the right end of the molecule): Omega 3 is considered “essential”
because the human body cannot manufacture it – it must be obtained from food. However humans have the ability to form the
long chain Omega 3 fatty acid EPA (20 carbon atom chain) andOmega 3 DHA (22 carbon atoms) from
the shorter chain Omega 3 8-carbon Alpha Linolenic Acid (ALA). The Omega 3 oils most critical to brain
function are DHA and DPA. To complicate
matters further, DHA is usually placed on the glycerol molecule in positions 1
and 3 in fish oil, while in humans can only use DHA whenit is placed in position
2. This means that after consuming fish
oil, the human body must rearrange the DHA into the Number 2 position to use it
and during this process, some percentage of the DHA is lost as this process is
not efficient. Omega 6 and 9 are non-essential
because the body can manufacture them.
Linolenic acid and Arachidonic acid are Omega 6 oils. Oleic acid (found in olive oil and other vegetable
oils) and erucic acid (found in canola oil) are examples of Omega 9 oils. Because Omega Fats are
unsaturated these oils must be used fresh and not allowed to oxidize (become
rancid) as they may form compounds that are detrimental to health and generate free radical damage. It is best to keep these oils sealed and
refrigerated once opened. Trans Fats Trans fat is the common
name for a family of artificially created unsaturated fats such as margarine
and shortening. These fats are
associated with increased risk of heart disease and stroke. Health authorities worldwide recommend
consumption of transfats be reduced to trace amounts. Unsaturated fats can
have different shapes or configurations depending on which side of the double
bond the hydrogens end up: In a 'cis'
(pronounced 'siss') formation, the hydrogens are on the same side. With 'trans'
formations, they're on opposite sides of the double bond. The linear stick and
letter figures I've been using don't really show the true shapes of the
cis/trans unsaturated fatty acids accurately. In actuality, as mentioned above,
there's a lot of bending going on whenever double bonds enter the scene. When vegetable oil processors thought it
would be cool to make their products stay solid at room temperature, like
butter and lard, they came up with a process called hydrogenation
which yielded margarine and shortening. Crisco is hydrogenated
cottonseed or soybean oil. Nobel Prize
winner Paul Sabatier (1854-1941) is considered the father of the hydrogenation
process. He discovered in 1897 that the metal, nickel, catalyzes, or
facilitates, the attachment of hydrogen to carbon compounds. In the actual process, workers heat the oil to very high
temperatures and bubble hydrogen gas through it in the presence of nickel or
some other catalytic metal. Since the vegetable oils are unsaturated, they can
take on a few more hydrogens. When they do, the molecule stiffens, and the fat
is now closer to a solid. They can control just how firm it gets by how long
they pump the gas through. That's why you'll sometimes see the term 'partially
hydrogenated' on ingredient labels. What also happens during hydrogenation, or later, during
high heat cooking with the processed oils, is the formation of molecules so
strangely configured that they're completely unsuitable for use in our bodies. In
addition, the double bonds in these foreign fatty acids are easily broken,
allowing the formation of free radicals- highly reactive molecules with an
unpaired electron, just looking for something to grab on to. Promotion of breast cancer, heart disease, diabetes,
weakened immune systems and hormonal dysfunction are just some of the maladies
for which studies have implicated these unnatural trans fats. What About Cholesterol? Cholesterol
is a waxy steroid of fat. Cholesterol is
essential for all animal life. It is an
essential structural component of mammalian cell membranes and is required to
establish proper membrane permeability and fluidity (critical to communication
between neurons). In addition it is an
important component for the manufacture of bile acids, steroid hormones and
Vitamin D. Animal fats
are complex mixtures of triglycerides with lesser amounts of phospholipids and
cholesterol. All animals fats and eggs
contain cholesterol, as does human breast milk. Having too
low levels of cholesterol can lead to neurodegenerative conditions such as
Parkinson’s and Alzheimer’s, depression, cancer, and stroke. Statin drugs that lower cholesterol also
increase risk of neurodegenerative conditions and congestive heart failure. Article provided by www.autismcoach.com |