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Forms of Fats
In this section, we'd like to demonstrate that not all fats were created equal.
Specifically, we'll briefly discuss:
1. Fat Structure - Fatty Acid Chains and TGs
2. MCTs - Medium Chain Triglycerides
3. Olive Oil - Monounsaturated Fatty Acids
4. CLA - Polyunsaturated Fatty Acids
5. Fish Oil - Omega 3 Polyunsaturated Fatty Acids
As discussed, there are three different types of fatty acids; saturated (coming
from animal fats), monounsaturated (coming from olive oil and avocados), and
polyunsaturated (coming from flax oil, hemp oil, fish oil, canola oil, safflower
oil, etc). Dietary fat, rather than simply floating around as free fatty acids,
typically is packaged up in the form of a triglyceride. Basically, a triglyceride
consists of 3 fatty acids (usually all of the same type) bound together by a
glycerol backbone. Essentially, the glycerol backbone has 3 carbons and a fatty
acid is attached (via a dehydration/synthesis reaction) to each of the 3 carbons.
Based on this structural phenomenon, scientists have recently begun exploring
an interesting development in fat science. They've begun making "structured
lipids." In essence what they're doing is making diacylglyerols (2 of the
carbons have fatty acids attached while 1 does not) and special triacylglycerols
(where there are fats of different lengths and properties attached to each carbon).
In clinical studies, these structured lipids have been shown to increase protein
synthesis in patients suffering from wasting. In addition, these fats are easily
oxidized (like the long chain fatty acids in fish oil) which leads to a thermogenic
response rather than a storage response. As a result these structured lipids
are now being heavily studied. While they're not on shelves yet, we wouldn't
be surprised if these structured lipids become food additives in the near future.
MCT's and CLA, probably due to their early introduction to the weightlifting
scene and the huge media hype associated with this introduction, have gotten
a bad reputation. These fats may, in fact, assist in weight loss.
MCT's, due to their medium chain length, are easily oxidized by skeletal muscle.
This is due to the fact that MCT's are quickly and easily transported to the
fat furnace, the mitochondrion. As a result, research (Hill et al 1989) has
demonstrated that TEF (thermogenic effect) with MCTs is double that of other
fats, making it comparable to protein in this regard.
CLA has remained a relative mystery to the research community. This is probably
due to the various forms (isomers) of CLA. Regardless, some research (Blankson
et al 2000) has shown that 12 weeks of CLA supplementation (at doses above 3.4g/day)
can increase LBM and decrease fat mass vs. olive oil. While the olive oil group
gained 1.5 lbs of fat and no lean body mass, the CLA group lost 4.5 lbs of fat
and gained 3 lbs of LBM.
Speaking of olive oil, even this "good fat" is better than saturated
fat for body composition. In a study comparing safflower oil, beef fat, palm
fat, and olive oil, it was shown that olive oil leads to a 14% higher oxygen
consumption rate than the other fats.
Finally, most research has shown that the favorite fats for humans are those
in fish oil. Delarue et al (1996) showed that fish oil supplementation (6g/day
added to the diet) dramatically changed the metabolism of fats and carbohydrates.
During an OGTT (oral glucose tolerance test - drinking a big 75g whack of liquid
sugar and measuring the subjects for 2 hours afterward), the fish oil group
burned 27g of fat vs. 20g in the placebo group. The fish oil group also burned
28g or carbs while storing 36g and the placebo group burned 51g of carbs while
storing only 14g.
In addition, baseline insulin was 30% lower in fish oil group and insulin responses
to OGTT were 50% lower in the fish oil group. What this tells us is that fish
oil allows the body to burn more fat and store more muscle glycogen, repartitioning
fuel away from fat cells toward muscle cells.
Since fish oils are polyunsaturated fats, it's important to not only increase
fish-oil intake, it's important to shift the ratio of polyunsaturated fat to
saturated fat (P/S). Van Marken, Lichtenbelt et al (1997) showed that the polyunsaturated
fat to saturated fat ratio is important to metabolic rate. A higher ratio of
P/S leads to metabolic increases (22% increase in TEF and 3% increase in daily
RMR).
So, if there's one thing you need to take from this section is that with all
else being equal, the fat composition (not just total intake) of your diet is
very important to your body composition. Saturated fats, while necessary to
a small extent, should only make up a small part of your diet while other fats
like olive oil, fish oil, flax oil, MCTs, and CLA all have a place on your plate.
This way you can get the same amount of daily energy from fats while gaining
lean mass and without gaining body fat.
Processed Oils are Bad Fats
Modern processing changes the chemical structure of fatty acids in such a way
that the human body cannot use them, they are therefore biologically inert and
are simply stored. The very worst type of fat is of course hydrogenated vegetable
oils. These are crucially damaged and processed fats that humans have mutated
in the production of their food chain. Hydrogenated vegetable fats are dangerous
to your health as well as being totally useless and unusable for the human body
- leading to the accumulation of fat stores and adipose tissue.
Nutritionally important fats have a structure known as a cis chemical configuration,
which means that hydrogen atoms on the carbons are all on the same side of the
molecule. Because of the slight electrical charge all of the hydrogen atoms
repel each other and put bends in the carbon chain, these bends are the essential
shape of the molecule that make it possible for all the special biological functions
of fats to take place.
Modern processing totally destroys this cis formation converting fats into
what is known as a trans formation. This basically describes where all the hydrogen
atoms lie on opposite sides of the fat molecule causing it to lose its bends
and straighten out. Such fat molecules lose their ability to perform important
biological functions. They are essentially unusable by the human body and cause
nothing but fat storage and build-up, while being potentially very harmful.
Nearly every food manufactured and processed and changed, that is not grown
or organically produced, free from manipulation, contain these lethal and damaged
fats and trans-fatty acids.
Hard Fats and Saturated Fatty Acids
These are straight chains with no kinks, no double bonds, and are slow to react
with other chemicals and carry no electrical charges.
Saturated fatty acids decrease oxygen supply to our tissues by making red blood
cells stick together, less mobile and less able to deliver oxygen to our cells.
Hard fats are things like butter, lard, and the solid fats on meats. Saturated
fats, are as stated, saturated with hydrogen atoms and so are basically useless
for bodily and brain function. These should generally be avoided where possible.
Hard Fats and Unsaturated Fatty Acids
These contain one or more double bonds between carbon atoms in their fatty carbon
chain and for each double bond they give up two hydrogen atoms.
The cis formation provides the fluidity needed in cell membranes.
Your body has the ability to change the long chain fats of more than 16 carbons
into unsaturated forms by inserting spaces called double bonds, therefore, it
can almost make all of the myriad of different fats it needs. However, there
are two essential fatty acids that your body cannot make itself. These are LINOLEIC
ACID and ALPHA LINOLENIC ACID. It is therefore essential that these fats are
provided by your diet. It is important to note that linoleic acid and alpha
linolenic acid are all the dietary fats an athlete needs. The best vegetable
source of linoleic and linolenic acids is flax or linseed oils, pumpkin seeds,
walnuts and soybeans. Not only are these fats essential but they are required
in certain quantities and ratios. The modern diet although deficient in both
of these highly essential fats, is weighted in the wrong ratios - a double whammy
of trouble. This has been linked to the potentially ever increasing degenerative
diseases throughout the modernised western world.
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