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The quantity and quality of fat in the diet play a critical role in
maintaining human health. Several studies in literature have
directly implicated the amount and type of fat intake to specific
diseases such as cardiovascular disease, hypercholesterolemia,
cancer, high blood pressure and obesity. The largest contributor to
this is TRANS FAT.
Fats and Oils as Nutrients
Countless reports concerning the negative effects of fats and oil
consumption have shifted today’s dietary focus towards fat
minimization. This is unfortunate, any student of nutrition knows
that fats are essential dietary components. Except for trans fat
which should be avoided as much as possible, other fats are
essential nutrients in our balanced diet. Excessive fat intake is
detrimental but the recent success of some diet programs such as the
Atkins Diet has shown a reduction of carbohydrates and
quality/quantity of fat and can have a positive effect on weight
loss and general health.
The functional role of fat in the diet is at least threefold. First,
fat provides calorie density to the diet. One gram of fat gives 9
Kcal of energy. Carbohydrates and proteins, provides only 4 Kcal of
energy per gram. Hence fat provides calorie density to the diet.
Secondly, fats are essential in the diet for the absorption and
mobilization of fat-soluble vitamins such as vitamin A, E, & K
and fat-soluble antioxidants. These vitamins are not utilized by the
body, if fat is not available in the diet. Thus fat is a vehicle
carrying the fat-soluble vitamins, nutrients and antioxidants in the
body. Thirdly, vegetable oils are the only sources of essential
fatty acids to the body.
Essential fatty acids (EFA) are those fatty acids, which the body
cannot synthesize and need to be supplied through diet. EFA’s
are the precursors for a group of chemically related compounds,
known as prostaglandins that are synthesized in the body from EFA.
If EFA is not supplied through diet to the body, the body cannot
synthesize prostaglandins. Prostaglandins play a key role in
regulating many physiological processes in the body, such as
controlling blood pressure, vascular damage in the brain and the
heart, preventing blood clot in the arteries, lowering cholesterol,
uterine contractions during child birth and menstrual cycles,
inflammation and other conditions. Fourthly, fat in the diet imparts
certain textural qualities, taste and palatability to the food. Fats
and oils are integral lubricants of foods in two ways: through use
as release agents as a part of the cooking process and as a
lubricant during mastication (chewing). Fats and oils modify flavor
release and improve palatability.
Functionality of Dietary Fats
The type of fat used impacts all the functional factors. Fat
molecules consist of three fatty acids linked to a glycerol
backbone, resulting in triglycerides. The fatty acids consist of
varying carbon chains ranging from 12 carbon atoms to 18 carbon
atoms, and with unsaturation ranging from 0 to 3 double bonds. These
triglycerides are termed as fat or oil. Depending on the nature of
fatty acids, the fat can be a solid fat or liquid fat at room
temperature. The solid fat will have more percentage of saturated
fats in the triglycerides and the liquid fats will have more
unsaturated fats. The term important to stability and health relate
to the degree of saturated and unsaturated fatty acids present in
oil or fat.
Saturated fatty acids (SFA) have no double bonds between carbon and
hydrogen; unsaturated fatty acids are those, which have one, two or
three double bonds between the carbon and hydrogen in the chain.
When there is one double bond it is termed monounsaturated fatty
acids (MUFA). More than one double bond is termed polyunsaturated
fatty acids (PUFA). A Trans Fat is when unsaturated fat bonds have
been deformed to resemble a saturated fat. Your body doesn't know
how to process trans fat and it disrupts all your metabolic
processes.
When a fat is rich in SFA, it is solid at room temperature, such as
coconut and palm oil and when it is rich in MUFA and PUFA it is
liquid at room temperature. All solid fats tend to increase
cholesterol and liquid fats tend to favor cholesterol reduction.
Fat Requirements
Fat consumption primarily occurs through salad and cooking oils,
followed by frying fats and bakery shortenings. Now let us look into
the quality and quantity of fat required in a balanced diet.
According to the American Heart Association (AHA) the optimum intake
of fat for an adult is 30% of the total caloric intake, to come from
fat. It means an adult ingesting 2000 calories of diet should be
getting 600 calories (30%) or 60-65 grams of fat per day. This
quantity of fat per day is required in a balanced diet to maintain
good health.
Coming to the quality of fat, the 30% of fat should include, not
more than 8-10% Saturated fat (SFA), 10-12% Monounsaturated fat
(MUFA) and not more than 10% of Polyunsaturated fat (PUFA). Among
the 10% PUFA at least 3% should come from n-3 fatty acids (Omega 3),
which are part of the PUFA family and as 0% Trans Fat or as little
as possible. Thus the quality and quantity of fat requirements to
the body is well defined.
Rice Bran Oil (RBO)
Rice bran oil is popular in several countries such as Australia, New
Zealand, Japan, India, Korea and China as cooking oil. It has been
shown that RBO is an excellent cooking and salad oil due to its high
smoke point and for its delicate flavor. RBO research shows it may
reduce cholesterol and cardiovascular diseases. The nutritional
qualities and health effects of rice bran oil are discussed below,
and are compared with other commonly used coking oils.
Nutritional Qualities of Rice Bran Oil (RBO)
Fats and oils act as a heat transfer medium, but also become a
component of the food. Because of this dual function, the oil must
meet a number of requirements. It must have good thermal and
oxidative stability. It must also have good flavor, good shelf life
and acceptable cost. Finally, it must have consumer appeal.
There are two types of fats we consume in our daily diets. One is
invisible fat, which comes from all natural fat present in
vegetables, fruits, cereals, poultry, meat, fish and other foods.
The other one is visible fat, which is the cooking medium, salad
oils and other added sources of oils. We have little control over
the invisible fat intake. However, the quantity and quality of
visible fat intake can be controlled to maintain better health.
Comparing known vegetable oils and rice bran oil to the fatty acid
profile recommended by the American Heart Association, we find RBO
is the closest to the AHA recommendations. AHA recommendations are
that SFA in the diet above 10% is not good, as it tends to raise the
cholesterol levels. SFA below this 10% level is good for health.
MUFA at 10% and above is good as it maintains cholesterol levels,
but below this level is not good for health. PUFA at the 10% level
is good, but too much of PUFA is known to generate free radicals and
aid carcinogenesis and hence is not good for health. PUFA below 10%
is not good, as the body needs essential fatty acids for its
metabolism.
Another component of fats and oils is the unsaponifiable fraction
(unsap), which contains the antioxidants and micronutrients of the
oil. RBO has 4.2% of unsap, whereas all other oils have unsap less
than 1-2%. It is the combination of an excellent essential fatty
acid profile and a high unsaponifiable fraction that brings about
possible cholesterol reduction. In addition to this RBO does not
produce any allergenic reactions when ingested, as does several
oils. RBO may have the highest cholesterol reduction capacity of any
other oil.
RBO unsaponifiable fraction is rich in vitamin E complex,
tocopherols and tocotrienols, a unique antioxidant known as gamma
oryzanol, high quantities of phytosterols, polyphenols and squalene.
RBO has a very good shelf life compared to other cooking oils
because of these antioxidants. These compounds are nutritionally
very valuable and it has been shown to be responsible for the
hypocholesterolemic effect. RBO appears to be the richest source of
tocopherols and tocotrienols. Hence RBO not only has a good fatty
acid profile, but also is a rich source of antioxidants and
micronutrients.
Hypocholesterolemic Effect of RBO
Studies have shown that GMO Free RBO in the diet may reduce LDL
cholesterol and triglycerides; it may increase HDL cholesterol (good
cholesterol), inhibits platelet aggregation and may help prevent
cardiovascular diseases. Clinical studies from Japan, India and the
U.S.A. have confirmed such results and named RBO as ”Health
Oil”. In every 1% reduction in cholesterol, there was a 2%
decrease in the risk of coronary heart disease. Thus RBO in the diet
may significantly reduce cholesterol without any side effects known
to exist with pharmaceutical drugs and is a healthy oil for human
consumption.
Safety of RBO
A safety evaluation of RBO was carried out by the FDA/WHO protocol.
It was proved to be safe for human consumption, without any side
effects. RBO has earned GRAS status in the U.S.A.
Taste and Acceptability
Foods were prepared in several ways, such as deep fried, pan fried,
baked foods and salad dressings in rice bran oil. Similar foods in
peanut oil, palm oil, soybean oil, olive oil and corn oil were
prepared and compared. Taste panel, color, appearance, smell and
texture were the criteria for the acceptability of the products. Our
GMO Free RBO prepared foods scored highest in all the panels, also
rated highest shelf life when compared to the other products. Our
GMO Free RBO was found to be more economical as less oil is absorbed
in the food, almost 20% less when compared to other oils. This lower
absorption rate is related to the viscosity of RBO, a physical
quality of the oil, which makes it light and non-sticky. The high
smoke point prevents the isomerization and polymerization of the
fatty acids and also the generation of free radicals at high
temperatures. There are many beneficial aspects of RBO that attracts
consumers to utilize RBO in their diet.
Check product ingredients for genetically modified and hydrogenated
oils that contain Trans Fats. Ask restaurants what they are using to
fry or prepare your meal. It makes a difference and your good health
depends on it.
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