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An ideal food has six components such as carbohydrate, protein, fat, vitamin, salt and water. Every component is essential for our body for maintaining good health. Fat is necessary because it plays many critical roles in the body. It’s a very rich source of energy that sup-ports in cell function, helps insulate the body, protects us from injury, helps vitamin absorption and adds flavor and texture to foods. As well as fat also responsible for the risk of developing obesity, diabetes and heart disease in many cases. There are two classes of fat cate-gorized in our listed daily food items; one is good fat (unsaturated fat) reduce the risk of developing heart diseases by helping to reduce blood cholesterol another is bad fat (saturated fat) can rise blood cholesterol. A fat diet, low in unsaturated fatty acids and rich in saturated fatty acids is thought to be an imperative basis of atherosclerosis and cardiovascular diseases. For maintaining good health, every person should update his knowledge regarding his food habits. This review focuses on the studies to summarize the good fats and bad fats from our daily listed food intake.
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International Journal of Health, 2 (2) (2014) 41-44
International Journal of Health
Journal home page: www.sciencepubco.com/index.php/IJH
doi: 10.14419/ijh.v2i2.2903
Review Paper
A comparative overview on good fats and bad fats:
guide to control healthy body
Sujan Banik *, Mohammad Salim Hossain
Department of Pharmacy, Noakhali Science and Technology University, Sonapur, Noakhali-3814, Bangladesh
*Corresponding author E-mail: pharmasujan@yahoo.com
Abstract
An ideal food has six components such as carbohydrate, protein, fat, vitamin, salt and water. Every component is essential for our body
for maintaining good health. Fat is necessary because it plays many critical roles in the body. It’s a very rich source of energy that sup-
ports in cell function, helps insulate the body, protects us from injury, helps vitamin absorption and adds flavor and texture to foods. As
well as fat also responsible for the risk of developing obesity, diabetes and heart disease in many cases. There are two classes of fat cate-
gorized in our listed daily food items; one is good fat (unsaturated fat) reduce the risk of developing heart diseases by helping to reduce
blood cholesterol another is bad fat (saturated fat) can rise blood cholesterol. A fat diet, low in unsaturated fatty acids and rich in saturat-
ed fatty acids is thought to be an imperative basis of atherosclerosis and cardiovascular diseases. For maintaining good health, every
person should update his knowledge regarding his food habits. This review focuses on the studies to summarize the good fats and bad
fats from our daily listed food intake.
Keywords: Fat, Cholesterol, Saturated Fat, Trans Fat, Unsaturated Fat, Good Fat, Bad Fat.
1. Introduction
Fat is the most rigorous foundation of food energy. There are 9
calories in every gram of fats (Noakes, 2003). There are various
group of compounds of this type of diet those are basically soluble
in organic solvents and insoluble in water. Fat is defined chemi-
cally as triglycerides; trimesters of glycerol with several fatty
acids (Brouwer et al., 2010). On the basis of their structure and
composition fats may be both solid and liquid at room tempera-
ture. Several terms are frequently used to refer fats those are oils,
fats and lipid, in which oils such as vegetable oil, canola oil, olive
oil etc are liquids at normal room temperature, they are frequently
used to refer fats, on the other hand fats is typically used to refer
to fats that are solids at typical room temperature (e.g., lard, butter,
shortening etc). Lipid is another familiar term which is generally
worn to refer together liquid and solid fats, beside with other
linked substances, generally in a medical and biochemical context.
There are abundant diverse kinds of fats, but each is a distinction
on the identical chemical arrangement. More specifically, the en-
tire fats are sources of fatty acids and glycerol.
Cholesterol is a waxy like substance that is found in the fat cells of
our body and in the bloodstream. Its function akin to as a “protec-
tive barrier’ around the cells called a membrane. When the level of
cholesterol is too elevated in our body, it can cause risk factors for
other diseases to insist. There are largely two types of cholesterol;
one is HDL (high density lipoproteins) and another is LDL (low
density lipoproteins) cholesterol (Brouwer et al., 2010).
HDL cholesterol is also known as “good cholesterol” and LDL
cholesterol is considered to be “bad cholesterol”. Higher levels of
HDL protects against heart attack and stroke because it keeps LDL
cholesterol from building up around the heart. LDL cholesterol is
carried through the blood stream and to the heart. When too much
LDL cholesterol builds up, it causes blockages in the big tubes
(arteries) that carry blood to the heart. This damages the heart and
over time can lead to a heart attack or stroke.
2. Sources
The main sources of fats are food items such as meat, egg yolk,
milk, nuts, butter, ghee, cheese, different types of vegetables oils
etc.
3. Classification
3.1. Saturated fats
It has no double bonds in the hydrocarbon chain and is solids at
room temperature. Butter, ghee etc are familiar instance of satu-
rated fats. High intakes of saturated fats help to raise blood choles-
terol level (especially LDL cholesterol) that can guide to coronary
disorders and high blood pressure (Ravnskov, 1998). The people
who spend a sedentary daily life and old people have to reduce the
ingestion of saturated fats. On the other hand, the energy require-
ment is high for the people who involved in heavy labor; they
have to need fat intake more from their daily requirement.
3.2 Unsaturated fats
It has one or more double bonds and ‘kink’ in the hydrocarbon
chain and is liquid at room temperature. Oils are unsaturated fats.
Unsaturated fats may be monounsaturated fats, polyunsaturated
fats (more than one double bond). High intake of these types of
fats help to lower LDL (bad) cholesterol and help to raise HDL
42
International Journal of Health
(good) cholesterol. Olives, Olive oil, sunflower oil, peanut oils are
unsaturated fat.
Fig. 1: Saturated and Unsaturated Fats
Depending on the dietary necessities, fats are two kinds:
a) Essential fats: Essential fats are categorized those types of fats
that are not manufactured by the body such as linoleic acid,
linolenic acid, arachidonic acid etc and must be included in the
diet.
b) Non-essential fats: Those types of fats are synthesized by
means of body and are not indispensable in the diet identified
as non-essential fats. For instance: glycine.
4. Functions of fats
Fats are the principal energy supplies of the body, which form
a vital source of energy during hunger or other labor works.
Fats take part in an important role in the absorption of fats
soluble vitamins A, D, E and K.
Control cholesterol level, so act as an important regulating
compound.
Help to maintain healthy skin and hair
Acts like a “cushion” and heat regulator to protect your heart,
liver and other vital organs
5. Good fats, bad fats
Therefore, from this study we can suggest that, all types of fats are
not similar. Some of these are listed as essential for maintaining
good health (good fat) and others listed as dangerous for our body
(bad fat). The listed bad fats are responsible for increasing blood
cholesterol levels or have also other harmful sound effects on
cardiovascular health (Food Standard Board, 2007). After all,
ingestion of excess fats of all categories can add intemperance
calories and guide to weight gain. This review will help us to sort
out the “heart healthy” (good) fats from the “unhealthy” (bad) fats.
5.1. Heart healthy (good) fats
Unsaturated fats are categorized as good fats. These types of fats
are found chiefly in plant foods or in fish that eat tiny flora. Fur-
ther unsaturated fats are categorized into two groups’ monounsatu-
rated fatty acid (MUFA) and polyunsaturated fatty acid (PUFA).
The two polyunsaturated fatty acids crucial for physical condition
are omega-3 and omega-6. Omega-3 and omega-6 fatty are very
essential for body because they play various superior role in our
body but they cannot be synthesized by the body and be required
to come from food. The beneficial effects of omega-3 fatty acids
are brain and eye development of the growing fetus during preg-
nancy and for maintaining and promoting health all over life
(Hooper, 2004). Omega-6 fatty acids also take part in develop-
ment of brain and heart function and also in normal growth and
development (Harris et al., 2009). Both mono-and poly-
unsaturated fats may help to lower LDL (bad) cholesterol and
decrease risk of heart disease. Olive, canola and peanut oils are
high in monounsaturated fats, and safflower, sunflower, and corn
oils contain more polyunsaturated fats.
5.1.1. Omega-3 fatty acids
The common food sources of omega-3 fatty acids are fatty fish
such as salmon, herring, sardines, trout and flaxseed, walnuts as
well as canola oil. The American Heart Association (AHA) has
suggested that healthy adults eat at least two servings of fish per
week to boost omega-3 fatty acid intake (Lichtestein et al., 2006).
It has numerous potential health promoting benefits, such as:
Decrease inflammation in case of heart disease, inflammatory
bowel disease and rheumatoid arthritis.
Help prevent blood from clotting and sticking to artery walls.
Reduce risk for blocked blood vessels and heart attacks.
Prevent hardening of the arteries.
Lower risk of sudden death and abnormal heart rates.
Reduce triglyceride levels.
Lower blood pressure.
5.1.2. Omega-6 fatty acids
The common sources of omega-6 fatty acids are vegetable oils
such as corn oil, safflower oil, sesame oil, soybean oil, sunflower
oil; soft (liquid or tub) margarine, preferably one that is trans-fat-
free; walnuts; sunflower seeds, pumpkin seeds, sesame seeds; soy
“nuts” (roasted soy beans), soy nut butter and tofu etc.
Omega-6 fatty acids also play key roles in health promoting bene-
fits, for instance:
Neutral or reduce levels of inflammatory mediators.
Replacing saturated and trans fat with omega-6 fatty acids
linked with decreasing risk of heart disease.
Develop insulin resistance and decrease the occurrence of
diabetes
Inferior blood pressure.
Inferior cholesterol levels.
5.1.3. Monounsaturated fats
The available food sources of monounsaturated fats are vegetable
oils: olive oil, canola oil, peanut oil; nuts: almonds, cashews, pea-
nuts, pecans, pistachios; avocado; peanut butter and almond but-
ter.
The main functions of this lower LDL cholesterol, while increas-
ing HDL (good) cholesterol.
5.2. Unhealthy fats (bad fats)
Those types of fats shows unwanted effects in our body are known
as bad fats such as saturated fats and Trans fats (Uauy et al., 2009;
Jakobsen, 2008). Meats with high-fat and dairy foods such as
cheese, whole milk etc is the main foundation of saturated fatty
acid. The enlisted food items are the most important resource of
unhealthful fats and have to avoid or eaten scarcely.
5.2.1. Saturated fats
The familiar food sources of saturate fats are fatty cuts of beef,
pork and lamb; poultry skin, chicken wings, dark meat chicken;
high fat dairy products: cheese, butter, whole milk, 2% reduced fat
milk, cream, cream cheese, sour cream, ice cream; tropical oils:
coconut oil, palm oil, palm kernel oil, cocoa butter; lard and suet
etc.
5.2.2. Trans fatty acids (Tran’s fats)
Tran’s fats (occasionally called Trans fatty acids) are produced
during the progression of hydrogenation of vegetable oils
(Mozaffarin et al., 2006; Bakker et al., 1997). Hydrogenation is a
method used by food manufacturers to add hydrogen to vegetable
oils to create a solid fat. Tran’s fat is the worst kind of fat, even
worse than saturated fat. But when shopping for food, always
check labels and choose products with 0 grams of Tran’s fat.
International Journal of Health
43
Trans fat also known as partially hydrogenated oil. It’s called
hidden killer of our body.
Food Sources: There are two sources of Tran’s fat, one is natural
and another is manmade. The common sources of Tran’s fat such
as vegetable shortening and stick margarines; refrigerated dough
products; fried foods: doughnuts, French fries, other deep fried
fast food items; commercially ready foods containing partially
hydrogenated oils: crackers, cookies, cakes, pastries, microwave
popcorn and other snack foods.
High intake of saturated fats and Trans fats can raise the level of
bad cholesterol (LDL cholesterol) in our body. These fats may
also make the lining of blood vessels (the endothelium) less flexi-
ble. In adding together, Tran’s fats may demoralize the “good”
blood cholesterol (HDL cholesterol) level when eaten in large
quantities. Tran’s fats can have an effect on our health - especially
our heart health.
From the basis of ‘Good Fats’ and ‘Bad Fats’ we can classify fats
by the following ways: 3
Table 1: Guide to Control Healthy Body Choose the Food Items in This Order
Avoid
Trans Fat
Eat less
Saturated Fat
Eat
Good Fats
6. Daily restrictions for fat ingestion
According to the U.S. Department of Agriculture and the Depart-
ment of Health and Human Services (HHS) recommendation the
daily limit of fat intake should not more 35 percent of your daily
calories (Ward, 2010). This recommendation notice that, if any
person consume 1800 calories a day, then he/she have to eat no
more than 70 grams of fat daily (To calculate: 1,800 X 0.35 = 630
calories, 630/9 = 70 g total fat). This calculation is an upper limit
of fat intake and the majority of these fat calories appear from
monounsaturated and polyunsaturated sources. By the organiza-
tion of USDA and NHS at yet not established an upper limit for
tans fat, but they recommended that your trans-fat intake should
be low as possible. According to American Heart Association the
set value of upper limit of Trans fat intake not more than 1 percent
of your daily calories (Kaneshiro, 2009). Once you can choose a
product contrast nutrition facts labels that are lowest in saturated
fat, Trans fat and cholesterol. Always choose the product with the
lowest amount of saturated fat, 0 grams tans fat and with less cho-
lesterol (Mozaffarin et al., 2006).
7. Conclusion
There is a widespread false impression that all body fat is not
good. In reality, a number of body fats are essential to guard the
person’s health as well as supplying a pool of energy for perform-
ing a variety of body functions. To know better this thought, the
total weight of body fat can be further divided into three divide
categories:
Fats
Trans Fats
Saturated Fats
MUFA
PUFA
Omega-6
Omega-3
Bad Fats
Good Fats
44
International Journal of Health
The amount of body fat that is essential to keep the body from
any type of infectious diseases and to protect the internal or-
gan from bruising damage is known to be Essential Body Fat.
The amount of additional body fat that does not root of any
medical risks, and provides a pool of “fuel” for employ by the
body is known to be Reserve Body Fat.
Another is Excess Body Fat, which is above and over the grouping
of essential body fat together with reserve body fat. It causes the
menace of severe health problem such as strokes, heart attacks,
diabetes and certain forms of cancer.
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Trans fats, unsaturated fatty acids with at least one double bond in the trans configuration (Figure 1), are formed during the partial hydrogenation of vegetable oils, a process that converts vegetable oils into semisolid fats for use in margarines, commercial cooking, and manufacturing processes. From the perspective of the food industry, partially hydrogenated vegetable oils are attractive because of their long shelf life, their stability during deep-frying, and their semisolidity, which can be customized to enhance the palatability of baked goods and sweets
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Improving diet and lifestyle is a critical component of the American Heart Association's strategy for cardiovascular disease risk reduction in the general population. This document presents recommendations designed to meet this objective. Specific goals are to consume an overall healthy diet; aim for a healthy body weight; aim for recommended levels of low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, and triglycerides; aim for normal blood pressure; aim for a normal blood glucose level; be physically active; and avoid use of and exposure to tobacco products. The recommendations are to balance caloric intake and physical activity to achieve and maintain a healthy body weight; consume a diet rich in vegetables and fruits; choose whole-grain, high-fiber foods; consume fish, especially oily fish, at least twice a week; limit intake of saturated fat to <7% of energy, trans fat to <1% of energy, and cholesterol to <300 mg/day by choosing lean meats and vegetable alternatives, fat-free (skim) or low-fat (1% fat) dairy products and minimize intake of partially hydrogenated fats; minimize intake of beverages and foods with added sugars; choose and prepare foods with little or no salt; if you consume alcohol, do so in moderation; and when you eat food prepared outside of the home, follow these Diet and Lifestyle Recommendations. By adhering to these diet and lifestyle recommendations, Americans can substantially reduce their risk of developing cardiovascular disease, which remains the leading cause of morbidity and mortality in the United States.