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					Fat
Definition



Fats are organic compounds that are made up of carbon, hydrogen, and oxygen. They
are a source of energy in foods. Fats belong to a group of substances called lipids, and
come in liquid or solid form. All fats are combinations of saturated and unsaturated
fatty acids.


Overview & Functions

Fat is one of the 3 nutrients (along with protein and carbohydrates) that supply
calories to the body. Fat provides 9 calories per gram, more than twice the number
provided by carbohydrates or protein.
Fat is essential for the proper functioning of the body. Fats provide essential fatty
acids, which are not made by the body and must be obtained from food. The essential
fatty acids are linoleic and linolenic acid. They are important for controlling
inflammation, blood clotting, and brain
development.

Fat serves as the storage substance for the body's extra calories. It fills the fat cells
(adipose tissue) that help insulate the body. Fats are also an important energy source.
When the body has used up the calories from carbohydrates, which occurs after the
first 20 minutes of exercise, it begins to depend on the calories from fat.
Healthy skin and hair are maintained by fat. Fat helps the body absorb and move the
vitamins A, D, E, and K through the bloodstream.



Food Sources

SATURATED FATS
These are the biggest dietary cause of high LDL levels ("bad cholesterol"). When
looking at a food label, pay very close attention to the percentage of saturated fat and
avoid or limit any foods that are high. Saturated fat should be limited to 10% of
calories. Saturated fats are found in animal products such as butter, cheese, whole
milk, ice cream, cream, and fatty meats. They are also found in some vegetable oils --
coconut, palm, and palm kernel oils. (Note: Most other vegetable oils contain
unsaturated fat and are healthy.)


UNSATURATED FATS
Fats that help to lower blood cholesterol if used in place of saturated fats. However,
unsaturated fats have a lot of calories, so you still need to limit them. Most (but not
all) liquid vegetable oils are unsaturated. (The exceptions include coconut, palm, and
palm kernel oils.) There are two types of unsaturated fats:

       Monounsaturated fats: Examples include olive and canola oils.
       Polyunsaturated fats: Examples include fish, safflower, sunflower, corn, and
        soybean oils.

TRANS FATTY ACIDS
These fats form when vegetable oil hardens (a process called hydrogenation) and can
raise LDL levels. They can also lower HDL levels ("good cholesterol"). Trans fatty
acids are found in fried foods, commercial baked goods (donuts, cookies, crackers),
processed foods, and margarines.
HYDROGENATED AND PARTIALLY HYDROGENATED FATS
This refers to oils that have become hardened (such as hard butter and margarine).
Partially hydrogenated means the oils are only partly hardened. Foods made with
hydrogenated oils should be avoided because they contain high levels of trans fatty
acids, which are linked to heart disease. (Look at the ingredients in the food label.)


Recommendations

       Choose lean, protein-rich foods such as soy, fish, skinless chicken, very lean
        meat, and fat-free or 1% dairy products.
       Eat foods that are naturally low in fat such as whole grains, fruits, and
        vegetables.
       Get plenty of soluble fiber such as oats, bran, dry peas, beans, cereal, and rice.
       Limit fried foods, processed foods, and commercially prepared baked goods
        (donuts, cookies, crackers).
       Limit animal products such as egg yolks, cheeses, whole milk, cream, ice
        cream, and fatty meats (and large portions of meats).
       Look at food labels, especially the level of saturated fat. Avoid or limit foods
        high in saturated fat.
       Look on food labels for words like "hydrogenated" or "partially hydrogenated"
        -- these foods are loaded with bad fats and should be avoided.
       Liquid vegetable oil, soft margarine, and trans fatty acid-free margarine are
        preferable to butter, stick margarine, or shortening.


Children under age 2 should NOT be on a fat-restricted diet because cholesterol and
fat are thought to be important nutrients for brain development.
It is important to read the nutrition labels and be aware of the amount of different
types of fat contained in food. If you are 20, ask your health care provider about
checking your cholesterol levels.



Side Effects

Eating too much saturated fat is one of the major risk factors for heart disease. A diet
high in saturated fat causes a soft, waxy substance called cholesterol to build up in the
arteries. Too much fat also increases the risk of heart disease because of its high
calorie content, which increases the chance of becoming obese (another risk factor for
heart disease and some types of cancer).
 A large intake of polyunsaturated fat may increase the risk for some types of cancer.
Reducing daily fat intake is not a guarantee against developing cancer or heart
disease, but it does help reduce the risk factors.



                               Omega-3 fatty acids




                                                         Omega-3 fatty
acids are a form of polyunsaturated fat that the body derives from food.
   Omega-3s (and omega-6s) are known as essential fatty acids (EFAs)
   because they are important for good health. The body cannot make
  these fatty acids on its own so omega-3s must be obtained from food.
   These different types of acids can be obtained in foods such as cold-
   water fish including tuna, salmon, and mackerel. Other important
 omega 3 fatty acids are found in dark green leafy vegetables, flaxseed
                       oils, and certain vegetable oils.
   Omega-3 fatty acids have been found to be beneficial for the heart.
    Positive effects include anti-inflammatory and anti-blood clotting
actions, lowering cholesterol and triglyceride levels, and reducing blood
pressure. These fatty acids may also reduce the risks and symptoms for
    other disorders including diabetes, stroke, rheumatoid arthritis,
 asthma, inflammatory bowel disease, ulcerative colitis, some cancers,
                              and mental decline.

				
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Description: Definition Fats are organic compounds that are made up of carbon, hydrogen, and oxygen. They are a source of energy in foods. Fats belong to a group of substances called lipids, and come in liquid or solid form. All fats are combinations of saturated and unsaturated fatty acids.