- Why do we need fat in our diet? -
- Providing needed energy.
- Preventing essential fatty acid deficiency.
- Absorption of the fat-soluble vitamins A, S, E, K, and prevention of deficiencies of these vitamins.
- Flavor and texture to help prevent food from being bland and dry.
- Helping food to stay in the stomach longer, giving a greater sense of satisfaction and preventing hunger soon after meals.
- Production of endorphins (natural substances in the brain that produce pleasurable feelings).
- Diets containing less than 20 - 25% fat may trigger cravings.
- What does it do for our body? -
- Provides back-up energy if blood sugar supplies run out.
- Provides insulation under the skin from the cold and the heat.
- Protects organs and bones from shock and provides support for organs.
- Surrounds and insulates nerve fibers to help transmit nerve impulses.
- Forms part of every cell membrane in the body. It helps transport nutrients and metabolites across cell membranes.
- Makes a variety of other building blocks needed for everything from hormones to immune function.
- What happens when we don't have enough fat in our diet? -
- Dry, scaly skin
- Hair loss
- Low body weight
- Cold intolerance
- Poor growth
- Lower resistance to infection
- Poor wound healing
- Loss of menstruation
- Essential Fatty Acids -
Linolenic and arachidonic can be made from linoleic acid in the body. These are found in vegetable oils. These are needed to:
- Strengthen cell membrane and capillary structure
- Combine with cholesterol to helps transport it in the blood
- Help with the metabolism of cholesterol, and lowers blood cholesterol
- Help to regulate blood clotting time
- Help with inflammatory responses
- Form prostaglandins which have a variety of roles such as contraction of smooth muscles and muscle tone, blood clotting, regulation of blood pressure and many other functions.
Symptoms of essential fatty acid deficiency:
- Dry dull hair
- Scaly skin
- Impaired wound healing
- Inadequate amounts can contribute to heart disease and possibly arthritis
Amount needed to prevent fatty acid deficiency:
- At least 2% - 5% of the calories in your diet should come from linoleic acid to prevent essential fatty acid deficiency. This is about 2 teaspoons per day of vegetable oils, especially canola, safflower, and soybean oil.
- Cholesterol -
An odorless, white, waxy, powdery substance with many functions in the body:
- Vital role in metabolism and for proper functioning of the brain and other organs.
- Needed to make all steroid hormones.
- The skin uses cholesterol to produce 7 - dehydrocholesterol under sunlight which is turned into Vitamin D.
- Needed to form bile acids. Bile acids help fat in the diet to be digested and absorbed into the body.
- Needed to form cell membranes, especially in the skin and intestines.
The body can produce it's own cholesterol in the liver.
- Lipoproteins -
Lipoproteins are the transport form of fat in the blood. They contain protein, triglycerides, cholesterol, fatty acids, phospholipids, fat soluble vitamins, steroid hormones and other compounds. The high the protein amount, the high the density. They are classified:
- VLDL (very low density lipoproteins)-carries triglycerides to the tissues for use.
- LDL (low density lipoproteins)-helps carry cholesterol into cells. High levels of this in the blood are associated with atherosclerosis and heart disease.
- HDL (high density lipoproteins)-this helps carry cholesterol away from tissues to the liver for removal from the body. High levels protect the body from heart disease.
- Dietary Guidelines -
- Total fat - no more than 30% of calories
- Saturated - no more than 10% of calories
- Cholesterol - 200 to 300 mg or less
Eating fish three times a week will provide a good quantity of omega-3 fatty acids.</p>
Excess body fat is produced when there is too much protein, carbohydrates and fats in the diet.
Overeating everything (not just fat) leads to excessive storage of fat.