Fat Functions

• store fuel to provide long lasting energy
• creates the lipid bi-layer of cell membranes
• cushions and protects our vital organs 
• provides the building blocks for hormone
• keeps us warm
• essential for proper brain and immune function
• keeps skin soft and velvety
• helps to maintain optimal weight

Essential Fatty Acid Functions

• prevent blood from becoming too thick, reducing clots
• relax blood vessels
• lowers blood pressure 
• help the body to maintain the proper water balance
• decrease pain and inflammation
• improve nerve function
• important for brain function, vision, learning ability, coordination and mood

Types of Fat:

Saturated Fat: saturated fat comes mainly from animal sources such as animal meats from beef, pork, lamb, poultry, and from dairy products and egg yolks.  Saturated fats are considered less desirable fats as they can contribute to heart disease by raising blood cholesterol levels.  Most health care providers recommend reducing the amount of saturated fat in the diet.

Saturated fats can be made up of short-, medium-, or long-chain fatty acids.  Short and medium-chain saturates do not clog arteries as do the long-chain saturates found in meat and dairy.  Coconut oil, although a saturated fat, contains short and medium-chain fatty acids and is therefore metabolized differently than the long-chain fatty acids found in meat.  Medium chain saturates (MCT’s) are not associated with increasing cholesterol.  MCT’s are more easily converted to energy (by the liver) than stored as fat.

Trans fatty acids: Trans fats come from hydrogenated or partially hydrogenated oils.  Hydrogenation is a process that converts liquid oil into a semi-solid or solid fat, making it shelf stable. Unfortunately, the process of hydrogenation forms trans fat.

Trans fats are found in a wide range of foods such as shortening, margarine, baked products, processed foods, pancake and baking mixes, peanut butter, breads and microwave popcorn just to name a few.  An easy way to avoid trans fat is to be sure that the ingredient list does not include “partially hydrogenated oil” of any kind.

Trans fats increase cholesterol and all blood lipids (triglycerides), inhibit EFA metabolism, modify cell membrane properties (cell walls become stiff and unable to process nutrients and wastes).  Some researchers believe that trans fats change how cells process insulin---which can lead to diabetes.  Trans fats have been linked to cancer.

Unsaturated Fat: There are two types of unsaturated fats, mono- and polyunsaturated.  The prefixes mono- and poly- refer to the number of double bonds in the carbon chain of the fat.  Unsaturated fats keep our cell membranes supple, allowing cells to get nutrients in and let waste products out.

Monounsaturated Fats: include canola oil, olive oil, avocado and sunflower oil.  Monounsaturated fats are at the center of the popular Mediterranean diet.  These types of fats help to regulate blood cholesterol and promote the proper functioning of the cardiovascular system.  Monounsaturated fats are more stable than polyunsaturated fats, so they can tolerate higher temperatures for cooking.

Polyunsaturated Fats: include the “essential fatty acids” known as Omega-3 and Omega-6 fatty acids. We have to get essential fatty acids from the food we eat, as we cannot manufacture them in our bodies. We become deficient if we don’t get enough EFA’s.  There are two types of polyunsaturated fats: omega-3 and omega-6.

Omega-3 Fatty Acids: Omega-3 fatty acids come from cold water fish, such as salmon, mackerel, herring, tuna, black cod, sardines and halibut.  They also come from flax, hemp and pumpkin seeds and their oils.  Optimal intake of Omega-3 fatty acids would include adding cold-water fish to your diet several times per week.  In addition, you can supplement your diet with fish, flax or hemp oil.

Sources of Omega-6 Fatty Acids: This family of fats comes exclusively from seeds and their oils.  The best are grapeseed, corn, walnut, and soybean oil.  The omega-6 fats, called gamma-linolenic acid (GLA), found in evening primrose and borage oil may be beneficial for skin conditions such as eczema and psoriasis.

Cholesterol: Despite its bad reputation, cholesterol is an important part of overall health.  It is when cholesterol becomes too high that dietary changes need to be made.  We need some cholesterol to give structure to cell walls, to produce hormones, and to vitamin D.  Dietary cholesterol comes from animal products only (plants do not make cholesterol): eggs, meat, dairy, shellfish, and organ meats are particularly high in cholesterol.

Fiber decreases excess cholesterol: Soluble fiber is very important for keeping cholesterol under control. Soluble fiber forms a gel and binds to bile and cholesterol in the digestive tract, inhibiting its absorption, and shuttles it out as waste.  Regular consumption of soluble fiber may help reduce LDL (bad) cholesterol levels over time.

Resources:
Essentials of Nutrition and Diet Therapy, 7th edition, by Sue Rodwell Williams, copyright 1999, Mosby, St. Louis
Understanding Nutrition, 5th edition, by Whitney, Hamilton, Rolfes, copyright 1990, West Publishing Co., St. Paul
The Optimum Nutrition Bible, by Patrick Holford, copyright 1999, The Crossing Press, Freedom, California
www.spectrumorganics.com