LIPIDS Dr. Thomas J. Montville

Functions Provide energy Serve as energy reserve Assist in transport and adsorption of fat-soluble vitamins Serve as source of essential fatty acids Insulate and protect organs Maintain cell walls and play role in making Vitamin D Dr. Thomas J. Montville

Good Things About Fats Concentrated energy source Stores energy for long term use (fat cells) Flavor carrier Heat Transfer - frying Imparts texture – plasticity, flakiness Mouthfeel – creamy, smooth Dr. Thomas J. Montville

Bad things about fats Saturated – solid, animal, leads to cholesterol Unsaturated Makes you fat Coronary disease Heart disease Cancer Dr. Thomas J. Montville

Nutritional Overview Food Sources Recommended Intake Oils, sauces, spreads, butter Meat, poultry, fish, eggs, nuts (fish oil for omega 3s) Milk, cheese, dairy Breads cereals and grains with added fats Recommended Intake Less than or equal to 30% of calories from total fat Less than or equal to 10% of calories from saturated fat No more than 300 mg cholesterol Dr. Thomas J. Montville

Nutritional Overview of Lipids Classification Triglycerides – 95% of dietary fat 1 glycerol + 3 fatty acids Fatty acids Short, medium, or long chains Saturated (no double bonds) Monounsaturated (one double bond) Polyunsaturated (> one double bond) Omega 3 Omega 6 Dr. Thomas J. Montville

Fat Structure Fatty acids are either saturated, monounsaturated (contain one C=C double bond) or polyunsaturated (contain two or more C=C double bonds) Saturated fatty acids stack closely and are more solid. Unsaturated fatty acids are more fluid. “Hydrogenating” unsaturated fatty acids makes them more rigid. Dr. Thomas J. Montville

Fat Structure 1 Saturated Fat – Primarily animal sources: meat, poultry, milk, butter, cheese, egg yolk, lard Plant Sources: chocolate, coconut, coconut oil, palm oil, vegetable shortening 3. Polyunsaturated Fat - Primarily plant sources: vegetable oils (corn, safflower, soybean, sunflower, canola, etc.), margarine (most), mayonnaise, certain nuts (almonds, filberts, pecans, walnuts) Animal Sources: fish Dr. Thomas J. Montville

Fat Structure 2. Monounsaturated Fat Sources: avocado, peanuts, peanut butter, olive/olive oil Dr. Thomas J. Montville

Steroids: Chemical Messengers Cholesterol Corticosteroids Immune system Metabolism Anabolic Steroids Muscle and bone synthesis Hormones Testosterone Estrogen Dr. Thomas J. Montville

Phospholipids Structure Amphipathic Cell Membrane Phosphate Diglyceride Amphipathic Hydrophilic head Hydrophobic tail Cell Membrane Lipid bilayer Dr. Thomas J. Montville