Nutrition for Health and Health Care, 5th Edition DeBruyne ■ Pinna © Cengage Learning 2014 Lipids Chapter 4

Nutrition for Health and Health Care, 5th Edition DeBruyne ■ Pinna © Cengage Learning 2014 Introduction Fat –Dietary intake Health risks associated with too much and too little –Member of lipids class of compounds Triglycerides (fats and oils) Phospholipids Sterols

Nutrition for Health and Health Care, 5th Edition DeBruyne ■ Pinna © Cengage Learning 2014 Roles of Body Fat Lipids: provide energy Adipose tissue –Fat-storing cells; also secretes hormones –Fat stored in fat cells Supplies 60 percent of the body’s ongoing energy needs during rest –Fat embedded in muscle Along with glycogen, provides energy to muscle

Nutrition for Health and Health Care, 5th Edition DeBruyne ■ Pinna © Cengage Learning 2014

Nutrition for Health and Health Care, 5th Edition DeBruyne ■ Pinna © Cengage Learning 2014

Nutrition for Health and Health Care, 5th Edition DeBruyne ■ Pinna © Cengage Learning 2014 The Chemist’s View of Lipids Triglycerides –Predominant form of lipids –Three fatty acids attached to a glycerol “backbone” Fatty acids –Differ in chain length and degree of saturation –What is the difference between a saturated fatty acid and an unsaturated fatty acid?

Nutrition for Health and Health Care, 5th Edition DeBruyne ■ Pinna © Cengage Learning 2014

Nutrition for Health and Health Care, 5th Edition DeBruyne ■ Pinna © Cengage Learning 2014

Nutrition for Health and Health Care, 5th Edition DeBruyne ■ Pinna © Cengage Learning 2014 The Chemist’s View of Lipids (cont’d.) Comparison of three fats –Lard (from pork): most saturated ► hardest –Chicken fat: less saturated ► somewhat soft –Safflower oil: most unsaturated ► liquid Stability –Why are polyunsaturated fatty acids most susceptible to becoming rancid?

Nutrition for Health and Health Care, 5th Edition DeBruyne ■ Pinna © Cengage Learning 2014 The Chemist’s View of Lipids (cont’d.) Stability –Methods manufacturers protect fat-containing products from rancidity 1.Seal products airtight and refrigerate 2.Add antioxidants, e.g., BHA and BHT 3.Hydrogenate products

Nutrition for Health and Health Care, 5th Edition DeBruyne ■ Pinna © Cengage Learning 2014 The Chemist’s View of Lipids (cont’d.) Hydrogenation –Advantages: protects against oxidation and alters texture –What are the disadvantages? Essential fatty acids –Linoleic acid: omega-6 fatty acid –Linolenic acid: omega-3 fatty acid

Nutrition for Health and Health Care, 5th Edition DeBruyne ■ Pinna © Cengage Learning 2014

Nutrition for Health and Health Care, 5th Edition DeBruyne ■ Pinna © Cengage Learning 2014 The Chemist’s View of Lipids (cont’d.) Phospholipids: class of lipids –Food sources: eggs, soybeans, peanuts, etc. –Lecithin and other phospholipids Constituents of cell membranes Emulsifiers in the body Some generate signals in cells

Nutrition for Health and Health Care, 5th Edition DeBruyne ■ Pinna © Cengage Learning 2014

Nutrition for Health and Health Care, 5th Edition DeBruyne ■ Pinna © Cengage Learning 2014 The Chemist’s View of Lipids (cont’d.) Sterols –Large, complex molecules Interconnected rings of carbon Cholesterol, vitamin D, and sex hormones –Cholesterol Obtained in foods as well as made by the liver

Nutrition for Health and Health Care, 5th Edition DeBruyne ■ Pinna © Cengage Learning 2014 The Chemist’s View of Lipids (cont’d.) Cholesterol –Leaves liver by two routes: 1.Incorporated into bile, stored in the gallbladder, and delivered to the intestine 2.Via the bloodstream to all the body’s cells

Nutrition for Health and Health Care, 5th Edition DeBruyne ■ Pinna © Cengage Learning 2014 Digestion and Absorption of Lipids Goal of fat digestion –Break triglyceries into monoglycerides, fatty acids, and glycerol (Table 4-3)

Nutrition for Health and Health Care, 5th Edition DeBruyne ■ Pinna © Cengage Learning 2014 Health Effects and Recommended Intakes of Fats Diet high in saturated fats or trans fats –Increased risk of cardiovascular disease –Greater-than-average chances of some cancers –An increasing waistline often increases blood triglycerides

Nutrition for Health and Health Care, 5th Edition DeBruyne ■ Pinna © Cengage Learning 2014 Health Effects and Recommended Intakes of Fats (cont’d.) Fats and heart health –High LDL: increased likelihood of fatal heart attack or stroke Promotes cholesterol uptake in the blood vessel walls –High HDL: lower disease risk –Trans fats: raise LDL and lower HDL

Nutrition for Health and Health Care, 5th Edition DeBruyne ■ Pinna © Cengage Learning 2014

Nutrition for Health and Health Care, 5th Edition DeBruyne ■ Pinna © Cengage Learning 2014 Health Effects and Recommended Intakes of Fats (cont’d.) Dietary Guidelines for dietary cholesterol –Healthy people: less than 300/day –People with or at high risk of heart disease: less than 200 mg/day Monosaturated fat (olive oil) –May prevent heart disease Omega-6 and omega-3 fats –Lower total cholesterol and LDL

Nutrition for Health and Health Care, 5th Edition DeBruyne ■ Pinna © Cengage Learning 2014 Health Effects and Recommended Intakes of Fats (cont’d.) EPA and DHA heart health benefits –Lower blood triglycerides –Prevent blood clots –Protect against irregular heartbeats –Lower blood pressure –Defend against inflammation Food sources of omega-3 and omega-6 Fatty Acids (Table 4-4)

Nutrition for Health and Health Care, 5th Edition DeBruyne ■ Pinna © Cengage Learning 2014 Health Effects and Recommended Intakes of Fats (cont’d.) What concerns are associated with taking omega-3 supplements? Recommendations for fat intake –Dietary Guidelines Diet low in saturated fat, trans fat, and cholesterol 20 to 35 percent of daily energy –FDA Daily Values 30 percent of daily energy

Nutrition for Health and Health Care, 5th Edition DeBruyne ■ Pinna © Cengage Learning 2014 Fats in Foods

Nutrition for Health and Health Care, 5th Edition DeBruyne ■ Pinna © Cengage Learning 2014 Fats in Foods (cont’d.) Foods with five grams (45 kcal) pure fat: –1 tsp. oil or shortening, 1 ½ tsp. butter, 1 Tbsp. salad dressing, 1 ½ Tbsp. of sour cream, etc. Invisible fats –Majority of solid fats in U.S. diet Milk and yogurt –Varying fat content –Rich in calcium and protein

Nutrition for Health and Health Care, 5th Edition DeBruyne ■ Pinna © Cengage Learning 2014 Fats in Foods (cont’d.) Meat categories by fat content –Very lean, lean, medium-fat, and high-fat USDA Food Patterns protein recommendation for adults –Five to seven ounces per day Most vegetables and fruits –Little or no fat

Nutrition for Health and Health Care, 5th Edition DeBruyne ■ Pinna © Cengage Learning 2014 Fats in Foods (cont’d.) Most grains have small amounts of fat Dietary Guidelines regarding fat intake 1.Select the most nutrient-dense foods from all food groups 2.Consume fewer and smaller portions of foods and beverages containing solid fats

Nutrition for Health and Health Care, 5th Edition DeBruyne ■ Pinna © Cengage Learning 2014 Fats in Foods (cont’d.) Dietary Guidelines regarding fat intake 3.Replace solid fats with liquid oils 4.Check Nutrition Facts labels and select foods with little saturated fat and no trans fat Solid fat ingredients –Butter, coconut oil, palm oil, shortening, etc. –Solid fat ingredients listed on food labels (Table 4-6)

Nutrition for Health and Health Care, 5th Edition DeBruyne ■ Pinna © Cengage Learning 2014

Nutrition for Health and Health Care, 5th Edition DeBruyne ■ Pinna © Cengage Learning 2014

Nutrition for Health and Health Care, 5th Edition DeBruyne ■ Pinna © Cengage Learning 2014

Nutrition for Health and Health Care, 5th Edition DeBruyne ■ Pinna © Cengage Learning 2014 Fats in Foods (cont’d.) Do not overdo fat restriction –Include a teaspoon of fat in every meal Fat-reduced products –Fat replacers –Artificial fats –Preparation methods Whipping air into foods, baking foods vs. frying, adding fat-free milk, etc.

Nutrition for Health and Health Care, 5th Edition DeBruyne ■ Pinna © Cengage Learning 2014

Nutrition for Health and Health Care, 5th Edition DeBruyne ■ Pinna © Cengage Learning 2014

Nutrition for Health and Health Care, 5th Edition DeBruyne ■ Pinna © Cengage Learning 2014 Fats in Foods (cont’d.) Alternatives to fat in supporting weight loss –Must actually replace fat and energy in the diet Food labels –List total fat, saturated fat, trans fat, cholesterol, and fat kcalories per serving –Easy to compare similar products