1. Lipid Functions -In food -In your body -Types of fats in foods -Fat recommendations

2.  Why are diets that are very low in fat not healthy?

3. Lipid functions in the body

4. Lipid Function in the Body - Energy  The structure of lipids makes them bundles of energy  They contain more kcals per gram then carbohydrates or proteins because of their structure of long chains of carbons and hydrogens

7. Lipid Functions in the Body – Phospholipids  Phospholipids are most known for the fact that they make up cell membranes  They do exist outside membranes ♦ Surfactants in lungs (wetting properties) ♦ Component of bile (detergent properties)

8. Cholesterol

9. Functions in the Body –Cholesterol  Cholesterol is vital in producing vitamin D and some hormones (sex hormones)  Maintains structure of cell membranes  Digestion: precursor for bile  Important in nervous system; is 1/5 of myelin sheath of nerve cells; brain contains 25% of body’s cholesterol

10. Cholesterol  Cholesterol your body needs is made by the liver; dietary cholesterol is useless Functions of Lipids: Lipoproteins  Lipoproteins carry cholesterol and triglycerides around in the blood  HDL: “Good cholesterol”  LDL: “Bad cholesterol”

11. Lipoprotein

12. Triglyceride Function – in the body  Energy source and energy storage  Transportation and storage of fat soluble vitamins  Insulation  Cushioning and protection

13. Functions of fats in food

14. Functions of Fats in Foods  Tenderizers ♦ That flaky, light texture of baked goods  Aerations ♦ Fat can form air bubbles in batter and dough  Emulsions ♦ A mixture of two unmixable substances ♦ Butter, milk, mayonnaise  Flavor ♦ Fats give some characteristics flavors

15. Commercial Uses of Fats HHydrogenation ♦C♦C hemical process in which hydrogen is added to unsaturated fats ♦I♦I t is possible to partially hydrogenate TThis changes liquid oils to semi- solid fats (adds “spreadableness”)

16. Trans Fat – “Double Whammy”  The result of the process of hydrogenation  Lowers HDL and raises LDL  Can build up in arteries and form plaques which increase the risk of heart disease & other related diseases

17. Sub-Types of Fats in Foods Food Sources of Fats  Milk fats  Animal fats  Vegetable butters (cocoa butter)  Marine (fish oils)  Fats with oleic or linoleic acids (corn, sunflower, olive oils)  Fats with linolenic acid (soybean oil)

18. Fat Replacements  Mimic fats  Can be protein, carb, or fat based ♦ Each provide less calories  Calorie free ♦ Olestra

19. Fat Recommendations  Keep total fat intake between 20 to 35 percent of calories, with most fats coming from sources of polyunsaturated and monounsaturated fatty acids, such as fish, nuts, and vegetable oils.  Lean, low-fat, or fat-free choices  Limit intake of fats and oils high in saturated and/or trans fatty acids

20. The Fate of Dietary Fat  Fats (triglycerides) in food are broken down into fatty acids and glycerol and absorbed in your digestive system ♦ Some are stored in the liver  Converted to glycogen or left as is  Excess fats end up in adipose tissue throughout the body