NUT 2202 Lecture 16: Outline 6 The Lipids and Related Micronutrients

24 Pages
Unlock Document

Appalachian State University
NUT 2202
Laura Helena Mc Arthur

NUT 2202 Nutrition and Health The Lipids and Related Micronutrients I. Introduction to the Lipids A. Nutrient category 1. Units of measure used to determine human requirements B. Lipid diversity – some are big, some are little C. Chemical composition of lipids – ALL ORGANIC, some contain phosphorous D. Categories of lipids in the body and in food 1. Categories in the body a. triacylglycerols (TAGs)—made up of 3 fatty acids attached to a backbone of glycerol **most abundant type of food fat** b. phospholipids – lipid + phosphorous with backbone of glycerol c. cholesterol—building block for different things 2. Categories in food E. Fats versus oils Solid vs Liquid depends on what TAGs involved 1. Composition of solid fats and liquid oils – BOTH made of Triacylglycerols II. The Fatty Acids A. Occurrence of fatty acids in the body and in food 1. Most common form – find them as TAGs (3 pack) 2. Less common forms – independent fatty acids B. Dietary sources of fatty acids and TAGs 1. Plant foods – coconuts, avocado, olives 2. Animal foods – beef, poultry, cheese, C. Chemical composition of fatty acids – Carbon, Hydrogen, Oxygen D. Chemical structure of fatty acids 1. Carbon chain 2. Acid group 3. With or without carbon-carbon double bonds – UNSATURATED FATTY ACID E. Chain length of fatty acids 1. Short-chain: Contain fewer than 6 carbon atoms 2. Medium-chain: Contain 6, 8 or 10 carbon atoms. 3. Long-chain: Contain 12 to 24 carbon atoms. F. Classification of fatty acids 1. Saturated versus unsaturated fatty acids a. Structure – how long is carbon chain? * Saturated fatty acids: no double bonds * Monounsaturated fatty acids: one double bond * Polyunsaturated fatty acids: two or more double bonds b. Health implications * Saturated fatty acids: raise LDL-c or unfavorably impact TL-c to HDL-c concentration, promote cholesterol synthesis, promote CVD. * Monounsaturated fatty acids: lower LDL-c concentrations or have a favorable impact on TL-c to HDL-c ratio, lower blood TAG concentration, do not lower HDL-c concentration, promote heart health. * Polyunsaturated fatty acids: lower LDL-c concentration or have a favorable impact on TL-c to HDL-c ratio, lower blood TAGs, promote heart health. • An optimal TL-c to HDL-c radio is <3.5 mg of TL-c to 1.0 mg of HDL-c higher c. Dietary sources * Saturated fatty acids: whole milk dairy foods, meats, coconut oil * Monounsaturated fatty acids: canola and olive oils, avocadoes, nuts. featured heavily in Mediterranean diet. * Polyunsaturated fatty acids: fatty fish (e.g., salmon, mackerel, tuna), vegetable oils (e.g., corn, safflower, soybean, sunflower), seeds. d. Examples * Saturated fatty acid: myristic acid * Monounsaturated fatty acid: oleic acid * Polyunsaturated fatty acid: alpha-linolenic and linoleic acid alpha—omega 3 linoleic—omega 6, 2. Trans fatty acids – 0% of calories should come from trans fat, pump hydrogen atoms into substance a. Structure: long-chain, polyunsaturated b. Health implications * Raise blood TL-c, LDL-c, and TAG concentrations * Lower blood HDL-c concentration * Pro-inflammatory – cause inflammation in blood vessels * Promote CVD c. Dietary sources: fast foods, snacks, hydrogenated/partially hydrogenated margarines/spreads, very little in dairy foods and read meats d. Example: elaidic acid 3. Omega-3 versus omega-6 fatty acids a. Structure * Omega-3: polyunsaturated, long-chain * Omega-6: polyunsaturated, long-chain b. Health implications * Omega-3: anti-inflammatory, stabilize heartbeat, lower TL-C and LDL-c, lower blood TAGs concentration, prevent blood clots, dilate blood vessels, promote normal vision, promote normal brain functioning Friendly to heart health ☺ * Omega-6: pro-inflammatory, promote blood clots, lower LDL-c and TL-c concentrations, promote heart health. c. Dietary sources * Omega-3 fatty acids: fatty fish (e.g., herring, rainbow trout, mackerel, salmon, and tuna), flaxseed, canola oil, walnuts. * Omega-6 fatty acids: vegetable oils (e.g., corn oil, safflower oil, sunflower), seeds, and meats. d. Examples * Omega-3 fatty acids: Alpha-linolenic acid, EPA, and DHA * Omega-6 fatty acids: linoleic acid e. Deficiency symptoms * Omega-3 fatty acids: cardiac arrhythmias, vision problems, learning problems in children, polydypsia * Omega-6 fatty acids: skin lesions, growth retardation in children, reproductive failure, polydypsia 4. Essential versus nonessential fatty acids a. Names of essential fatty acids – alpha-linolenic acid (Omega 3 & polyunsaturated) linoleic acid ( Omega 6 & polyunsaturated) b. Deficiency symptoms (essential fatty acids only): reproductive failure; liver and kidney disorders; dry, scaly skin; growth and developmental abnormalities; poor wound healing; vision and hearing problems; CVD problems c. Dietary sources Effects of Fatty Acids on Heart Health _________________________________________________________________ Type of Increases/ Mechanism Fatty acid decreases of action risk of CVD Saturated Increase (look in notes) Monounsaturated Decrease Lower LDL Polyunsaturated Decrease Lower LDL, good TL-c, not lower HDL Trans Increase raise LDL, cause inflammation, BAD BAD BAD Omega-3 Decrease (look in notes) Omega-6 Increase (look in notes) _________________________________________________________________ III. The Triglycerides or Triacylglicerols (TAGs) A. Occurrence of the TAGs in the body and in food 1. Occurrence in body – adipose tissue, liver and muscles, protecting kidneys, blood stream Fat Cell 2. Occurrence in food – red meat, whole milk, butter, oils B. Chemical composition and structure of TAGs – 3 fatty acids attached to glycerol backbone 1. Backbone structure 2. Fatty acids C. Dietary sources of TAGs 1. Plant Foods – OILS 2. Animal foods – fat in meals, butter D. Functions of TAGs 1. Functions in food – give FLAVOR ☺ affects appearance, give food calories 2. Functions in the body – calorie reserve E. Health implications of TAGs 1. Risk factor – High TAGs, 2. Recommendation for healthy adults with zero or one unimportant risk factor for CVD: < 150 mg/dL fasting blood IV. The Phospholipids lecithin Acetylcholine A. Occurrence of Phospholipids in the body and in food 1. Occurrence in body – cell membranes 2. Occurrence in food – egg yolk, mayonnaise, soy beans, chocolate B. Chemical composition and structure of phospholipids Lecithin 1. Backbone structure – GLYCEROL ☺ 2. Fatty acids 3. Phosphate group 3. Compound attached to phosphate group – choline can attach to phosphate group ☺ 5. Names of phospholipids: lecithin and acetylcholine lecithin  acetylcholine (in brain) (add choline to phosphate group and get lecithin) ***acetylecholine found in brain that helps your memory Lecithin Acetylcholine C. Properties of phospholipids – transporter ☺ 1. Solubility D. Functions of phospholipids in food and in the body 1. Functions in food: emulsifiers -- keep ingredients from separating 2. Functions in the body * Lecithin: Made in brain. Used to make acetylcholine. * Acetylcholine: made in the brain from lecithin. Stimulates production of HCl in stomach. Used by memory center of the brain. V. Cholesterol A. Occurrence of cholesterol in the body and in food 1. Occurrence in the body: blood; liver; skin (can be in muscle too) 2. Occurrence in food: foods of animal origin B. Chemical composition and structure of cholesterol C. Health implications of high cholesterol and recommendations 1. Health implication – HDL-c (keep it high); if get too much LDL-c (keep it low)= clog arteries 2. Recommendations for healthy adults with zero or one unimportant risk factor for CVD a. TL-c recommendation for healthy adults: < 200 mg/dL fasting blood b. LDL-c recommendation for healthy adults: <100 mg/dL fasting blood ** Destination: BLOOD - Grade A- optimal (less than 100) -Grade B- desirable (not that great) c. HDL-c recommendation for healthy adults >= 40 mg/dL fasting blood ** Destination: LIVER -- smoking will lower HDL-c -- sedentary lifestyle lowers HDL-c D. Functions of cholesterol in food and in the body 1. Functions in food – Import
More Less

Related notes for NUT 2202

Log In


Don't have an account?

Join OneClass

Access over 10 million pages of study
documents for 1.3 million courses.

Sign up

Join to view


By registering, I agree to the Terms and Privacy Policies
Already have an account?
Just a few more details

So we can recommend you notes for your school.

Reset Password

Please enter below the email address you registered with and we will send you a link to reset your password.

Add your courses

Get notes from the top students in your class.