1. Review normal regulation glucose and Diabetes module
What are all the things that insulin does? Glucagon?
Some body cells use fat for energy, which are the ones that always prefer glucose? (pg 125)
Contrast T1 and T2 DM, with regard to: wt at dx, rate T1 vs T2, incidence rates in US (overall and over 65), insulin resistance, autoimmune response.
Factors that increase insulin resistance?
Is gestational DM more related to T1 or T2? Does managing GDM usually require meds?
How does a pt w/ DM give themselves insulin?
How does serum Vit D status relate to risk of develop DM?
Is it OK for person w/ DM to eat carbohydrates? What type of carbs would you advise that person to consume? Not consume?
Ranges of fasting blood sugar and A1c to differentiate nl/pre-/ DM?
List 4-5 complications to be avoided? How to avoid?

2. Selected Portions Chapter 5: The Lipids
Valerie Schulz, MMSc, RD, LD/N, CDE

3. Objectives
Discuss if a moderate intake of lipids is an essential part of a healthy diet.
Compare and contrast the physical properties and the sources of saturated, monounsaturated and polyunsaturated fats.
Describe how/where dietary lipids are broken down / absorbed during digestion and how transported through body.
Describe the roles of omega-3 and omega-6 fatty acids in the body, and discuss which one is usually too low, and how it can be increased.
Describe the formation and structure of trans-fats; state ways consumers may reduce intakes.
Discuss evidence for the benefits/drawbacks of specific dietary fats in terms of their potential effects on human health.

4. Discussion When humans make fat, what kind is it?
If we don’t eat fat, can we/will we still make fat? When would that occur? If fat is not eaten, from what would we make fat?
Should we eat fat? Are there essential fatty acids?
If so, what kind of fat?
What benefit does fat provide to us?

5. Review of lipids
Lipids in foods and the human body fall into three classes:
Tri_____________ (about 95%)
P_________lipids
S_________
Tissues all over the body can assemble or disassemble triglycerides as needed.

6. Saturated versus Unsaturated _________ ___________

7. Phospholipids Phospholipid
Glycerol + __ (how many) fatty acids + phosphorus
Phosphorus part makes it soluble in _________
Fatty acids make it soluble in ______
Therefore can serve as an emulsifier
Key role is in cell membranes

8. phospholipid Phosphate, chains of carbon atoms
© 2012 John Wiley & Sons, Inc. All rights reserved.

9. Sterols
Sterols
Large molecules consisting of interconnected rings of carbon atoms with side chains of carbon, hydrogen, and oxygen attached
Cholesterol
is found in all (animal or plant?) cell membranes
(Is or is not?) essential (Remember definition of essential)
forms plaques that cause atherosclerosis
Cholesterol serves as the raw material for
bile
vitamin D
steroid hormones including the sex hormones

10. sterols Multiple chemical rings
© 2012 John Wiley & Sons, Inc. All rights reserved.

11. Digestion and absorption
Mouth and stomach: nothing but chewing
In the stomach, fat floats on the watery fluids.
In the small intestine, bile emulsifies fat. (Where does bile enter?) Enzymes accomplish most fat digestion, cleaving triglycerides into glycerol, free fatty acids and monoglycerides. These are then absorbed into intestinal cells, from those cells into the lymph, and finally into the blood (by connecting with the left subclavian vein).
Large intestine: Fats should all be absorbed in small intestine. Whatever cholesterol is trapped with (soluble) fiber exits with feces.
Absorption of chylomicrons (from Wikipedia): Chylomicrons are created by the absorptive cells of the small intestine, known as enterocytes. They are relatively large, having a diameter of 75 to 1,200 nm. These nascent chylomicrons are released by exocytosis from enterocytes into lacteals, lymphatic vessels originating in the villi of the small intestine, and are then secreted into the bloodstream at the thoracic duct's connection with the left subclavian vein. In adults, the thoracic duct transports up to 4 L of lymph per day.
The lymph transport in the thoracic duct is mainly caused by the action of breathing, aided by the duct's smooth muscle and by internal valves which prevent the lymph from flowing back down again.
There are also two valves at the junction of the duct with the left subclavian vein, to prevent the flow of venous blood into the duct.

12. Digestion and Absorption of Fats

13. Lipoproteins
The just-eaten fat travels in the bloodstream as chylomicrons.
Body tissues can extract whatever fat they need from chylomicrons.
The remnants are then picked up by the liver, which dismantles them and reuses their parts.
Lipoproteins are made in the body, not eaten (we don’t eat HDL or LDL, we make it)

14. Major Lipoproteins: VLDL, LDL, HDL
In addition to the chylomicron, the body uses three other types of lipoproteins to carry fats:
Very-low-density lipoproteins (VLDL), which carry triglycerides and other lipids made in the liver to the body cells for their use.
Low-density lipoproteins (LDL) transport cholesterol and other lipids to the tissues. LDL are made from VLDL after they have donated many of their triglycerides to body cells.
High-density lipoproteins (HDL), which are critical in the process of carrying cholesterol away from body cells to the liver for disposal.

15. Major Lipoproteins: LDL, HDL – pg 162 Heading: Lipoprotein and Heart Disease risk

16. Compare LDL to HDL LDL HDL Size Larger Smaller Cholesterol More Less
Protein
Triglycerides and cholesterol to the tissues
Deliver
Remove
Inflammation
Increases
Decreases
Risk of CVD
Increased when higher
Decreased when higher
Oxidation
More susceptible, has more fat. May trigger damage to arteries.

17. How LDL becomes increased
Consumption of:
saturated fats
Trans fats
Sources of saturated fats
Figures 5-10 and 5-11 in Sizer, pgs , headings LO 5.4 Dietary Fat, Cholesterol and Health (Fig 5-11 also later in this power point)
Sources of trans fat
MeettheFats/The-Bad-Fats- Brothers_UCM_305102_Article.jsp#.TzNcYPmLK7t
Click on the trans fats cartoon guy, then on ‘Their Menu’, then ‘Trans faves’. You can see the amounts of trans fats as you roll the cursor over the foods. If you hover over ‘Trans’ face, he says some silly things…

18. How to raise HDL
Certain changes in lifestyle may have a positive impact on raising HDL levels:[21]
Aerobic exercise[22]
Weight loss[23]
Nicotinic Acid supplementation[23]
Smoking cessation[23]
Removal of trans fatty acids from the diet[24]
Mild to moderate alcohol intake[25][26][27][28][29][30]
Addition of soluble fiber to diet[31]
Consumption of omega-3 fatty acids such as fish oil[32] or flax oil[citation needed]
Increased intake of cis-unsaturated fats[33]
Decreased intake of simple carbohydrates.[34][35][36][37]
Higher levels of HDL are correlated with lower levels of heart disease

19. Usefulness of Fats in the body
Energy stores: chief storage for kcal eaten in excess of need
Muscle fuel: most of the energy for muscular work
Emergency reserve: in times of illness and diminished food intake
Padding: cushion internal organs and under skin
Insulation: fat layer under skin insulates against temp changes
Cell membranes: fats form major material of membranes
Raw materials: for hormones, bile, Vitamin D

20. Usefulness of fat in foods
Nutrient: essential fatty acids (EFA)
Energy: concentrated kcal source
Transport: carry fat-soluble vitamins
Sensory appeal: fats contribute to taste and smell of foods
Satiety: fats contribute to feelings of fullness
Texture: Fats help make foods tender (cookies, cakes, biscuits – the word ‘shortening’ refers to shortening the gluten strands in foods made with flour, thus allowing tenderness)
Traces of fats and oils are present in almost all foods, so even without purposely eating extra we would still intake some fat.

21. Not so useful: Trans fats
© 2012 John Wiley & Sons, Inc. All rights reserved.

22. Health Effects of lipids
Risks of trans fats:
Like SFA, trans fats increase LDL and risk of heart dz
Sources:
Commercially prepared cakes, cookies, donuts, pastries, hi fat crackers, fast foods, margarine (esp stick versions), deep-fried foods (french fries!), [small amounts naturally occurring in meat & dairy – very insignificant]
Increasing daily trans fat consumption from .9% to 2.1%, or from two grams to 4.67 grams, will increase one's risk of cardiovascular disease by 30%.

23. Health Effects of lipids
To reduce trans fats
Choose instead: home-prepared cake (oil); cookies made w/ applesauce or date puree or grd flaxseed in place of some of the shortening/butter; omit donuts & pastries most of the time; lower fat/higher fiber crackers (Triscuits instead of Ritz); tub or liquid margarine, esp light versions; substitute salad or another vegetable for french fries and choose grilling/ broiling / baking/roasting instead of deep frying
Quick: Have you already exceeded the daily recommended limit for trans fat intake today?

24. Calculate the trans-fat
A bag of chips has 8 servings and has a trans-fat free label
Each serving has 0.4 g of trans fat (label lists as 0 g of fat)
If you eat ½ of the bag of chips, how many grams of trans-fat have you consumed?
This can be individually or in pairs then done at the board by the instructor. Answer = 1.6 g.
© 2012 John Wiley & Sons, Inc. All rights reserved.

25. Health Effects of lipids
Risks from saturated fats:
Raises LDL, increased risk of heart disease
Sources of saturated fats:
whole and 2% milk; cream (like whipped cream, full fat cream cheese); butter; full fat cheese; premium, regular & reduced fat ice cream.
Fatty cuts of beef (like prime); pork; chicken skin
Coconut, palm and palm kernel oils (“tropical”)
Choose instead: skim or 1% milk; reduced fat (2%) cheese and cream cheese (1% milk & reduced fat cheeses still have saturated fat, just less), & whipped cream; spreadable butter/oil blend; reduced fat ice cream; lean cuts meat, skinless chicken; avoid tropical oils

26. Lowering LDL Cholesterol – Figure 5-11, pg 165

27. Introduction to Omega-3 and Omega -6

28. Saturated versus Unsaturated Fatty Acids

29. Omega-6 And Omega-3 Fatty Acid Families
Linoleic acid is the “parent” member of the omega-6 fatty acid family
Abundant in vegetable oils from land plants
Linoleic acid can be elongated to other members of this family, for example, arachidonic acid
Linolenic acid is the “parent” member of the omega-3 fatty acid family
Linolenic acid can be elongated to make other members of this family, for example, EPA and DHA

30. Benefits of Omega-3 long chain fats
EPA and DHA:
Longer chain (20 & 22 carbons) fats
are made in limited amounts by humans
abundant in fish oils
lower blood pressure
prevent blood clot formation
protect against irregular heartbeats
may reduce inflammation
essential for normal infant growth and development
may support immune system
may inhibit cancers

31. Health Effects of lipids
Benefits of longer chain omega-3 fats:
Reduces risks of heart attacks and strokes. Supports healthy immune system and decreases inflammation.
Sources of plant forms: organic canola or soy oil, chia, flaxseed oil (grd flaxseed); walnuts
Sources of animal forms: fatty fish (salmon, herring, mackerel, sardines, tuna) Recommended 2x/wk
Fish oil or flaxseed oil supplements: OK if not overdone – high intakes (> 1g/d) can increase bleeding time and suppress immune function