HNSC 2170: Unit 3 Lipids

Explain the role of fats in the body

Energy storage, padding, insulation, form cell membranes, converted into other materials

What are the different types of lipids?

Triglycerides, phospholipids, sterols

What are triglycerides?

Main form found in body & foods, composed of 3 fatty acids and 1 glycerol backbone

What are phospholipids?

Soluble in fat & water, composed of 2 fatty acids, 1 phosphate group, 1 glycerol backbone, and choline molecule

What are sterols?

Large, complex molecules of interconnected rings of C, including cholesterol, vit D, sex hormones, bile

What is the difference between saturated and unsaturated fatty acids?

Saturated FA: every avail C filled to capacity w/ H atoms, single bonds; Unsaturated FA: some H atoms missing in FA chains, missing points = points of unsaturation, chain containing point of unsat = unsaturated FA - at least 1 double bond

What is the difference between monounsaturated and polyunsaturated fatty acids?

Monounsaturated: 1 double bond; Polyunsaturated: 2 or more double bonds

What is the difference between omega-3 and omega-6 fatty acids?

Omega-3: first double bond at 3rd C from omega end; Omega-6: first double bond at 6th C from omega end

What are essential fatty acids?

Fatty acids that cannot be synthesized by the body and must be obtained from the diet

What are some examples of omega-3 fatty acids?

Alpha-linolenic acid (ALA), eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA)

What are trans fatty acids?

Unsaturated fatty acids with trans double bonds, often found in processed foods

What is the difference between cis and trans fatty acids?

Cis: H atoms on same side of double bond, bent shape; Trans: H atoms on opposite sides of double bond, straight shape

What is the function of lipoproteins?

Transport lipids in the blood

What are the different types of lipoproteins?

Chylomicrons, very low-density lipoproteins (VLDL), low-density lipoproteins (LDL), high-density lipoproteins (HDL)

What is the function of chylomicrons?

Transport dietary lipids from the small intestine to the liver and other tissues

What is the function of VLDL?

Transport lipids synthesized in the liver to other tissues

What is the function of LDL?

Transport cholesterol to tissues for various functions

What is the function of HDL?

Transport cholesterol from tissues back to the liver for disposal

What is 1 point of unsaturation?

ex. oleic acid in olive oil

What is polyunsaturated?

2 or more points of unsaturation, omega-6, linoleic acid - omega-3, linolenic acid, EPA (eicosapentaenoic acid), DHA (docosahexaenoic acid), found in oils of some fish (deep sea, fatty fish (salmon, char, mackerel, herring, cod, etc), human milk)

What are hard and soft fats?

shorter chain, unsat = softer at room temp; melt more readily, ex. lard, chicken fat, safflower oil, lard = ↑saturated ∴ hardest, chicken fat = ↓saturated ∴ soft, safflower oil = unsaturated ∴ liquid

What is stability?

rancid, exposed to O2, polysat FAs, oxidation of unsat fats, sat fats ↑resistant or oxidization ∴ ↓rancid

What is hydrogenation?

adding H atoms to points of unsaturation, makes polyunsaturated fats more saturated, prolongs shelf life (protects against oxidation), ↑solidity, produces trans fatty acids

What is the difference between saturated, unsaturated, and trans fats?

Saturated: solid at room temp, ↑risk of heart disease, foods: cheese, meats. Unsaturated: ↓risk of heart disease, foods: olive oil, avocado. Trans fats: ↑risk of heart disease, foods: fries, chips, candy.

What is the goal of fat digestion?

Breakdown triglycerides → monoglycerides, FAs, glycerol - smaller molecules body can absorb & use.

What is the role of dietary fats in cardiovascular disease risk?

R/t LDL & HDL levels. ↑LDL = ↑risk of CVD, earlier the event occurs. ↓LDL by maintaining healthy body weight, ↑soluble fibre intake, ↓sat & trans fat intake. ↓HDL = ↑risk of CVD. ↑HDL by maintaining healthy body weight, regular PA, quit smoking.

What are some foods high in saturated fats?

Meats, bacon, cheese, whole milk products, butter, cream cheese, sour cream, shortening, lard, oil (coconut, palm).

What are some foods high in trans fats?

Fried foods, fast foods, margarine, baked goods (donuts, cakes, cookies), snacks (popcorn, chips, crackers).

What is the role of dietary cholesterol on blood cholesterol values?

Little to no effect on blood cholesterol levels.

What are some dietary interventions to lower the risk of cardiovascular disease?

↓sat fat to >7% of total kcal, replace with unsat fats (fish, veg oil, nuts, or with carbs from whole grains, legumes, fruits, & veg), avoid trans fat, choose ↑soluble fibre foods (oats, barley, legumes, fruits).

What are some lifestyle interventions to lower the risk of cardiovascular disease?

PA, ↓sat/trans fats, ↑unsat fat.

What is physical activity?

Any bodily movement that requires energy expenditure.

What are the dietary interventions to manage hypertriglyceridemia?

Decrease alcohol and refined carbohydrate intake.

What are the lifestyle interventions to manage hypertriglyceridemia?

Maintain healthy body weight and engage in regular physical activity.

What are the potential health benefits of omega-3 fatty acids?

Protect against heart disease, lower blood triglycerides, protect against irregular heartbeats, lower blood pressure, defend against inflammation.

What are the risks associated with omega-3 fatty acids?

Increased LDL cholesterol, suppressed immune system, and affected wound healing.

What is the recommended way to increase intake of omega-3 fatty acids?

Increase fatty fish consumption to at least two 3.5 oz servings each week. Choose fish with low mercury levels such as salmon, sardines, canned light tuna, and catfish over fish with high mercury levels such as king mackerel and swordfish. Choose foods over supplements.

What is metabolic syndrome?

A cluster of metabolic abnormalities associated with an increased risk of cardiovascular disease and type 2 diabetes.

What are the diagnostic criteria for metabolic syndrome?

Presence of at least three of the following: hyperglycemia, abdominal obesity, hypertriglyceridemia, low HDL cholesterol, and hypertension.

What are the nutrition recommendations for dietary fats?

AMDR fat = 20-35%, saturated fat <10%, trans fat 0mg, omega-6 5-10%, omega-3 0.6-1.2%, 2-3g EPA & DHA daily, sodium <1500 mg/daily, cholesterol <300 mg/daily.

What are some food sources of monounsaturated fats?

Avocados, canola oil, olive oil, peanut oil, sesame oil, almonds, cashews, and peanuts.

What are some ways to lower overall fat intake?

Choose lean meats, low-fat dairy products, and limit intake of high-fat snacks and desserts. Use cooking methods such as grilling, baking, and broiling instead of frying.

What are some examples of polyunsaturated fats?

olives, peanut butter, sesame seeds

What are some examples of omega-6 fatty acids?

margarine, corn oil, walnuts, mayo, salad dress, pumpkin seeds

What are some food examples of omega-3 fatty acids?

fatty fish, walnuts, canola/soybean/walnut oil, yeast

What are some examples of saturated fats?

meats, bacon, cheese, whole milk products, butter, cream cheese, sour cream, shortening, oil (coconut/palm)

What are some examples of trans fats?

fast food, fried foods, baked goods (donuts, cakes, cookies), popcorn, chips, crackers, margarine (hydrogenated)

What are some ways to lower fat intake?

fat-free milk, eat less meat, olestra, artificial fats

What are the health benefits of the Mediterranean diet?

fresh, whole foods, ↑mono & polyunsaturated fats, starch & fibre-rich carbs, ↓CVD risk via ↓blood CFs, BP, total & LDL cholesterol

What are the health benefits of olive oil?

good for the heart as lowers BP, ↓CVD risk via ↓blood CFs, BP, total & LDL cholesterol

What are the health benefits of nuts?

↓CVD & diabetes risk, contain mono & polyunsaturated fats than saturated fats, almonds, cashews, walnuts, peanuts

What are the health benefits of fish?

↓CVD risk, good for heart, best source of EPA & DHA, though may contain mercury