Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
64 Cards in this Set
- Front
- Back
|
Lipids are.... |
Organic compounds, insoluble in water |
|
|
Fats are... |
Lipids that are solid at room temperature |
|
|
Oils are... |
Lipids that are liquid at room temperature |
|
|
Three types of fats |
Triglycerides, phospholipids, sterols |
|
|
Triglycerides |
Chief form of fat in foods and human body 3 units of fatty acids attached to a glycerol -> fatty acids differ in chain length and saturation |
|
|
Saturated fat characteristics |
Straight chains, solid at room temperature, entirely hydrated (no double bonds) |
|
|
Monounsaturated fatty acids |
one double bond (one point of unsaturation) |
|
|
Polyunsaturated fatty acids |
two or more double bonds (points of unsaturation) |
|
|
Saturated fats and health |
May contribute to elevated LDL cholesterol Known to elevate risk of heart disease |
|
|
LDL Cholesterol |
Low Density Lipoproteins Takes cholesterol from liver and delivers it to blood and tissues |
|
|
Monounsaturated Fatty Acids and Health |
May help lower LDL cholesterol - does not lower HDL cholesterol Fairly resistant to oxidation |
|
|
HDL Cholesterol |
"Good" cholesterol High-density lipoproteins Takes cholesterol from blood and tissues to liver |
|
|
Polyunsaturated Fatty acids |
Provide raw material for eicosonoids Essential fatty acids -> omega-3 and omega-6 |
|
|
What do Eiocosanoids do? |
Hormone-like functions -> muscle relaxation/contraction, blood vessel dilation/constriction, blood clot formation... Structural and functional parts of cell membrane Contribute to lipids to brain and nerves Promote growth and vision, assist in gene regulation Support immune function, help brain develop |
|
|
Another name for Omega-3 |
Linolenic acid |
|
|
Omega-3 Functions |
Lowers blood pressure, lowers total cholesterol and LDL, raises HDL Supports immune system, anti-cancer functions |
|
|
Another name for Omega-6 |
Linoleic acid |
|
|
Omega-6 Functions |
Makes arachidonic acid, hormone-like substances May lower HDL (that's bad) - only good in excess |
|
|
Food sources of essential fatty aids |
Linolenic acid - oils, nuts and seeds, soy beans, flat beans Linoleic acid - leafy veggies, nuts, seeds, grains, veggie oils EPA and DHA - human milk, omega-3 milk/eggs, fatty coldwater fish |
|
|
Benefits of Fish oil Supplements |
Heart disease prevention, infant growth and development, cancer prevention |
|
|
Cons of Fish oil Supplements |
May interfere with healing, raise LDL, have toxins, lacking in iodine, selenium, and protein (no substitute for fish) |
|
|
What are trans fatty acids? |
Novel fatty acids formed during hydrogentation of unsaturated fatty acids May be worse than saturated fatty acids - raises LDL AND lowers HDL |
|
|
Where you can find trans fatty acids |
Chips, butters, baked good, margarine |
|
|
Why are they hydrogenated? |
Increases shelf life, raises smoking point, harder and more stable/spreadable |
|
|
What are phospholipids? |
Similar structure to triglycerides, but have a phosphorous-containing acid (in place of a fatty acid) |
|
|
Why are phospholipids significant? |
Are soluble in water and fat (phosphorous soluble in water, fat soluble in fat) |
|
|
Function of phospholipids |
Emulsifier of fat, found in cell membranes |
|
|
Example of a phospholipid |
Lecithin |
|
|
Why is lecithin important? |
Helps fat travel across lipid-containing membrane into watery fluids
Key role in cell membranes |
|
|
Where is lecithin found? |
In liver, also found in foods |
|
|
What are sterols? |
Large molecules - rings of C with side chains of C, H, O |
|
|
Why are sterols important? |
Play important roles as part of vitamin D, sex and steroid hormones |
|
|
Example of sterols |
Cholesterol |
|
|
Why is cholesterol made in the body? |
For bile and an emulsifier of fat Part of cell membrane and necessary for body |
|
|
Problems with cholesterol |
Forms major part of plaque in arteries Can only control 20% of cholesterol in diet - more genetic |
|
|
What does cholesterol do with respect to bile? |
Cholesterol is a raw material for bile, stored in gallbladder Emulsifies fats so enzymes can get at them in watery stomach fluids |
|
|
Foods high in saturated fatty acids and trans fat (may do what to cholesterol) |
Raise LDL blood cholesterol |
|
|
High blood cholesterol is an indicator of... |
risk for cardiovascular disease |
|
|
Usefulness of fats in body |
Body padding, body insulation, in cell membranes, raw materials for hormones, bile and vitamin D |
|
|
Where are the fat deposits in the body? |
Muscle, breasts, fat under skin Differences between visceral fat and subcutaneous fat |
|
|
When is fat used for energy? |
During AEROBIC exercise used as fuel WITH GLYCOGEN is a chief form of stored energy |
|
|
How stored fat is used for energy |
drawn when fuel from foods is low, and fatty acids are released into blood fatty acids combine with glucose and energy, carbon dioxide and water released (Kreb's and ETC) Carbohydrates needed when body fat is broken down to prevent build up of ketone bodies in blood of urine |
|
|
Digestion of fats |
In mouth - lingual lipase - digests milk fats (in infants) in stomach - fats float as top layer (gastric lipase?) Pancreas - pancreatic lipase releases fat digesting enzymes, free fatty acids and glycerol in small intestine - fat triggers release of bile and emulsifies fats |
|
|
Absorption of fats |
98% through intestinal villi |
|
|
Transport of short chain fatty acids |
Glycerol - (cells->blood->liver) |
|
|
Transportation of larger lipids |
transported by lipoproteins (lipids + proteins) and released into lymph -> blood |
|
|
Transportation of even larger lipids and long chain fatty acids |
Re-formed into triglycerides and formed with protein and phospholipids as chylomicrons |
|
|
3 Kinds of Lipoproteins |
LDL - Low-density lipoproteins (transports cholesterol + lipids to tissues) HDL - high-density lipoproteins (transports cholesterol and phospholipids away from body cells to liver cells for disposal VLDL - carry triglycerides and other lipids made by liver to body |
|
|
Chylomicrons |
Protein and lipids clusters - emulsifiers Body extracts triglycerides they need from chylomicrons passing by in bloodstream -> remnants sent back to liver |
|
|
Invisible fats in the diet |
Marbling, processed meats, fats in foods |
|
|
Added/visible fats in the diet |
salad dressing, shortenings |
|
|
Canadian standards for fats in meats |
Extra lean ground (>10%), lean (>17%), medium(>23%), regular (>30%) |
|
|
Fats in different meats |
Poultry - dark meat, under skin Fish - healthy fats/low in fats |
|
|
Fats in milk products |
Milk/yogurt - saturated *Trace amounts of fat always left to absorb vitamin D in milk products Cheese - greatest contributor of saturated fat |
|
|
Fats in grains |
very low, may be added |
|
|
Usefulness of fats in foods |
Nurtient - Fatty acids Energy Transport vitamins and phytochemicals Raw materials for other things Sensory appeal Stimulates appetite Satiety Texture - more tender |
|
|
Major risk factors for cardiovascular disease |
Non-modifiable (genetics) -> family history, older age, male Modifiable (lifestyle) -> high blood LDL-C, low blood HDL-C Artherogenic diet - high in saturated fats Physical inactivity, smoking Diabetes, obesity |
|
|
How to lower LDL-C |
Reduce saturated fatty acids, trans fatty acids, increase monounsaturated fatty acids and polyunsaturated fatty acids Limit addition of butter, sour cream, salad dressing Cook with little or no added fat Ensure adequate intakes of dietary antioxidants (vitamin C, E, selenium, phytochemicals) |
|
|
DRI for total fat |
20-35% daily calories from fat |
|
|
Recommendation for cholesterol |
Choose an adequate overall diet low in fat |
|
|
DRI's for unhealthy fats |
Saturated fats -> >10% trans fat: No DRI - just don't |
|
|
DRI's for healthy fats |
Polyunsaturated fatty acids - consume more monounsaturated fatty acids
|
|
|
DRI's for omega fatty acids |
Omega-6 fatty acid -> 5-10% Omega -3 fatty acid -> 6-12% |
|
|
Mediterranean diet |
High in grains and fibre, fruits and veggies, legumes low in saturated fatty acids, high in monounsaturated fatty acids Very low in trans fatty acids Moderate in milk and milk products, and alcohol Low in meat and meat products |
