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;
248 Cards in this Set
- Front
- Back
What are the three basic carbohydrates?
|
Sugars, Starches, Fiber
|
|
Carbohydrates formula?
|
(CH2O)n
|
|
Simple Carbohydrates?
|
Monosaccharides
Disaccharides |
|
Complex carbohydrates?
|
Polysaccharides (starch)
Fiber Glycogen |
|
Complex carbohydrates dietary sources?
|
Polysaccharides (starch)
Fiber |
|
Monosaccharides?
|
Glucose
Fructose Galactose |
|
Monosaccharides chemical structure?
|
(C6H12O6)
|
|
What does hexose mean?
|
Monosaccharides are ring structures that contain SIX carbon atoms within each molecule.
|
|
How many bonds can hydrogen form with other atoms?
|
Hydrogen can form 1 bond.
|
|
How many bonds can oxygen form with other atoms?
|
Oxygen can form 2 bonds.
|
|
How many bonds can nitrogen form with other atoms?
|
Nitrogen can form 3 bonds.
|
|
How many bonds can carbon form with other atoms?
|
Carbon can form 4 bonds.
|
|
Properties of Glucose?
|
- not very sweet
- one of two sugars in all three disaccharides - dextrose or blood sugar -essential energy source |
|
Properties of Fructose?
|
- Sweetest sugar
-component of sucrose -levulose, "fruit sugar" - sources: honey, fruits, high fructose corn syrup |
|
Properties of Galactose?
|
-not sweet
-seldom found "free" in nature -usually bound with glucose to form lactose |
|
What is a disaccharide?
|
Pair of monosaccharides.
Glucose is a component of all three. Formed by condensation. Broken apart by hydrolysis. |
|
Three disaccharides?
|
Maltose.
Sucrose. Lactose. |
|
Maltose
|
glucose + glucose
|
|
sucrose
|
glucose + fructose
|
|
lactose
|
glucose + galactose
|
|
What is a condensation reaction?
|
Reactions in which two reactants combine to form a larger product
|
|
What happens in a condensation reaction?
|
Hydroxyl group (-OH) from one monosaccharide combines with hydrogen atom from another monosaccharide.
Water is formed. Synthesis reaction. |
|
What is a hydrolysis reaction?
|
Reaction in which a molecule is split in two.
|
|
What process are hydrolysis reactions a major part of?
|
Process of digestion
|
|
What happens in a hydrolysis reaction?
|
A hydrogen atom from water is added to one molecule and a hydroxyl group is added to the other molecule.
Water is required for all hydrolysis reactions. |
|
Examples of sucrose
|
table sugar, powdered sugar, brown sugar, syrups
|
|
What enzyme breaks down sucrose?
|
Sucrase
|
|
What is lactose?
|
Milk sugar
|
|
What enzyme breaks down lactose?
|
lactase
|
|
What is lactose intorlerance?
|
People do not make lactase and have trouble digesting (hydrolyzing) lactose in dairy foods
|
|
Lactase deficiency?
|
Lack of lactast enzyme
|
|
What is a milk allergy?
|
An immune reaction to protein (casein) in milk.
|
|
Lactose Intolerance symptoms?
|
Lactose in small intestine remains undigested. Attracts water causing bloating, diarrhea, abdominal discomfort
|
|
Treatment of Lactose Intolerance?
|
Eat small amounts of milk/dairy with other foods.
Fermented milk products. Enzyme drops. "Lact-aid milk" |
|
What is "lact aid" milk?
|
Milk with lactase enzyme added to milk. naturally occuring lactose is converted into glucose and galactose.
|
|
Maltose is an intermediate product of...
|
starch breakdown
|
|
Where is maltose found?
|
Germinating seeds (bean sprouts/ alpha sprouts) and as malt
|
|
Maltose is a substrate for fermentation process that yields...
|
alcohol in beverages and breadmaking
|
|
Polysaccharide?
|
many glucose units condense together (hundreds)
|
|
Oligosaccharide?
|
3-10 glucose units
|
|
Types of polysaccharides?
|
Glycogen.
Starch. Fiber. |
|
Polysaccharide food sources?
|
Starch and fiber.
|
|
What is starch?
|
Plant polysaccharide.
Storage form of energy (glucose) in plants. Long branched/ unbranched glucose chains. major food energy source. |
|
What is glycogen?
|
Animal polysaccharide.
Storage form of carbohydrate found in muscle and liver. (1200-1400 kcals) Highly branched chains- rapid hydrolysis |
|
What is fiber?
|
only in plany foods.
polysaccharide not digestible by human enzymes. (some digested by GI tract bacteria) |
|
Fiber includes?
|
pectins, cellulose, hemicelluloses, gums, mucilages
|
|
Fiber that is a non-polysaccharide
|
Lignin
|
|
Fiber benefits and amount in diet?
|
Provide GI and cardiovascular benefits.
20-35 gms/day |
|
Why is fiber indigestible?
|
Humans lack enzyme to break the bond
|
|
What acid is often found in fiber?
|
Phytic Acid
|
|
Phytic acid?
|
nonnutrient found in grain husks, legummes, seeds.
capable of binding minerals excreted by the body. |
|
Minerals excreted by the body?
|
zinc, iron, calcium, magnesium, copper
|
|
What is insoluble fiber?
|
Not water soluble. Non viscous. Not readily fermintable by GI bacteria
|
|
Food sources of insoluble fiber?
|
Wheat bran, whole grain, brown rice, fruits, vegetables
|
|
Action in body/Health Benefits of Insoluble fiber?
|
Exercises GI muscles to speed up passage of GI contents
|
|
What is soluble fiber?
|
Dissolves in water to form gel. Viscous. Fermentable. Slow passage of food through upper GI tract. Holds moisture in stools
|
|
Food sources of soluble fiber?
|
Legumes, oats, fruits (citrus), vegetables
|
|
Action in body/ Health benefits of soluble fiber?
|
Forms gel in small intestine containing dissolved glucose and cholesterol/ bile and yields health benefits in vascular system
|
|
Benefits in vascular system due to soluble fiber?
|
Slows glucose absorption.Binds with bile/ cholesterol
|
|
Where are carbohydrated digested?
|
mouth, small intestine, pancreas, large intestine
|
|
Mouth in carb digestion
|
salivary amylase begins starch digestion
|
|
stomach in carb digestion
|
No CHO digestion because HCl inactivates salivary enzymes.Fiber is not digested in stomach but lingers delaying gastric emptying, promoting a feeling of fullness
|
|
Small intestine in carb digestion
|
maltase, sucrase, lactase
hydrolyze disaccharides |
|
pancreas in carb digestion
|
pancreatic amylase.
secreted into small intestine; digests remaining starch to individual monosaccharide units |
|
Large intestine in carb digestion
|
Viscous fibers- fermented into water, gas, short chain FAs
|
|
Viscous fibers action?
|
hold water, regulates bowel activity, cause excretion of bound bile, cholesterol, and some minerals
|
|
Within 1-4 hours after a meal what is digested and what is undigested?
|
Disaccharides and complex carbohydrates have been digested.
Fibers remain undigested. |
|
End-products of carbohydrate digestion?
|
glucose, fuctose, galactose
|
|
glucose and galactose is absorbed?
|
by active transport
|
|
fructose is absorbed by?
|
facilitated diffusion
|
|
All three monosaccharides (glucose, galactose, and fructose) are absorbed...
|
from the small intestine to the vascular system (portal vein) to the liver
|
|
In monosaccharide absorption what occurs in the liver?
|
Fructose and galactose are converted to glucose
|
|
The liver pumps glucose to?
|
into general circulation
|
|
What happens to glucose in carbohydrate metabolism after a meal?
|
Blood glucose rises and liver cells link glucose molecules together by condensation reactions
|
|
What is the livers function in carbohydrate metabolism?
|
Thel iver stores 1/3 body's total glycogen and releases glucose into the bloodstream
|
|
What occurs when blood glucose falls?
|
The liver hydrolyzes glycogen into single molecules of glucose and releases glucose into bloodstream.
|
|
What is used as fuel during exercise?
|
Muscle cell glycogen (2/3 total body glycogen)
|
|
What is the total energy available from glycogen?
|
1200-1400 kcals
|
|
What are preferred fuels for most of body's cells?
|
glucose and fat
|
|
When glucose broken down for energy what is it broken down to and what is released?
|
broken down to CO2 and H2O.Heat is released
|
|
How long do kcals from glycogen last?
|
only a few days
|
|
What happens when dietary carbohydrate is not supplied and glycogen is depleted as in starvation?
|
Problem because cells of the brain, CNS, and RBCs prefer/require glucose as energy source
|
|
Glucongeogenesis?
|
synthesis of glucose from non-carbohydrate sources (protein or fat)
|
|
What in the body is glucongeogenesis?what percent?
|
Body protein (50%)
|
|
What percent of body fat is gluconeogenesis?
|
5%
|
|
What happens when a person does not replenish glycogen stores by eating carbohydrates?
|
Body proteins are dismantled to make glucose for brain, CNS, and RBCs
|
|
Protein sparing action?
|
action/role of carbohydrate (and fat) in providing energy so protein is spared
|
|
Ketone bodies?
|
product of the incomplete breakdown of fat that occurs in gluconeogenesis when glucose is not available
|
|
Ketosis
|
fat fragments combine with ketone bodies which accumulate in blood making it more acidic
|
|
The body needs atleast how much carbohydrates/day?
|
50-100 gms
|
|
After a meal what steps occur in carbohydrate metabolism?
|
Dietary carbohydrates are digested, monosaccharides are absorbed, liver converts fructose and galactose to glucose, glucose is released from liver, blood glucose concentration rises
|
|
What does glucose entering the bloodstream condensed into glycogen replenish?
|
Replenishes glycogen stores in liver and muscle
|
|
Excess glucose is converted into...
|
fat by the liver and stored in body fat leading to obesity
|
|
Homeostasis?
|
maintenance of constant internal conditions by the body's control systems
|
|
Blood glucose?
|
regulates hormones
|
|
Hormones regulated by blood glucose levels?
|
Insulin (lowers glucose)
Glucagon (raises glucose) Epinephrine (adrenaline) (raises glucose quickly) |
|
What is insulin?
|
a hormone secreted by the beta cells of the pancreas
|
|
Insulin is secreted by the pancreas in response to?
|
Increased glucose
|
|
Primary role of insulin?
|
Control the transport of glucose from the blood stream into muscle and fat cells
|
|
Net effect of insulin is to?
|
Lower glucose
|
|
What is glucagon?
|
a hormone secreted by the alpha cells of the pancreas
|
|
Glucagon is secreted by pancreas in response to?
|
Low glucose
|
|
Primary role of glucagon?
|
Cause the release of glucose from liver glycogen stores
|
|
Net effect of glucogon?
|
Raise glucose
|
|
When is epinephrine released?
|
When a person experiences stress
|
|
What does epinephrine do?
|
Acts quickly to cause the liver to release glucose from glycogen stores into the bloodstream to ensure all body cells have an energy fuel for emergencies
|
|
Epinephrine is called the ______ hormone?
|
fight - or - flight
|
|
-emia
|
"in the blood"
|
|
-uria
|
"in the urine"
|
|
hyper-
|
"an elevated concentration of"
|
|
hypo-
|
"too low a concentration of" or "an abnormally low concentration of"
|
|
normo
|
"a normal concentration of"
|
|
normoglycemia?
|
70-110 mg/ dl glucose
|
|
Two types of diabetes?
|
Type 1
Type 2 |
|
Type 1 diabetes
|
IDDM. failure/lack of insulin production
|
|
Type 2 diabetes
|
NIDDM. Obesity. Ineffectiveness of produced insulin
|
|
What does sugar cause?
|
Dental caries
|
|
Diets that include whole grains, fibers, vegetables, legumes, and fruits provide what kind of benefits?
|
Decrease heart disease and diabetes,and colon cancer. GI health. Weight management
|
|
How much of diet should be complex carbs?
|
48%
|
|
ADA recommends how many grams of complex carbs?
|
20-35 gms dietary fiber
|
|
What sweetner gives warning to people with PKU?
|
Apartame
|
|
Phenylketonuria (PKU)
|
genetically inherited disease.
homozygous dominant=no PKU heterozygous people = asymtomatic homozygous recessive= have PKU |
|
Health people have enzyme to breakdown phenylalanine into
|
tyrosine
|
|
What occurs in people with PKU?
|
No enzyme is produced, no tyosine is produced, phyenylalanine is built up
|
|
Lipids
|
lipids are a family of compounds characterized by their insolubility in water
|
|
Lipids include:
|
TriglyceridesPhospholipidsSterols
|
|
Triglycerides
|
Fats and Oils
|
|
TGYs fats
|
solid at room tempearature
|
|
TGYs oils
|
liquid at room temperature
|
|
Phospholipids
|
lecithin
|
|
sterols
|
cholesterol
|
|
Lipids in food?
|
95% triglycerides stored in body
99% triglycerides |
|
Roles of fat in the body
|
-chief form of stored energy (starvation/fasting)
-energy for muscular work -component in cell membrane -protects internal organs -raw materials for synthesis of many compounds |
|
Roles of fat in diet
|
-concentrated energy
-carrier of fat soluble vitamins and aid abosorption -essential fatty acids -palatability of foods (taste and smell) -slows digestive process -contributes to satiety |
|
What are basic lipid units?
|
Fatty acids
|
|
What are fatty acids?
|
-organic compounds
-composed of C chains with -H attached -Acid group (COOH) attached at one end of C chain -Methyl group (-CH3) attached at other end |
|
Saturated Fatty acid?
|
18 carbon saturated fat;
stearic acid; |
|
Monounsaturated fatty acid
|
Oleic acid: 18 C; includes Omega carbon; saturated or unsaturated FA
|
|
Polyunsaturated Fatty Acid
|
Linoleic acid: 18 C polyunsaturated; saturated or unsaturated FA; Omega Family
|
|
Chemists shorthard to describe # carbon atoms and # double bonds (lipid shorthand nomenclature)
|
Examples:
stearic acid: 18:0 Oleic acid: 18:1 Linoleic acid: 18:2 Linolenic acid: 18:3 |
|
Omega Nomenclature in FAs
|
possible to identify position of first C=C relative to methyl end
|
|
what is the omega carbon atom?
|
carbon atom in the methyl group (-CH3) at one end of the FA
|
|
What is the omega number?
|
The position of the first C=C relative to the methyl end
|
|
A PUFA with its first double bond three carbons away from methyl end is...
|
omega 3 FA
|
|
Why is there an even number of carbon in a fatty acid chain length?
|
When FAs are hydrolyzed in digestion, broken apart into 2-C segments
|
|
Long chain fatty acids
|
12-24 CMeat and FishOlive Oil
|
|
Medium Chain FAs
|
6-10 Ccocoa butter and palm oil
|
|
Short chain FAs
|
less than 6 CDairy products
|
|
Degree of Saturation:Saturated FAs
|
Fully loaded with HNo C=CButter, lard and palm/coconut oils
|
|
Degree of Saturation:Polyunsaturated FAs
|
2 or more C=CLinoleic acid (18 C with 2 C=C)Linolenic acid (18 C ; 3 C=C)Vegetable oils
|
|
Degree of Saturation:Monosaturated FAs
|
1 C=COleic acid (18 C with 1 C=C)Olive oil, canola oil, peanuts/peanut oil
|
|
Double bond is the point of
|
unsaturation
|
|
Chemical structure of tryglicerides
|
95% of lipids in foods99% of lipids in bodycomposed of 3 TGYs linked onto glycerol backcone
|
|
Glycerol + 3 fatty acids =
|
Trygliceride + 3 water molecules
|
|
- H from glycerol and hydroxyl group (-OH) from FA =
|
H2O (byproduct)
|
|
What does "mixed" tryglyceride mean?
|
The fatty acids are of different makes. Some may contain double bonds.
|
|
firmness: more saturated =
|
more solid
|
|
oils generally liquid; exception:
|
cocoa butter and palm oil (saturated FAs)
|
|
Oxygen causes
|
rancidity
|
|
PUFA spoil
|
most rapidly
|
|
Saturated more resistant to:
|
oxidation/rancidity
|
|
Preventing rancidity:
|
seal/refrigerate, add antioxidants or add H to change unsaturated FA to saturated FA (hydrogenation)
|
|
Hydrogenation?
|
a chemical process by which hydrogens are added to monounsaturated or polyunsaturated FAs to reduce to number of double bonds (fat becomes more solid)
|
|
Advantages to hydrogenation?
|
Protect against oxidation (extend shelf life)
Change texture (vegetable oil--shortening) |
|
Hydrogenation disadvantage?
|
PUFA become more like saturated FAs - health advantages of PUFAs gone
|
|
Hydrogenation produces:
|
trans-fatty acids
|
|
change of shape from cis-FAs to trans-FAs
|
increased risk of CVD
|
|
Phospholipids (emulsifying agents) consist of:
|
Glycerol backbone, 2 FAs, 1 Phosphate group and N containing compound
|
|
Fatty acids in phopholipds
|
fat soluble end
|
|
phosphate group in phospholipids
|
water-soluble ends
|
|
constituent of cell membranes in phospholipids
|
helps lipids move back and forth across cell membrane into watery fluids on both sides
|
|
phospholipids are good emulsifying agents because:
|
fat soluble and water soluble ends help dissolve fats in watery medium
|
|
phospholids are used as emulsifiers in
|
the food industry
|
|
phospholipids are found naturally in:
|
egg yolk, peanuts, wheat ger, liver, and soybeans
|
|
sterols compounds with:
|
multi-ring structure
|
|
sterols multi ring structure includes:
|
cholesterol, vitamin D, bile, sex hormones, and adrenal hormones
|
|
cholesterol is both:
|
endogenous and exogenous
|
|
Cholesterol is found only in:
|
animal foods
|
|
Essential fatty acids:
|
linoleic acid
linolenic acid |
|
Linolenic acid
|
omega 3 FA
-oils -nuts and seeds -vegetables (soybeans) |
|
Linoleic Acid
|
omega 6 FA
-vegetable oils -poultry fat |
|
essential FAs can produce non-essential FAs by undergoing:
|
desaturation
elongation |
|
desaturation
|
addition of double bonds
|
|
elongation
|
lengthening of C chain by 2 carbons
|
|
essential fatty acids must make up
|
3% of daily energy intake
|
|
Who is at risk for essential FA deficiencies?
|
Premature infants, infants/ young children fed fat-free milk/ low fat diets
|
|
Essential FA deficiency symptoms?
|
skin lesions and growth retardation
|
|
Challenge with digestion, absorption and transport of lipids?
|
Fats are hydrophobic and enzymes to digest fats are hydrophilic
|
|
Where is the major site of lipid digestion/hydrolysis?
|
small intestine
|
|
Goal of lipid digestion?
|
to hydrolyze TGYS into monoglycerides, free fatty acids, and glycerol
|
|
mouth in lipid digestion
|
hard fats melt, lingual lipase (only small amount in adulthood, more in infancy due to large intake of fat)
|
|
stomach in lipid digestion
|
gastic lipase (only small amount in adults, little fat digestion)
muscle contractions disperses fat into smaller pieces |
|
small intestine in lipid digestion
|
fat triggers CCK release: gallbladder releases bile
lipases made by small intestine and pancreas act to digest lipids |
|
lipid digestion
|
in small intestine, bile emulsifies fat prior to fat hydrolysis
|
|
emulsification of fat by bile: in the stomach
|
fat and watery GI juices seperate.
|
|
emulsification of fat by bile when fat enters the small intestine
|
the gallbladder secretes bile.
|
|
Bile in emulsification of fat
|
has affinity for both fat and water, can bring fat into water
|
|
Biles emulsifying actions:
|
convert large fat golublets into small droplets that repel each other
|
|
After emulsification of fat by bile:
|
enzymes have easy access to the fat droplets
|
|
triglyceride hydrolysis
|
triglyceride and two molecules of water are split, and pieces combine to give two fatty acids and a monoglyceride
|
|
monoglyceride and 2 fatty acids from TGY hydrolysis:
|
pass into intestinal cells, but sometime will split more
|
|
lipid absorption:small digested lipids
|
absorbed directly into vascular system
|
|
lipid absorption: larger lipids (long chain FAs, monoglycerides, and fat-soluble vitamins)
|
absorbed into lymphatic system and then into vascular system
|
|
absorption of small lipids: short and medium chain fatty acids
|
water soluble enough to be absorbed from intestinal cells directly into vascular system
|
|
absorption of larger lipids: monoglycerides and long chain FAs
|
-not water soluble to be directly absorbed by vascular system-merged into micelles which enter intestinal mucosal cells-inside intestinal cells reassembled into new TGYs-packaged w. cholesterol, phospholipids and proteins into chylomicrons
|
|
micelles
|
emulsified fat droplets containing bile, monoglycerides, long-chain FAs
|
|
chylomicrons
|
what new TGYs are packaged into with cholesterol, phospholipds and proteins
|
|
chylomicrons are absorbed
|
into lymphatic system, thoracic duct (near heart) , vascular system
|
|
After bile has emulsified fat in small intestine: two destinations (enterohepatic circulation)
|
1. reabsobed from distal end of small intestine (jejunum) into vascular system; recycled back through liver and gallbladder
2. Bile trapped in soluble fiber in large intestine, excreted from body |
|
lipoproteins
|
clustersof lipids and proteins that serve as transport vehicles for fats in lymphatic and vascular systems
|
|
placement of phospholipids and proteins ; TGYs and cholesterol in lipoproteins
|
phos. and proteins (hydrophilic)- located outside
TGY and cholesterol (hydrophobic)- located inside |
|
how do lipoproteins differ?
|
by size, density, and amounts of lipid/protein compenents
|
|
lipoprotein chylomicrons
|
largest, least dense (>80% TGY) made in intestinal cells
function: transport dietary lipids from intestinal cells to rest of body |
|
Very low density lipoproteins (VLDL)
|
-made in liver from chylomicron remnants
-TGY removed from VLDL, it becomes more dense, % of components change, VLDV become LDL |
|
VLDL function
|
transport lipids to various tissues of the body
|
|
Low Density Lipoproteins (LDL)
|
Derived from VLDL; composed of cholesterol; LDL=less healthy form of cholesterol (high CVD risk)
|
|
LDL function
|
circulate cholesterol throughout the body
|
|
High Density Lipoproteins (HDL)
|
smallest and richest in protein made from compenents released from fat cells (primarily cholesterol)
HDL= healthy form of cholesterol (low rish CVD) |
|
HDL function
|
transport cholesterol from cells back to liver for excretion
|
|
Where is body's primary energy source?
|
TGYs in food and body fat
|
|
where is body's fat stored?
|
adipose tissue (unlimited storing)
|
|
lipoprotein lipase (LPL)
|
hydrolyzes TGYs from circulating lipoproteins into glycerol, FFA, and monoglycerides that enter adipose cells
|
|
inside adipose cells: glycerol, FFAs, and monoglycerides are condensed into
|
TGYs
|
|
After a meal, adipose cells:
|
store fat when TGY- rich chylomicrons and VLDL pass by
(LPL required for adipose cells to store fat) |
|
Body can store how much fat?
|
unlimited amounts
|
|
fat supplies __ of energy at rest
|
60 %
|
|
hormone sensitive lipase
|
- when cells need energy
-inside adipose cells -hydrolyzes TGYs in fat cells |
|
glycerol and FFAs enter blood
|
and are used as fuel source of cells throughout the body
|
|
1 lb body fat =
|
3500 kcals
|
|
If fasting person expends 1750 kcals/day will lose half body fat/day?
|
NO
|
|
How much energy needed for brain, cns, and rbcs?
|
1/3
|
|
if in prolonged fast, brain and nerve cells derive energy from where?
|
2/3 of energy from ketone bodys (fat broken down for energy) BAD
|
|
humans have no excess ____ and ____ for energy?
|
proetins/ proteins stores
|
|
what kind of person will survive longer during a forced starvation?
|
a person with more body fat
|
|
Relationship between dietary lipids and heart disease?
|
raised cholesterol major CVD risk factor (animal in orgin)- not as much as saturated fats/trans fat; HDL vd LDL
|
|
Risks from saturated fats?
|
raise LDL- increases CVD risk
animal in orgin |
|
Risks from trans fat
|
raise LDL; increased CVD risk
|
|
benefits from monounsaturated fats
|
decreases CVD risk;
lowers rate of heart disease (olive oil) |
|
benefits from polyunsaturated fats
|
lowers cholesterol; reduces CVD risk but increases cancer risk
|
|
benefits of omega 3 fats
|
decreases CVD risk, prevent blood clots, lowers blood pressure (food not supplements)
|
|
relationship between dietary fats and cancer
|
doesnt initiate cancer but does promote. total kcal and obesidy better implyers.
fat from meat more associated with cancer |
|
relationship between dietary fat and obesity
|
fat contributes 2X many kcals as carbs or protein
|
|
fat recommendations
|
total fat <30%
sat fat <10% reduce trans fat reduce cholesterol (300mg/day) eat more omega 3 |
|
fat replacers
|
carbohydrates/ proteins that replace some/all of the fat in foods lowers kcals
|
|
artificial fat
|
olestra
|
|
olestra
|
made of sucrose and FAs
|
|
Humans and olestra
|
humans dont make enzyme to digest; 0 kcals;
|
|
olestra physical properties
|
like fat; may cause abdominal distress; binds with fat soluble vitamins resulting ing excretion additionsl Vit A,D,E,K added to snack foods
|