Mid Term #2 Flashcards
Fill in the blank:
Triglycerides are the most common lipid found in food and in the body; they consist of a ______ backbone attached to three fatty acids.
Glycerol
Fill in the blank:
Fatty acids are classified based on the degree to which the carbon chain is saturated with _______.
Hydrogen
Fill in the blanks:
A fatty acid is _______ if it contains no carbon-carbon double bonds, _________ if it has only one carbon-carbon double bond, and __________ if it contains two or more carbon-carbon double bonds.
- Saturated
- Monounsaturated
- Polyunsaturated
The unsaturated fatty acids can exist in one of two structural forms. What are they?
Cis:
- Hydrogens=same side of the carbon-carbon double bond
Trans:
- Hydrogens=double bond lie on opposite sides of the bond.
Are lipids enzymes?
no
What are the three things that lipids do?
- Store energy
- Insulate
- Part of cell membranes.
What does fat add directly to a meal?
Enticing flavor and aroma
What does the mouth do in fat digestion?
Saliva minor digestion of fat
What does the stomach do in fat digestion?
Minor fat digestion by gastric lipase.
What does the small intestine do in fat digestion?
Site of most fat digestion and absorption.
What does the liver do in fat digestion?
Secretes bile to emulsify fats.
What does the pancreas do in fat digestion?
Secretes pancreatic lipase and other enzymes for fat digestion.
Fill in the blank:
The salivary glands, stomach, and pancreas secrete _______ enzymes to break down triglycerides into monoglycerides, fatty acids, and glycerol.
Lipase
Fill in the blank:
The products of fat digestion (monoglycerides, fatty acids, and glycerol) are absorbed into the cells of the _________.
Small intestine
Fill in the blank:
Immediately after absorption, the products of fat digestion are resynthesized into triglycerides within the cells of the ________.
Small intestine
What are Chylomicrons?
Before they can be transported through body fluids, dietary lipids must be packaged as lipoproteins
What is the Lymphatic system?
These lipoproteins are absorbed from the gastrointestinal tract into the vessels of the lymphatic system.
Fill in the blank:
The liver secretes ______ to emulsify fats in the chyme in the small intestine.
Bile
What carries absorbed lipids from the small intestine to body cells?
Chylomicron
What arises from VLDL and carries mostly cholesterol to the cells?
LDL
What is VLDL?
Carries to body cells mostly triglycerides taken up from the bloodstream by the liver as well as any fat made by the liver.
What is HDL?
- Arises mostly from the liver and intestine
- Carries cholesterol from cells to other lipoproteins and to the liver for excretion.
What should the recommended fat intake?
20-35%
What is considered an essential fatty acid?
Linoleic acid
Fill in the blank:
Olive oil contains mostly ______ fatty acids.
Monounsaturated
What is a food that is cholesterol free?
Peanut butter
Which combination of foods provide the best source of omega-3 fatty acids?
Carrots and snow peas stir-fried in canola oil.
What food is the best source of EPA and DHA?
Fatty fish
Is it higher or lower?
Coconut oil is ________ in saturated fatty acids than butter and beef fat.
Higher
What do Omega-3 fatty acids tend do to blood clotting?
Decrease
What do Omega-3 fatty acids do to inflammation in the body?
Decrease
What does Omega-6 fatty acids do to clotting and inflammation in the body?
Increase to both
What do omega-3 fatty acids as a dietary supplement do to circulating triglyceride levels in the blood?
Decrease
Fill in the blank:
Fish oil capsules are associated with a(n) ________ in rheumatoid arthritis symptoms and some behavioral disorders and cases of mild depression.
Decrease
What is NOT a component of plaque?
Chylomicron
What are the three components of plaque?
- Oxidized LDL
- Platelets
- Calcium
What are some components of an anti-atherosclerotic lifestyle?
- Smoking cessation
- Engaging in daily physical activity
- Dietary pattern low in saturated and trans fats
- Dietary pattern high in fruits and vegetables
Which of the following individuals would be at highest risk for cardiovascular disease?
50-year-old man; Abdominal obesity; HDL-C = 39 mg/dl
Besides her fat intake, what other dietary modifications could improve Jackie’s heart health?
Choose whole grains instead of refined grain products.
What are the functions of lipids?
- Energy use and storage
- Insulation and protection
- Hormone synthesis
- Nerve impulse transmission
- Component of absorbing vitamins
- Nutrient transport
What makes up Triglycerides?
- Fatty acids
- Glycerol
What makes up sterols?
Cholesterol
What are fatty acids?
- String of carbons
- Methyl group one end, acid group other end
- Differ in number and position of types bonds
What is Triglyceride makeup?
Glycerol backbone + three fatty acids
What is Monoglyceride makeup?
Glycerol + 1 fatty acid
What is Diglyceride makeup?
Glycerol + 2 fatty acids
What are saturated fats?
Properties:
- 0 double bonds
- Carbon chain completely filled with hydrogen
Food sources:
- Animal fats
- Tropical oils like coconut oil
Health implications:
- High intake may increase risk for CVD
What are Monounsaturated fats?
Properties:
- 1 double bond
Food Sources:
- Olive and canola oils
- Avocado
- Peanut butter
Health implications:
- May decrease risk for CVD
What are Polyunsaturated fats?
Properties:
- Two or more double bonds
Food sources:
- Plant oils
- Fatty fish
- Nuts
Health implications:
- Depends on the type (omega 3 most heart-healthy)
What is Linoleic acid?
- omega-6 fatty acid family
- Food sources: plant oils, margarine, mayonnaise
What is Linolenic acid?
- omega-3 fatty acid family
- Food sources EPA +DHA: In plants ALA: canola oil, flax, walnuts
What are the benefits of Omega-3?
- Lower blood pressure
- Prevent blood clot formation (large amounts may cause bleeding, bruising)
- Protect against irregular heartbeats
- Reduce blood triglyceride levels
- Brain vision function (especially in infants)
What is the maximum amount of fish you should eat?
Limit fish to 12 oz/week
What is cholesterol?
- Produced by liver
- Used to make hormones, bile acids, and Vitamin D
- No energy
- Food sources: ONLY in animal products (even healthy ones)
What are the main cause of increases in cholesterol?
Saturated fat and trans fat are the main culprits for raising blood cholesterol
What are Phospholipids?
- Glycerol + 2 fatty acids + phosphate
- Form structure for cell membranes
What are the 3 parts of Lipid Absorption?
- Bloodstream
- Turn into triglycerides
- Transported via chylomicrons in the lymphatic system
What are the four things that participate in cholesterol/lipid transport lipoproteins?
4 kinds:
- Chylomicrons: dietary fat transporters
- VLDL (very low density lipoprotein): fat deliverers
- LDL (low density lipoprotein): cholesterol deliverers
- HDL (high density lipoprotein): cholesterol clean up crew
What is Atherosclerosis and Plaque Process?
Atherosclerosis:
- Foam cells form a fatty streak and calcify
- Narrowed arteries are at-risk for clots
Plaque Process:
- Minerals, platelets, and oxidized LDL form plaque
What is the diet to reduce the risk of heart disease?
- Low in saturated, trans fats, sugar, and refined grains
- High ratio of omega 3:omega 6
- Lots of plant-based foods
What heart rate should you keep it below to reduce risk of heart disease?
<90/<60
What are the healthy lipid levels for cholesterol, LDL, HDL, and Triglycerides?
- Total blood cholesterol <200
- LDL <100
- HDL >60
- Triglycerides <100
What is Hydrogenation?
- The process that adds hydrogens to unsaturated fat to increase its shelf life
- Results in a trans fat
What is the recommended fat intake?
- AMDR 20%-30% calories from fat
- Consume <10% of calories from saturated fat
- Consume fish twice a week
Reminder: Benefits of Omega-3
- Lower blood pressure
- Prevent blood clot formation (large amounts may cause bleeding and bruising)
- Protect against irregular heartbeats
- Reduce inflammation
The chemical element found in all amino acids but not found in either carbohydrates or fats is what…..?
Nitrogen
Which part of the chemical structure differentiates one amino acid from another?
Side Chain
Protein synthesis is a multistep process. Put the steps of protein synthesis in sequential order.
- The DNA code is transferred by mRNA from the nucleus to the cytoplasm of a cell.
- Messenger RNA (mRNA) carries the DNA code to the ribosomes, where protein translation occurs.
- Transfer RNA (tRNA) adds amino acids one at a time according to the mRNA instructions to form a polypeptide chain.
- Polypeptide chain twists and folds into three-dimensional structure of the intended protein.
In protein digestion what does the liver do?
The portal vein delivers absorbed amino acids to this organ, where they then go on to enter the bloodstream
In protein digestion what does the stomach do?
Where pepsin and acid work to digest protein
In protein digestion what does the pancreas do?
Triggered by CCK, this organ releases trypsin for the digestion of proteins
In protein digestion what does the small intestine do?
Final digestion of amino acid chains to single amino acids occurs in the walls of this organ
In protein digestion what does the large intestine do?
Very little protein is present in the feces by the time it reaches this part of the large intestine
How can amino acids be used in cells?
Converted to nonessential
The nitrogen from amino acid breakdown is converted to what?
Urea
What happens to protein synthesis when an essential amino acid is in short supply?
Protein synthesis is limited.
What are the functions of protein in the body?
- Supports immune response
- Structure
- Synthesis of Hormones & Enzymes
Edema appears when there is a severe lack of dietary protein because of what?
Blood protein levels fall, and fluid shifts into extracellular spaces.
What are some examples of high quality protein?
- Milk
- Eggs
- Chicken
Difference between positive, negative and equilibrium for protein balance.
- Positive protein balance occurs when the body is recovering after illness or injury or when the body is growing.
- Negative protein balance describes a situation in which protein intake is less than protein requirements. Negative protein balance can occur during acute illness, which reduces the desire to eat.
- Protein equilibrium exists when protein intake equals protein losses. For healthy people, the amount of dietary protein needed to maintain protein equilibrium is 0.8 grams of protein per kilogram of healthy body weight: 84 kg × 0.8 g/kg = 67 grams of protein.
How many cups of protein are in dairy?
8-10 cups
How many cups of protein are in protein?
7 oz
How many cups of protein are in vegetables?
2-3 cups
How many cups of protein are in grains?
2-3 oz
How many cups of protein are in fruits?
less than one cup
The Acceptable Macronutrient Distribution Range for total protein intake is
10% to 35% of total kcal.
Alicia is a sedentary, 20-year-old woman. She weighs 145 pounds. Based on her body weight, what is her Recommended Dietary Allowance (RDA) for protein?
53 grams
The RDA for protein for adults is 0.8 grams per kilogram of body weight per day. Alicia’s weight is given in pounds, so you can convert pounds to kilograms by dividing by 2.2 lb/kg.
145 lb ÷ 2.2 lb/kg = 65.9 kg
65.9 kg × 0.8 g/kg/d = 53 g/d
When a person eats more protein than his body needs, the extra protein is
converted to glucose or fat.
When protein is converted to glucose or fat, nitrogen is eliminated from the body via what organ?
the kidneys.
What is Kwashiorkor?
- Appearance is one with swollen belly from either fatty liver or edema
- Common in you children who are weaned from breast milk to a high-starch, low protein diet
- Form of protein-calorie malnutrition that develops acutely (rapidly)
What is marasmus?
- Appearance is one with “matchstick” arms and no subcutaneous fat
- Common in infants who receive inadequate calories and protein from the beginning of life
- Form of protein-calorie malnutrition that develops graduately
Bodybuilding magazines have numerous advertisements for protein and amino acid supplements. Which of the following is a potential problem associated with taking individual amino acid supplements?
Impaired absorption of other amino acids
What would you choose as the optimal nutrition to support your weight-training regimen?
Consume a diet that provides 10% to 35% of calories from a variety of sources of protein.
Many North Americans have misconceptions about their own protein needs and the roles of protein in the body.
- Eat more plants to get more amino acids
- Americans would benefit from eating plant-based proteins
What is nutrigenetics?
- Study of the effect of genes on nutritional health
- People with different genes may respond differently to the same dietary pattern
What is nutrigenomics?
Study of how food impacts health through its interactions with genes
What is epigenetics?
Heritable changes in gene function that are independent of DNA sequence
It is apparent that Jordan has not yet learned to implement the concept of complementary proteins, so the quality of protein in his diet is low. Which of the following meals contains complementary proteins?
Rice with black beans and tomatoes
Vegan diets are often low in _______, on account of animal foods being excluded from the diet.
Vitamin B12
True or false: An omnivorous (includes animal and plant foods) diet that follows the Dietary Guidelines (MyPlate recommendations) can provide the same health benefits as a well-balanced vegetarian diet.
True
Which amino acids are important for protein synthesis?
All 9 of them
What does the stomach do during protein digestion?
- HCL denatures (opens and permanently distorts shape)
- Pepsin enzyme cleaves it into polypeptides
What does the small intestine do in protein digestion?
Splits polypeptides –> tri –> dipeptides –> amino acids.
What is protein absorption?
- Portal vein
- Amino acids can compete for absorption so aa supplements are not recommended
What is the fate of an amino acid?
- Converted into nonessential
- Used for energy
- Converted to glucose or fat
- Deamination required (nitrogen must be removed)
What is Deamination?
- Amino group removed>converted to urea>filtered by the kidneys and excreted in urine
- Remnants can be metabolized or converted to carb or fat
When protein intake is very high, we see increased urinary ______ excretion.
nitrogen
Roles of protein
- Growth and maintenance
- Immune
Roles of protein
Blood clotting
Synthesizing enzymes, hormones, other compounds
Roles of protein
Transport around the body
Fluid and electrolyte balance
Proteins in the bloodstream attract water back keeping it balanced (otherwise __edema__)
Transport proteins in cell membranes regulate what goes in and out
Roles of protein
Providing energy and glucose
Nitrogen removed>urea>excreted in urine
How to determine Protein Quality?
- Determined by amount of aa provided in comparison to our body’s need
- High-quality/complete proteins provide all 9 essential amino acids
Examples of high, moderate and low protein quality:
High:
- Animal
Moderate:
- Legumes
Low:
- Grains
- Vegetables
Protein Quality
When different, complementary low-quality/incomplete proteins are consumed within the same meal or day, protein synthesis is not limited
Grains, nuts and seeds are low in lysine
Legumes and vegetables are low in methionine
Dietary Guidelines recommend greater emphasis on __plant___ ___proteins____.
Examples of combining proteins
Bread and peanut butter + Pita and hummus
Rice and lentils + Tortillas and beans
What are the Protein requirements?
- RDA for protein 0.8 g/kg
- AMDR = 10-35% of calories
- World Health Organization 10%-15%
How much to optimizing muscle synthesis?
~20-25 g each time throughout the day
Protein And Amino Acid Supplements good or bad? Why?
Protein supplements:
- Not better than regular foods
- No level of aa supplements can be assumed safe
- Much is unknown
Important points on protein and building muscle
Those trying to gain muscle often don’t need as much protein as they think they do
Following the AMDR and MyPlate protein recs meets even high protein needs
Protein supplements, powders, and bars have a place, but often aren’t necessary and lack other nutrients that are in “real food” protein sources
Eating extra protein doesn’t build muscle. Strength training plus adequate protein and calories builds muscle
Characteristics of malnutrition
- Weight loss, slow growth
- Hair loss
- Increased susceptibility to infection
- Impaired nutrient absorption
- Impaired brain & kidney function
Examples of nutrigenetics
Nutrigenetics: HDL can go up or down with increasing consumption of PUFAs based on genotype
Example of nutrigenomics
Nutrigenomics: Supplemental B vitamins given to the mother mouse silenced the gene for yellow and fat in the baby mouse and it turned out brown and lean
Are the recommendations based on genetic testing?
No
Types of vegetarian diets
Vegan (no animal products)
Vegetarian
Lacto-ovo (dairy and eggs, but no meat)
Lacto (dairy, but no meat and eggs)
What are the benefits and limitations of vegetarian diets?
Possible Benefits
Less obesity/ chronic disease
High fiber, fruits & vegetables
Less saturated fats
Possible Limitations
Low energy for kids
Less minerals (Calcium, Iron, Zinc)
Less vit B-12 (only in __animal__ products) & Vit D
Vegetarian Diet vs. Meat Diet
Both meat-containing diets and vegetarian diets can be healthy or unhealthy depending on the food choices
Diets high in fruits, vegetables, whole grains, and lean meats can provide the same benefits seen in vegetarian diets
Basal metabolism is the largest component of total energy expenditure, typically accounting for 60% to 75% of total energy needs. Which of the following factors would decrease your basal metabolic rate?
A low calorie intake
Joe has a hectic schedule. During the day, he works full time at a warehouse distribution center filling orders. At night, three times a week, he attends class at the local community college in pursuit of computer certification. On weekends, he likes to watch sports on television, spend time with family and friends, and study. Joe has little time to exercise or think about what he eats—that is, convenience rules. He stops for coffee and a pastry on his way to work, has a burger or pizza for lunch at a fast-food restaurant, and for dinner picks up fried chicken or fish at the drive-through on his way to class. Unfortunately, over the past few years, Joe’s weight has been climbing. He is 5 feet, 10 inches tall and weighs 200 pounds. Lately, he has frequently been short of breath during his shift at work. Watching a game on television a few nights ago, he saw an infomercial for a weight-loss supplement that promises to increase his energy level and allow him to continue to eat large portions of tasty foods but not gain weight. A famous actor supports the claim that this product allows one to eat at will and not gain weight. This claim is tempting to Joe.
Joe’s body mass index (BMI) is ______ kg/m2. (Enter numeric response only; round your answer to the nearest 0.1.)
28.7
BMI = (200 lb × 703) ÷ (70 in × 70 in) = 28.7 kg/m2.
What is considered to be underweight?
Underweight is defined as BMI <18.5.
What is considered to be healthy weight?
Healthy weight is BMI 18.5 to 24.9.
What is considered to over weight?
Overweight is BMI 25 to 29.9.
What is considered to obese?
Obese is BMI ≥ 30.
How to calculate BMI?
To calculate BMI, multiply weight (pounds) by 703, then divide by height2 (inches).
Examples:
- For Brittany, (120 × 703) / (68 × 68) = 18.2 = underweight.
- For Kathy, (140 × 703) / (68 × 68) = 21.3 = healthy weight.
- For Darlene, (140 × 703) / (62 × 62) = 25.6 = overweight. - For Janice, (200 × 703) / (68 × 68) = 30.4 = obese.
Waist circumference is a measure of
Central obesity
Who has the LOWEST health risk, based on the information provided?
5’6” female, 142 pounds, waist circumference 30”
Sleep apnea
excess wight in the upper body places pressure on the lungs and pharynx
Heart disease
excess weight and enlarged adipose cells cause increases in LDL-cholesterol, triglycerides, blood clotting, and inflammatory factors.
Gallstone formation
High-fat and high-cholesterol diet increase the cholesterol content of bile.
Erectile dysfunction in men
excess wight causes inflammation and reduced function of blood vessels
Liver damage
high-fat diet and weight gain lead to excessive fat accumulation in the liver.
Quick, large changes in weight (leading to weight loss) are most likely the result of all of the following
- Changes in body fluid content.
- Changes in electrolytes and fluid balance.
Despite advertisements and fad diet promises, there is no quick solution for weight loss. Successful weight loss comes from hard work and commitment. Click to select the elements of a successful weight-loss program.
- Decrease calorie intake
- Increase physical activity
- Modification of problem behaviors
Which scenario is an example of healthy weight loss?
Denise lost 25 pounds in 6 months by following a diet that included a variety of foods, even occasionally including her favorite dessert of chocolate cake.
Calorie Balance Principle
E intake > E need E storage, weight gain
E intake < E need E depletion, weight loss
E intake = E need E balance (no weight change)
3500 calories = 1 pound of fat
Components of Energy Expenditure
Basal Metabolic Rate (BMR)
All the involuntary activities in our body needed to sustain life (except __extra energy_!)
Usually the ___largest____ component of energy expenditure
Many factors increase or decrease it
Lean body mass, aging, growth, fever, dieting, etc.
Components of Energy Expenditure
Physical activity
Voluntary activities
Most variable component of energy expenditure
Thermic effect of food
Cost of ___energy_ and absorption of nutrients
Adaptive thermogenesis
nonvoluntary physical activity triggered by reflexes (ex. shivering)
Body Mass Index (BMI)
Indicator of health risk based on body weight and height
BMI = weight (kg)
height (m)2
Easy calculation for BMI:
weight (lbs) x 703
height (in)2
BMI Calculation Tips
Determine height in inches.
Square it (multiply by itself). Write down your number.
Multiply wt in lbs by 703.
Divide by number you wrote down.
BMI limitations
Doesn’t indicate how much of weight is fat
Doesn’t indicate where that fat is located
Limited use for:
Athletes or those with very low body fat %
Pregnant and lactating women
Adults >65
Women >50 with little muscle
Who else?
Ways to assess body composition
Bioelectrical impedance
Dexa
Bod Pod
Skinfold
Underwater weighing
Fat location
Visceral fat: stored in ___belly____ and around organs, higher health risk
Excess visceral fat is called central obesity
Fat distribution is mostly determined by genetics
Measure by waist circumference
Men >40
Women>35
Health risks associated with excess body fat
Diabetes
Heart disease
Hypertension
Breast, colon, endometrial, and other cancers
Gallbladder disease and gallstones
Nonalcoholic fatty liver
Stroke
Arthritis
Sleep apnea
Health risks from too little body fat
Disadvantage in the hospital
Increased risk of death for surgical patients and those fighting wasting diseases
Lack of protection/cushion
Reproductive issues
Does “dieting” work?
Why fad diets work
Fewer calories eaten than expended
Appeal to people’s “all or nothing” mentality
Why fad diets don’t work
Cut too many calories, hunger
Restrictive
Inflexible
Short-term
Focused on fast results
Strategies for a healthy body weight
Choose right amount of calories
Get adequate nutrient intake from nutrient-dense foods (ChooseMyPlate)
Pay attention to your environment and emotions
Be consistent, but flexible (goodbye to diet mentality)
Get into the habit of being active
1) Choose right amount of calories
Eat fewer calories than burning, but not too few!
Slower weight loss=better
No more than 1-2 pounds/week
Greater loss than this is not a loss of fat. It includes loss of body fluid, lean body mass, and electrolyte changes.
Don’t eat fewer calories than your __recommended___ __daily__ __allowance_!
2) Adequate nutrient intake
Follow AMDR and ChooseMyPlate guidelines
Fruits, veggies, nuts, legumes, fish, poultry, low-fat dairy, whole grains, unsaturated fats
Choose nutrient-dense rather than energy-dense (large quantity of food low in kcals over small amount high in kcals)
3) Pay attention to your environment and emotions
Surround yourself with supportive people
Track your intake if it’s helpful
Remember, eating doesn’t solve emotional challenges
Be mindful of external eating cues and portions…
4) Be consistent, but flexible
Don’t deprive yourself. Even less healthy, higher-calorie foods can fit if…
Eaten in smaller portions
Eaten less often
Kept within ChooseMyPlate parameters
Get rid of the diet mentality. No such thing as “blowing it.” Just get right back on the wagon.
Do what works for YOU
5) Get into the habit of being active
Physical activity augments diet
For weight loss
For weight maintenance
Biggest benefit of PA is improved fitness
Definition of healthy weight loss
- Long term
- 2 pounds or less
- minimum regain
- healthy relationship with food
- Physical activity
Strategies to gain weight
Choose foods with high energy density
Drink (healthy) calories
Eat more and eat more often
Keep a supply of snacks
Increase portion sizes
Add interest to food
Include physical activities that build muscle
