Midterm #1 Flashcards
Hierarchy Of Nutrition Related Pathology
- Nutrition Plays Role - e.g. osteoporosis (related to Ca, exercise, etc.)
- Strong Nutritional Component - e.g. heart disease, stroke, diabetes, celiac
- Deficiencies/Toxicities - scury, iron deficiency, pellagra (b vitamin niacin)
Definition Of A Calorie
Heat Required To Raise Temp. Of 1 Kg Of Water 1 Degree Celsius.
Dietary Reference Intake (DRI) For Micronutrients - RDA
Recommended Dietary Allowance - first established when health care professionals were primarily concerned with deficiency disorders. Covers 97% of population from inadequacy.
Dietary Reference Intake (DRI) For Micronutrients - EAR
Estimated Average Requirement - meets requirement for 50% of the population. When enough data exists, an RDA is then established.
Dietary Reference Intake (DRI) For Micronutrients - AI
Adequate Intake - Used when RDA doesn’t exist; covers from estimated RDA at lower limit to 20% towards the upper limit.
Dietary Reference Intake (DRI) For Micronutrients - UL
Tolerable Upper Intake Level - the point where intake starts to show adverse effects. Begins at appropriately the AI maximum.
Dietary Reference Intake (DRI) For Macronutrients - EER
Estimated Energy Requirement - the average caloric intake to maintain energy balance for different populations.
Dietary Reference Intake (DRI) For Macronutrients - AMDR
Acceptable Macronutrient Distribution Ranges - range of intake for each macronutrient associated with reduced risk of chronic disease while still maintaining adequate intake of essential nutrients.
AMDR Recommendations
Carbohydrate - 45-65% of energy
Fat - 20-35% of energy
Protein - 10-35% of energy
Dietary Questionnaires
- Diet History - eating patterns, physical activity, frequency of eating out, etc.
- 24 Hour Recall - reliance on memory and estimation of portion size.
- FFQ (Food Frequency Questionnaire) - list of foods, patient records how often (s)he eats that food
- Diet Record - list over 3-7 days
Case-Control Study
More complex that epidemiological studies, but do not illustrate causation. Involve subjects from the same population (i.e. elderly men with high blood pressure.)
Clinical Trial
Level 1 - transfer from rats to humans; few people to prevent fatalities.
Level 2 - larger human subject pool; safe in humans now need larger pool to show not due to chance.
Level 3 - used to gauge dosages.
Malnutrition, Undernutrition, Overnutrition
Malnutrition - imbalance (too much of one nutrient without another)
Undernutrition - deficiency
Primary Deficiency - not enough
consumption of a nutrient.
Secondary Deficiency - cannot
absorb a nutrient.
Overnutrition - too much (i.e. obesity, toxicity)
Nutritional Assessment - ABCDE G
A - Anthropometric B - Biochemical C - Clinical D - Dietary E - Environment
G - Genetics
Nutritional Assessment - Anthropometric - General
- Percent Fat - Skinfold
- BMI
- Waist To Hip
Nutritional Assessment - Biochemical
- Urine - albumin and glucose
- Blood Glucose
- Insulin
- Others - cholesterol, triglycerides
- Homestatic Model (HOMA - IR)
- Triglyceride Index (TyG Index)
Nutritional Assessment - Clinical
Is the patient having headaches, nausea, hair falling out, etc.
Nutritional Assessment - Dietary
Usage of 24 hour recall, FFQ, diet record to determine dietary intake.
Nutritional Assessment - Envrionment
Water health, chemical plants, copper wiring, etc.
Nutritional Assessment - Genetics
Epigenetic affects on gene methylation, acetylation, phosphorylation, repression and activation, etc.
Caloric Equivalents For Macronutrients
Carbohydrate - 4 kcal/g; 5 kcal/L O2 Lipid - 9 kcal/g; 4.7 kcal/ L O2 Protein - 4 kcal/g; 4.5 kcal/ L O2 Alcohol - 7kcal/g Soluble Fiber - 1.5 - 2.5 kcal/g due to bacteria fermenting into SCFA
Components Of A Healthful Diet
- Adequate - enough energy, nutrients
- Moderation
- Balanced - many different food groups (meat, vegetables, fruits, etc.)
- Variety - different food from each food group (lettuce, peppers, kale, etc. among vegetables)
Components Of The Food Label
- Statement Of Identity - product name is prominently displayed.
- Net Contents - quantity of package
- Ingredients List - in order of weight
- Name/Address Of Manufacturer
- Nutrition Information
Nutrition Labels
- Serving Size - determine by FDA
- Calories and Calories From Fat
- Nutrient List - nutrients at top should be limited (fat, sat fat) while ones at bottom should be consumed more.
- Percent Daily Value - how much one serving contributes to the suggested overall daily intake of that nutrient.
- Footnote - if space, 2500 cal per day diet will also be included.
Manufacturer Claims - Regulated By FDA
- Nutrient Claims - based on daily values (i.e. low sodium means less that 140mg)
- Health Claims - related to health and disease.
Manufacturer Claims - Not Regulated By FDA
Structure-Function Claims - generic claims about the food’s impact on body (i.e. builds strong bones). Cannot be about a specific disease or symptom.
FDA Approved Nutrient-Related Terms And Definitions Relative Claims - Free/Without/Zero/No
None/trivial amount of that given nutrient.
FDA Approved Nutrient-Related Terms And Definitions Relative Claims - Light
- > 1/3 fewer kcal or >1/2 fat from regular food.
- > 1/2 sodium from regular food
- Lighter in color or texture
FDA Approved Nutrient-Related Terms And Definitions Relative Claims - Reduced/Less/Fewer
> 25% less nutrient or kcal than regular food.
FDA Approved Nutrient-Related Terms And Definitions Relative Claims -More/Added/Extra
> 10% of DV compared to regular food. Only used for vitamins, minerals, protein, fiber, potassium.
FDA Approved Nutrient-Related Terms And Definitions Relative Claims - Good Source Of/Contains/Provides
10-19% of DV per serving, not used for carbohydrate.
FDA Approved Nutrient-Related Terms And Definitions Relative Claims - High/Rich In/Excellent Source Of
> 20% of DV per serving (protein, vitamin, mineral, fiber, potassium, not carbohydrate).
Percent Daily Values - Total Fat, Sat. Fat, Total Carbohydrate, Fiber
Total Fat - 30%
Saturated Fat - 10%
Total Carbohydrate - 60%
Fiber - 25g
*Based on 2000 kcal/day diet
Food Pyramid
Grains Vegetables Fruits Oil Dairy Meat and Beans
Quantity Estimates - Golf Ball, Tennis Ball, Deck Of Cards, Baseball
Golf Ball - 2 tbsp
Tennis Ball - 1/2 cup
Deck Of Cards - 3 oz
Baseball - 1 cup
Layers Of GI Wall
- Mucosal - epithelial/endocrine cells
- Submucosal - connective tissue; glands, nerves, vessels
- Muscular - circular, longitudinal, oblique (oblique only in stomach)
- Serosa - connective tissue, protection
Miscellaneous Anatomy - Pharynx
Throat, passageway between mouth and esophagus. Soft palate prevents bolus from entering the nasal pharynx.
Miscellaneous Anatomy - Superior and Inferior Mesenteric Arteries
Arise from the abdominal aorta. Superior supplies SI and pancreas. Inferior supplies colon.
Miscellaneous Anatomy - Superior and Inferior Mesenteric Veins
Drain blood from GI to the liver via the portal vein. Superior drains SI. Inferior drains colon and meets superior as it meets the portal vein.
Miscellaneous Anatomy - Omentum
Sheet of fatty connective tissue that protects and holds organs in place. It is highly vascularized. This is where abdominal fat accumulates.
Miscellaneous Anatomy - Celiac Trunk Artery
One of 3 branches from the aorta (the others being super and inferior mesenteric arteries). Supplies the liver, stomach, esophagus, and superior duodenum and pancreas.
Miscellaneous Anatomy - Hepatic Artery
Branches from celiac trunk artery and supplies liver, pylorus (part of the stomach that connects to SI), and pancreas.
Miscellaneous Anatomy - Lacteals
Digestion of longer chain fatty acids collected in lacteals and enter lymph which ends at thoracic duct and is dumped into heart. SCFA enter portal vein with carbohydrate.
Digestion. Mouth. Salivary Glands
Parotid - largest, back of the mouth
Sublingual - smallest, under tongue in from of submandibular
Submandibular - middle sized, beneath jaw, between parotid and sublingual
Digestion. Mouth. Chewing and Swallowing
Chewing: epiglottis is open, breathing
Swallowing: epiglottis covers trachea, esophageal sphincter releases to open trachea.
Digestion. Mouth. Secretions. Saliva
Water Amylase - Starch to maltose Lingual Lipase - Milk, lost at age 5-6 Ca and P - Preserve ionic gradient Lysozyme - kill bacteria and viruses Antibodies - " Bicarbonate - Buffer acidity
Digestion. Esophagus. Sphincters
Upper esophageal sphincter
Lower esophageal sphincter
Digestion. Stomach. Sphincters
Pyloric sphincter empties chyme into SI in small amounts
Digestion. Stomach. Cell Types and Locations
Gastric Gland - bottom of the invaginations created by rugae, at the gastric pit.
Parietal Cells - bottom of gastric pit
Chief Cells - bottom of gastric pit
Mucus Neck cells - halfway up the gastric pit.
Mucus Surface Cells - top of rugae
G Cells - “
Digestion. Stomach. Secretions. Mucus Neck and Surface Cells
Secretion: Mucus
Stimulus: Irritation
Function: Forma bolus, lubrication, barrier between chyme and epithelial cells, some weak buffering capacity.
Digestion. Stomach. Secretions. Parietal Cells
Secretion. HCl and Intrinsic Factor
Stimulus. Chewing, smell, sight, distension, gastrin, histamine, acetylcholine, peptides
Function.
HCl denatures protein, kills bacteria and virus, converts pepsinogen to pepsin and inactivates amylase
Intrinsic Factor complexes with B12 to allow absorption.
Digestion. Stomach. Secretions. Chief Cells
Secretion. Pepsinogen and Gastric Lipase
Stimulus. Pepsinogen stimulated by ach, peptides, acidity,
Gastric Lipase stimulated by gastrin
Function.
Pepsinogen converts to pepsin in the presence of HCl and digests polypeptides to smaller polypeptides.
Gastric Lipase digests SCFA and MCFA, though minimal lipid digestion in stomach.
Digestion. Stomach. Secretions. G Cells
Secretion. Gastrin. HORMONE
Stimulus. Ach, peptides, amino acids, distention
Function. Stimulates HCl, pepsinogen, and gastrin secretion. Induces pancreatic and gallbladder secretion. Constricts pyloric sphincter, slowed gastric emptying. Stimulates peristaltic waves.
Absorption. Stomach
Water, fluoride, some lipids, some lipid-soluble drugs (aspirin and alcohol)
Digestion. Small Intestine. Function
Duodenum
Jejunum
Ilum
Digestion. Small Intestine. Hierarchy of Surface Area Adaptations
- Folds in SI
- Villi, finger-like projections. Each villi contains capillaries and lacteals.
- Microvilli - cells of SI wall are called enterocytes and each ends in hair-like projections called microvilli.
- Glycocalyx - glycoprotein-polysaccharides that project from microvilli and attach digestive enzymes.
Digestion. Small Intestine. Goblet Cells
Secrete mucus.
Digestion. Small Intestine. Motility
Segmentation - process by which rhythmic contractions of circular muscles squeeze contents, increasing contact with enzymes. SI contracts more than any other part of GI.
Digestion. Small Intestine. Secretions. Hormones. CCK
Secreting Cells. Duodenum and Jejunum.
Target Organ. Pancreas, liver, gallbladder, stomach, brain
Function. Increases pancreatic enzyme secretions, increases bike formation, increases bike secretion, slows emptying of chyme, increases satiety.
Digestion. Small Intestine. Secretions. Hormones. Secretin
Secreting Cells. Duodenum
Target Organ. Pancreas and stomach
Function. Increases HCO3- secretion and slows emptying of chyme.
Digestion. Small Intestine. Secretions. Hormones. Gastric Inhibitory Peptide (GIP)
Target Organ. Stomach and pancreas
Function. Decreases HCl production (neg feedback) and increases insulin secretion from beta cells.
Neg HCl feedback because it’s the hormone called “inhibitory”
Digestion. Small Intestine. Secretions. Hormones. Glucagon-like Peptide-1 (GLP1)
Target Organ. Pancreas
Function. Increases insulin release from beta cells
Digestion. Small Intestine. Secretions. Enzymes. Enterokinase/Enteropeptidase
Converts trypsinogen to trypsin.
Digestion. Small Intestine. Secretions. Enzymes. Sucrase, Maltase, Lactase
Sucrase - sucrose to glucose and fructose
Maltase - maltose to glucose
Lactase - lactose to glucose and galactose
Digestion. Liver. Function. Hepatic Venous System. Hepatic Portal Vein
Drains fluid from stomach, spleen, pancreas, SI, and colon.
Digestion. Liver. Function. Hepatic Venous System. Hepatic Veins/Arteries
Take blood to and from the liver to the heart.
Digestion. Liver. Function. Hepatic Venous System. Hepatic Portal Duct
Collects bile from liver and connects with the cystic duct coming from
gallbladder to form the commonbile duct.
Digestion. Liver. Function. Hepatic Venous System. Commonbile duct
Connection from cystic duct from gallbladder and the hepatic portal duct. Joins the pancreatic duct where it ends at the Sphincter of Oddi, dumping digestive juices into the SI.
Digestion. Pancreas. Secretions. Exocrine
Gland that secretes product by way of a duct.
Digestion. Pancreas. Secretions. Bicarbonate
Secreting Cells. Duct cells
Function. Neutralizes gastric acid so enzymes can work at optimal pH
Digestion. Pancreas. Secretions. Pancreatic Lipase
Secreting Cells. Acinar cells
Function. Primary lipase, hydrolysis triglycerides to monoglycerides, FA, and glycerol
Digestion. Pancreas. Secretions. Cholesterol Esterase
Secreting Cells. Acinar Cells
Function. Cholesterol esters to cholesterol and FA
Digestion. Pancreas. Secretions. Pancreatic Amylase
Secreting Cells. Acinar Cells
Function. Starch to Dextrin and Maltose
Digestion. Pancreas. Secretions. Trypsinogen
Secreting Cells. Acinar Cells
Function. Peptides to AA
Enteropeptidase (secreted by SI) converts trypsinogen to trypsin, the active form. Trypsin then activates chymotrypsinogen, procarboxypeptidase, pro-elastase, and pro-ribonuclease. Pancreas secretes these enzymes in their inactive form so that they don’t destroy the pancreas of pancreatic duct.
Digestion. Pancreas. Secretions. Chymotrypsinogen
Secreting Cells. Acinar Cells
Function. Proteins to polypeptides.
Digestion. Pancreas. Secretions. Procarboxypeptidase
Secreting Cells. Acinar Cells
Function. Hydrolyzes terminal amino group from the carboxyl group
Digestion. Pancreas. Secretions. Proelastase
Secreting Cells. Acinar Cells
Function. Breaks specific peptide bonds.
Digestion. Pancreas. Secretions. Proribonuclease
Secreting Cells. Acinar Cells
Function. Converts RNA to mononucleotides.
Digestion. Colon. Structure
Ileocoecal Sphincter connects ileum of SI with the first part of the colon.
- Coecum
- Ascending colon
- Transverse colon
- Descending colon
- Sigmoid colon
Sigmoid colon connects with the rectum, anal canal, and anus.
Digestion. Colon. Motility
Small pouches of the colon are called haustra, haustration is segmentation of the haustra.
Digestion. Colon. Absorption
Bacteria ferment soluble fiber to SCFA. Vitamins are also absorbed in colon (vitamin K produced by bacteria in colon).
Bicarbonate Product - Stomach
Parietal Cells
CO2 and H2O yield HCO3- and H+ via Carbonic Anhydrase
HCO3- actively transported out of the basolateral membrane in exchanges for Cl-. This causes the post-enteric alkaline tide and blood becomes alkaline after a meal.
H+ exchanged for K+ (gradient for K+ to enter cell from Na/K pump) at apical membrane, increasing stomach acidity.
Glucose Structure
Aldehyde group, and specific orientation of alcohol group
Galactose Structure
Aldehyde group, and specific orientation of alcohol group
Fructose Structure
Ketone group, alcohol group is on terminal carbon
Oligosaccharides
3-9 sugars long.
Only partially digested by humans; broken down by bacteria in gut causing gas.
Glycogen
Highly Branched
Health Risks of Artificial Sweeteners
May cause: weight gain, learning/memory impairment, dehydration (draws fluid into GI), decreased insulin sensitivity, and dopamine pathways associated with addiction
Starch
Not as branched as glycogen
- Amylose - linear chain, alpha bonds
- Amylopectin - branched, alpha bonds
Dietary Fiber - Risk Associated with Excess
May cause intestinal distress while decreasing ion absorption
Dietary Fiber Function
- May reduce risk of colon cancer by binding harmful substances.
- Promote regularity - keep stool moist and soft.
- May reduce risk of heart disease because blocks cholesterol absorption and SCFA may reduce LDL production.
- Causes feelings of satiety.
- May reduce risk of diabetes by slept digestion and absorption of sugars.
Ketoacidosis
Protein breakdown for gluconeogensis produces ketones. Ketones cause blood to become acidic. Diabetics are at risk for ketoacidosis.
Carbohydrate Function - Metabolic Primer
Carbohydrate are needed for complete oxidation of FAs.
Glycogen Storage
Liver: 70-200g
Muscle: 120-400g
Blood Glucose Elevating Hormones
Glucagon, epinephrine, norepinephrine, cortisol, and GH.
Carbohydrate Absorption
Glucose and Galactose are transported via Sodium Dependent Active Transport. This means energy is required and they raise blood glucose levels more quickly.
Fructose is transported via Facilitated Diffusion. This means no energy is required and fructose does not raise blood glucose as quickly.
Sodium Dependent Glucose Transporter (SGLT) - Sodium Linked Glucose Transporter
Sodium/Potassium Pump pumps sodium out of the cell to create concentration gradient. Sodium flows in via at apical membrane, glucose brought with it against it’s concentration gradient.
Sodium Independent Glucose Transporter (GLUT)
Facilitated diffusion, requires no energy.
Glucose Transporters - GLUT2
Saccharide. Glucose, fructose, galactose.
Location. SI, liver, pancreas (beta cells)
Function. Facilitated diffusion, requires no energy. Allows flow in 2 directions letting liver uptake/release as needed and pancreas to gauge serum levels.
Glucose Transporters - GLUT3
Glucose transporter found in the brain.
Glucose Transporters - GLUT4
Mediated by insulin, found in adipose tissue and muscle
Glucose Transporters - GLUT5
Can transport fructose as well as glucose.
Prebiotics
Nondigestible food ingredients that stimulate bacterial growth
Probiotics
Ingestion of live organisms typically bacteria
Control Of Protein Synthesis
DNA controls protein synthesis; carbohydrate and lipid are synthesized in response to energy needs.
Amino Acids with Sulfur In R Groups
Cysteine and Methionine
Essential Amino Acid
9 Essential Amino Acids
Nonessential Amino Acids
11 nonessential amino acids
Transamination
Process by which amine group from a nonessential amino acid is transferred to a different amino acids and side chain to create an essential amino acid.
Oligopeptide
4-9 amino acids
Hierarchy of Protein Structure
- Primary - sequence of AA
- Secondary - initial folding or pleating of AA chain due hydrogen bonding.
- Tertiary - folding into 3D shape. Due to hydrogen, hydrophobic, and disulfide bonds.
- Quaternary - combination of multiple tertiary polypeptide chains. Ionized R groups bind polypeptides. Can be globular or fibrous.
Denaturation of Proteins
Cause by heat, acidity, alkalinity, mechanical, heavy metals, alcohol, caustic substances.
Does not affect protein’s primary structure.
Digestion. Proteins. Stomach
Secretion. HCl and pepsinogen
Secreting Cells. Parietal and Chief
Function. Denatures proteins. HCl activates pepsinogen to pepsin which beaks polypeptides to smaller polypeptides and AAs.
Gastrin primes body for food bolus by stimulating HCl and pepsinogen secretion
Digestion. Proteins. Small Intestine
Enteropeptidase from SI activates trypsinogen which activates other proteases that break polypeptides into oligo, tri, dipeptides and AA which are absorbed.
Absorption. Proteins. Small Intestine
Oligo, tri, dipeptides and AA are absorbed. SI cells further digest these into AA which enter portal circulation.
Protein Quality
PDCAAS - Protein Digestibility Corrected Amino Acid Score
Animal and Soy - 90%
Legumes - 70-80%
Grains - 60-90%
Protein RDA
Sedentary - 0.8g/kg Endurance - 1.2-1.4 Strength - 1.2-1.7 Veg. Endurance - 1.3-1.5 Veg. Strength - 1.3-1.8
Protein Functions
- Nitrogen Containing Compounds
- Fat Synthesis
- Carbohydrate Synthesis
- Membrane Transport
- Blood Transport - hemoglobin,
albumin carries lipids. - Peptide hormones - insulin and GH
- Motility - muscular contraction
- Buffering - side chains and H+
- Immunity - antibodies
- Growth and Repair
- Enzymatic
- Structure
Independent Variable
Factor being manipulated, outcome is independent. Graphed on x axis
Dependent Variable
Response being measured, outcome is dependent. Graphed on y axis
Research Hypothesis
- Independent Variable
- Dependent Variable
- Type of Interaction (i.e. correlation)
- Direction of Interaction
Null Hypothesis
States that relationship is due to chance.
Reliability
Consistency, ability to reproduce results.
Validity
Accuracy
- Conclusion Validity - measure of if conclusions are correct, compared to gold standard
- Internal Validity - measure of control within experiment
- External Validity - ability to generalize to population from which samples were drawn.
Pearson Correlation Coefficient
-1 = inverse 0 = none 1 = positive
T-Test
Means of 2 groups.
Between - independent samples, unrelated groups
Within - dependent samples, related groups
ANOVA
Comparison between 3 groups.
Between (One-Way) - independent, unrelated groups
Within (Two-Way) - dependent, related groups
Nutritional Assessment - Biochemical - Homeostatic Model Assessment (HOMA-IR)
[Fast Glucose]x[Fast Insulin]/22.5
Glucose Units - mM
Insulin Units - microunits/mL
Problem is that this test is expensive and there is no classification for what a good score is.
Nutritional Assessment - Biochemical - Triglyceride Index (TyG Index)
Ln[Fast TG]x[Fast Glucose]/2
TG Units - mg/dL
Glucose Units - mg/dL
Ln4.65 is the mark of insulin resistance.
Food Pyramid - Grain Recommendation
6oz; 6oz; 9 oz
1800, 2000, 2600 kcal diet
Food Pyramid - Vegetable Recommendation
2.5 cup; 2.5 cup; 3.5 cup
1800, 2000, 2600 kcal diet
Food Pyramid - Fruit Recommendation
1.5 cup; 2 cup; 2 cup
1800, 2000, 2600 kcal diet
Food Pyramid - Oil Recommendation
5 tsp; 5 tsp; 8 tsp
1800, 2000, 2600 kcal diet
Food Pyramid - Dairy Recommendation
3 cup; 3 cup; 3 cup
1800, 2000, 2600 kcal diet
Food Pyramid - Meat and Bean Recommendation
5 oz; 5.5 oz; 6 oz
1800, 2000, 2600 kcal diet
Bicarbonate Product - Pancreas
Pancreatic Duct Cells
CO2 and H2O yield HCO3- and H+ via Carbonic Anhydrase
Opposite as Parietal Cells: HCO3- actively transported out of the apical membrane in exchanges for Cl-. In this way, the pancreas secretes bicarbonate into the pancreatic duct.
H+ exchanged for K+ (gradient for K+ to enter cell from Na/K pump) at basolateral membrane, increasing blood acidity.
