Nutrition and Supporting Sciences Flashcards
Cellular oxidation
Enzymes: proteins, organic catalysts that control reaction
Coenzymes: enzyme activators, include some vitamins (pantothenic acid, thiamin, riboflavin, niacin are needed for energy production)
Substrate: substance upon which enzymes work
Cofactor: assists enzymes minerals
Calorimetry
Carb alone: 1
Protein alone: 0.82
Fat alone: 0.7
Mixed intake: 0.85
Carb: order of sweetness
fructose, invert sugar, sucrose, glucose, sorbitol, manniol, galactose, maltose, lactose
Protein: amino acids
sulferous: cysteine, cystine, methionine
Essential: threonine, valine, tryptophan, isoleucine, leucine, lysine, phenylalanine, methionine, histidine (TV, TILL PMH)
Soybeans low in methionine
Fat: unsaturated
Most polyunsaturated: safflower
Omega-6 (linoleic):
if it replaces CHO: lower LDL, higher HDL
if it replaces sat fat: lower total chol, lower HDL
Omega-3 (linolenic):
EPA & DHA
the location of the first double bond, counted from the MEHTYL end of the fatty acid is designated by the omega sign
Fat: hydrogrenation
process of adding hydrogen to unsat fatty acids to increase saturation and stability
trans fatty acids: hydrogens are across from each other, pack as tightly as SFA in membranes, intake can influence membrane fluidity and could be harmful to cell function, found in milk fat, margarines, shortenings, frying fats
Types of fat
Sat: coconut oil, palm kernel oil, cocoa butter, butter, palm oil, canola (medium-chain are SFAs between 6 and 12 carbons naturally found in milk fat, coconut oil, and palm kernel oil)
Mono-unsat: olive, canola, peanut, sunflower, coconut (MCT source)
Poly-unsat: safflower, corn, soybean, cottonseed, sunflower, palm kernel
Fat: function
energy, insulation, padding, depresses gastric secretion so delays emptying
Has less oxygen more carbon than carbohydrate so provides more energy (more carbon atoms for oxidation)
Winterized oil
salad dressings, won’t crystalize when cold
corn, soy and cottonseed oils are winterized, NOT olive ol
Vitamin A (fat sol)
PROPERTIES: toxic level 10k IU
FUNCTION: skin, vision
SOURCES: yellow, orange fruits, dark leafy green veg, cantaloupe, fish, liver, carrots, fortified skim milk, apricots, sweet potato
DEFICIENCIES: nyctalopia (reversible night blindness), xeropthalmia (permanent corneal damage), hyperkaratosis
Vitamin D (fat sol)
PROPERTIES: cholesterol is precursor
FUNCTION: D3 cholecalciferol to D2, ca & protein metabolism
SOURCES: sunlight, egg yolk, fortified milk
DEFICIENCIES: rickets, osteomalacia (adult rickets)
Vitamin E (fat sol)
PROPERTIES: one of the least toxic vitamins
FUNCTION: antioxidant
SOURCES: veg oils (cottonseed), whole grains, green vegetables, almonds
DEFICIENCIES: hemolytic anemia
Vitamin K (fat sol)
PROPERTIES: synthesized by bacteria in lower intestinal tract
FUNCTION: forms prothrombin in liver, aids blood clotting
SOURCES: spinach, kale, broccoli, green, leafy vegetables
DEFICIENCIES: hemorrhage, affected by mineral oil, antibiotics and anticoagulants
Vitamin B1 (Thiamin)
PROPERTIES: lost as temp or pH rises, heat stable in acid
FUNCTION: oxidation of CHO (incr CHO incr needs), metabolism of pyruvate)
SOURCES: grains, wheat germ, pork, liver
DEFICIENCIES: beriberi, muscle weakness, foot drop, memory loss, tachycardia (low erythrocyte transketolase, high plasma pyruvate)
Vitamin B2 (Riboflavin)
PROPERTIES: lost in UV light
FUNCTION: energy release from protein, RBC production
SOURCES: lier, kidney, meat, milk
DEFICIENCIES: cheilosis (cracked lips), stomatitis (mouth corner cracks), magenta tongue
Vitamin B3 (Niacin)
PROPERTIES: tryptophan is precursor, essential in all cell metabolism
FUNCTION: metabolism of CHO, protein, fat
SOURCES: protein, peanuts, RTE cereals, chicken, rice, yeast, milk
DEFICIENCIES: pellagra, dermatitis, diarrhea, dementia, beefy bright red tongue, symmetrical pigmented rash in sun
Vitamin B9 (Folate)
PROPERTIES: PABA precursor
FUNCTION: DNA synthesis, forms RBC, prevents neural tube defects
SOURCES: fortified dry cereal, liver, kidney, green leafy veg, citrus fruits, lentils, beans
DEFICIENCIES: megaloblastic microcytic anemia, fatigue, irritability, dyspnea
Vitamin B6 (Pyridoxine)
PROPERTIES:
FUNCTION: coenzyme in amino acid metabolism (incr protein need incr B6)
SOURCES: meat, wheat, corn, yeast, pork, liver, RTE cereals
DEFICIENCIES: seizures, anemia, dermatitis, glossitis, peripheral neuropathy
Vitamin B12 (Cyanocobalamin)
PROPERTIES: contains cobalt, bound by IF in gastric juice
FUNCTION: coenzyme in protein synthesis, forms RBC
SOURCES: liver, meat, milk, kidney, eggs, fish, cheese
DEFICIENCIES: macrocytic megaloblastic anemia, pernicious anemia, due to lack of IF after surgery
B5 (Pantothenic acid)
PROPERTIES:
FUNCTION: Coenzyme A- energy synthesis of fatty acids
SOURCES: animal foods, grains, legumes
DEFICIENCIES: rare, parasthesia in feet
Vitamin C (ascorbic acid)
PROPERTIES: most easily destroyed, structure like glucose, needs acid pH, destroyed by heat, alkaline, oxidation
FUNCTION: changes proline into hydroxyproline into collagen, wound healing, aids iron absorption
SOURCES: citrus fruits, potatoes, papaya, dark green & yellow veg
DEFICIENCIES: scurvy, poor wound healing, bleeding gums, petechiae
Vitamin B7 (Biotin)
PROPERTIES: synthesized by intestinal bacteria
FUNCTION: coenzyme in fatty acid synthesis, conerts pyruvate to oxaloacetate in GNG
SOURCES: liver, kidney, egg yolk, yeast
DEFICIENCIES: muscle pain, dermatitis, glossitis
Myo-inositol
PROPERTIES: in plants as phytic acid
FUNCTION: binds calcium, zinc, iron membrane structure
SOURCES: outer husks of cereal, leafy green veg
DEFICIENCIES:
Calcium
PROPERTIES: most abundant mineral, regulated by PTH, absorption aided by vit D, acid, lactose, calcitonin lowers serum ca by inhibiting bone resorption
FUNCTION: blood clotting, cardiac function, nerve transmission, smooth muscle contractility
SOURCES: dairy products, leafy vegetables, legumes
DEFICIENCIES: hypocalcemia leads to tetany
Phosphorus
PROPERTIES: second most abundant mineral, part of DNA, RNA, ATP
FUNCTION: phospholipids transpot fat through lymph and blood; bone and teeth
SOURCES: meat, milk, poultry eggs, fish, cheese
DEFICIENCIES: rare
Iron
PROPERTIES: trace mineral, part of Hgb, food in ferric form, absorbable as ferrous, stored as ferritin
FUNCTION: oxygen transport
SOURCES: heme iron= animal foods, meat, fish, poultry; non-heme= cereals, veg, poorly absorbed; gastric juice and vit C aid absorption; calcium absorbed if oxalates are present (eggs, tea, milk, cheese do not help)
DEFICIENCIES: pale tongue, fatigue, anemia, spoon-shaped nails, pale conjunctivae (mucous membranes lining eyelid)
Magnesium
PROPERTIES: part of chlorophyll, 50% in bone, 50% in cells
FUNCTION: protein and fatty acid synthesis, stabilizes structure of ATP, high protein, calcium, vit D incr needs
SOURCES: most foods, milk, bread
DEFICIENCIES: rare, tremors
Zinc
PROPERTIES: trace mineral, excess leads to copper or iron deficiency
FUNCTION: incr taste acuity, enhances insulin action, stabilizes DNA, RNA, cell division
SOURCES: meat, liver, eggs, fish, phytates and copper decr absorption
DEFICIENCIES: reduced immune function, alopecia, poor wound healing, hypogeusia
Iodine
PROPERTIES: trace mineral
FUNCTION:
SOURCES: seafood, iodized salts
DEFICIENCIES: goiter
Fluoride
PROPERTIES: trace mineral
FUNCTION: teeth, bones
SOURCES: soil, water
DEFICIENCIES: dental caries
Copper
PROPERTIES: trace mineral, attached to protein, ceruloplasmin
FUNCTION: Hgb synthesis, aids iron absorption
SOURCES: liver, kidney, shellfish
DEFICIENCIES: Wilson’s disease, rare: microcytic anemia, neutropenia
Selenium
PROPERTIES: cooperates with vitamin E
FUNCTION: antioxidant, tissue respiration
SOURCES: soil, grains, meat, fish, poultry, dairy
DEFICIENCIES: myalgia, cardiac myopathy
Manganese
PROPERTIES: trace mineral
FUNCTION: central nervous system
SOURCES: whole grains, legumes, nuts
DEFICIENCIES: unlikely
Chromium
PROPERTIES: absorption enhanced by vit C, niacin, ultra-trace mineral
FUNCTION: aids insulin action, glucose metabolism
SOURCES: yeasts, oysters, potatoes, liver
DEFICIENCIES: insulin resistance
Cobalt
PROPERTIES: exists with B12, stored in liver
FUNCTION: maturation of RBCs
SOURCES:
DEFICIENCIES: related to B12 deficiency
Sulfur
PROPERTIES: part of amino acids, cysteine, methionine
FUNCTION: component of organic molecules
SOURCES: meat, fish, eggs, poultry
DEFICIENCIES:
Choline
PROPERTIES: component of lecithin
FUNCTION: transports lipids as acetylcholine
SOURCES: fat in eggs, milk, liver, soybeans
DEFICIENCIES: dental caries
Nutrients that aid glucose metabolism
chromium & zinc
As energy expenditure of the body increases, need more of these:
thiamin, niacin, riboflavin, pantothenic acid
Electrolyte concentration
mEq= mg / atomic wt x valence
Insensible water loss
0.8-1.2 liters / day
Electrolytes
extracellular: Na (22.99), Ca (40.08), Cl (35.45), HCO3 (61.02)
inracellular: K (39.09), Mg (24.31), P (30.97)
Dehydration
nausea, dizziness, sunken eyes, fever, hyperventilation, excessive sweating, concentrated urine, dry inelastic skin, incr in solutes (BUN), tachycardia, headache, fatigue, decr appetite, rapid wt loss
serum sodium is the BEST assessment parameter for fluid status. Hypernatremia > 145 mEq/L (> 145 mmol/L) is assoc with dehydration. Hyponatremia is assoc with over-hydration.
Acid base balance in the body
a change in one side of the buffer brings about a compensatory change in the other sid to maintain balance
RESPIRATORY: carbonic acid (incr H2 CO3 is acidosis; decr H2 CO3 is alkalosis)
METABOLIC: bicarbonate base (decr HCO3, incr H+ is acidosis or ketosis; incr HCO3, decr H+ is alkalosis)
Acid base levels
pH 7.4
HCO3 (base, kidney): 24-28
pCO2 (acid, lungs): 35-45
Pregnancy wt gain guidelines
BMI 18.5-24.9: 25-35 lb
BMI <18.5: 28-40 lb
BMI 25-29.9: 15-25 lb
BMI >=30: 11-20 lb
At risk pregnancy
- failure to gain 4 lb in last half of pregnancy
- <16 or >=35 years old
- pregnant adolescent is high risk and needs iron, calcium and zinc
Normal birth wt
2500-4000 g
LBW is <5.5lb (<2500 g)
Infant calorie needs
needs the most calories., protein, water / unit wt
0-6 months: cal= EER 520F 570M prot= RDA 9.1g H2O= 125-155ml/KG, 1.5ml/kcal fat= minimum of 30g per day
7-12 months: cal= EER 676F 743M prot= RDA 11g H2O= 125-155ml/KG, 1.5ml/kcal fat= minimum of 30g per day
recommend exclusive breastfeeding for the first 4-6 months, then supplemented by weaning foods for at least up to 12 months (add solids when sitting posture can be sustained and extrusion reflex diminishes)
breast-fed infants need to supplement with 400IU vit D and .25mg fluoride/day after 6 months
Infant formula
20 cal/ounce; need 2 1/2 oz/lb/day
has more protein and more iron than human milk but lacks antibodies
vit D
recommended iron-fortified formula
WHO growth charts
1) wt for length/stature (birth-24 months, young children 2-5): detects short term changes in nutritional status
2) stature/length for age (0-24 month, 2-20 yrs): reflects long term nutritional status
3) weight for age (0-24 months, 2-20): not use to classify under/over weight, short term marker of growth
4) BMI for age percentiles (starting age 2): age and sex specific
FTT
failure to thrive may result from acute or chronic illness, restricted diet, poor appetite, lack of fiber leading to chronic constipation, diminished intake
Adult protein requirements
RDA
Males >=19 years: 56 g
Females >=19 years: 46 g
Exercise needs
hydration: 16 oz. water for every 1 lb body weight lost
BEFORE activity: limited research suggests 10ml/kg of a high sodium containing beverage prior to activity that is 1-4 hours long
DURING activity: to maintain hydration, beverages provided in a volume that equals 100% fluid lost during moderate-vigorous activity plus 5.5-15% CHO and 55-164mEq Na
Exercise physiology
at rest and during normal activities, fats are the primary energy source (80-90%); carb 5-18%, protein 2-5%
during low to moderate intensity aerobic activity (long duration, steady pace and endurance training) fat is a significant energy source
Herbal interactions w/ clotting/bleeding
Black cohosh- may cause clotting Garlic- reduces clotting time Ginger- affects bleeding Ginkgo biloba- avoid use with warfarin Ginseng- avoid with warfarin
Valerian root- avoid with liver disease
Bile
produced in the liver, stored in the gallbladder, liver stores glycogen and synthesizes glucose
Digestion in stomach (chemical)
start of proteolysis by protease pepsin and HCL; limited continuation of start hydrolysis by salivary amylase
Mechanical digestion
acidic chyme enters duodenum, mixes with fluids and bicarbonate ions (from pancreas) which neutralize acid
Bacterial digestion
large intestine absorbs water, salts, and the vitamins synthesized by bacterial (vit K, B12, thiamin, riboflavin) which are used by GI mucosal cells
bacteria converts malabsorbed CHO and fibers into SCFA (butyrate, propionate, lactate) which stimulate water and sodium absorption in the colon, and provides substrates for energy production; and gases (H2, CO2, N CH4)
Enzymes for CHO digestion
1) maltase, sucrase (at 30th wk)
2) lactase (at birth)
3) pancreatic amylase (6 months after birth)
Sources of glucose
dietary, liver glycogen, products of intermediate metabolism (reconversion of lactic acid and pyruvic acid)
1) 100% carbohydate
2) 58% protein - glucogenic amino acids (yield glucose deamination)- alanine the MOST glucogenic
3) 10% fat- glycerol can be converted to glucose
Hormones control BG level
1) insulin- (lowers BG) BETA cells of pancreas
2) glucagon- (raises BG) ALPHA cells of pancreas
3) glucocorticoids- (raises BG) protein, requires pyridoxine
4) epinephrine- (raises BG) adrenal medulla, stim symp nervous system, liver and muscle glycogenolysis, during catabolic stress
5) growth hormone, ACTH- (raises BG) insulin antagonist
Glycolysis + TCA cycle
REVIEW image w/ post-it note
Protein metabolism
pyridoxine is needed for the transport of amino acids
BCAAs: valine, leucine, isoleucine
Exercise releases alanine from muscle protein, it is transported to the liver, deaminated, and converted to glucose. Also during exercise, the oxidation of leucine increases
Quality of protein
BV- biologic value uses nitrogen balance techniques to determine fraction of absorbed nitrogen retained for growth and maintenance (eggs have BV of 100)
NPU- net protein utilization measures the amount of protein actually used
(N intake - N output) / N intake
Protein digestibility corrected amino acid score (PDCAAS)
represents amino acid score after correcting for digestibility
Protein hormonal control
1) pituitary growth hormone, thyroid hormone, insulin, testosterone- anabolism
2) adrenal steroids (glucocorticoids) protein catabolism- stimulate gluconeogensis
Nutrient transport
Active transport: most nutrients (glucose, amino acids, Na, K, Mg, Ca, Fe), sodium pump
Factors that aid vitamin and mineral absorption
- A: bile salts, pancreatic lipase, fat
- D: hydroxylated in the liver, then in kidney, needs bile salts, acidity of chime accompanies Ca, P absorption
- riboflavin: phosphorus
- B12: ileum, stomach secretions (HCL, intrinsic factor)
- iron: HCL, calcium (binds oxalates)
- folate: zinc-dependent, cleaves polyglutamate to monoglutamate, folic acid in fortified foods and supplements is present as monoglutamate
