Nutrition - Macronutrients

Front 1

define RMR

Back 1

E required to maintain body systems, at rest and post-absorptive; ~60% of total E requirementn

Front 2

what factors influence RMR and total energy consumption?

Back 2

Influenced by sex, age, weight, physical activity (lifestyle);

RMR is proportional to lean muscle mass

Front 3

how many calories/g are in:
1) proteins
2) CHO
3) fat
4) alcohol

Back 3

1) 4
2) 4
3) 9
4) 7

Front 4

define:
1) glycemic index
2) complex vs. simple sugars

Back 4

1) defines rate of increase of blood glucose after ingestion of food

2) complex = polysaccharides; simple = mono/disaccharides

Front 5

what defines caloric requirement for CHO intake?

Back 5

goal: avoid ketosis & breakdown of body proteins for gluconeogenesis

Front 6

define & categorize dietary fiber

Back 6

nondigestible carbohydrates from plant cell wall

insoluble fiber - ↑ fecal bulk, accelerates colonic transit

soluble fiber - processed by gut bacteria --> release short chain FAs (can also lead to H2 & CH4 gas = bloating)

Front 7

what are the probable health benefits of dietary fiber?

Back 7

1) ↓ absorption of fats & cholesterol (↑ loss in feces)

2) ↓ rate of glu absorption (moderate glycemic index)

3) ↓ colonic transit time - avoid constipation, hemarrhoids, diverticulitis

Front 8

what is the PDCAAS method of ranking dietary proteins?

Back 8

Protein Digestibility Corrected AA Score

dietary proteins ranked relative to egg protein (gold std, 1.0)- AA composition, ease of digestibility & absorption

Front 9

contrast animal vs. vegetable proteins

Back 9

animal proteins score higher on PDCAAS than vegetables; more digestible & absorbale, greater variety of AA (need to combine multiple vegetable sources to get well balanced AA diet)

Front 10

define protein complementation

Back 10

diff foods may be deficient in diff AA and abundant in others-- eating a variety of foods eliminates risk for a specific AA deficiency

Front 11

define nitrogen balance

Back 11

ratio of amts of N2
consumed (diet)
vs.
lost (urea, ammonia, sloughed off cell materials)

Front 12

causes of
positive, neutral, negative
nitrogen balance

Back 12

positive: periods of growth, expansion of muscle tissures from excercise

negative: fasting, starvation, protein malnutrition, burn/trauma recovery

Front 13

what is the "protein sparing" concept of dietary carbohydrates?

Back 13

if present in adequate amts, CHO minimizes the need to perform gluconeogenesis (and the need to breakdown tissue proteins for gluconeogenic precursors)

Front 14

describe nomenclatures for FA structures (2 types)

Back 14

1) -COOH = C1
e.g.: arachidonic acid, 20:4 (5, 8, 11, 14)
20 C's
4 double bonds (between C5-6, 8-9...etc)

2) terminal -CH3 = ω-C
-C-COOH (C2) = α-C, C3= β, C4 = γ-C
e.g. linoleic acid [18:2 (9, 12)] = ω-6-FA b/c closest double bond to ω-C end begins 6C from the end (counting from ω-C as the new C1)

Front 15

what foods are rich in
1) saturated fats
2) monounsaturated fats
3) polyunsaturated fats

Back 15

1) butter, lard, animal (most have higher % of saturated, except fish), cocunut oil, palm oil

plants = unsaturated, liquid @ RT
2) olive, canola, sunflower oil
3) soybean, corn oil

Front 16

what is fiber?

Back 16

extended sugar polymers from plants, indigestible

Front 17

what are possible adverse effects of fiber?

Back 17

phytates (abundant in fiber) bind to Zn, essential FAs & prevent absorption

fermentation of soluble fiber --> bloating & flatus

Front 18

what is kwashiorkor?
what causes it?

Back 18

chronic dietary protein insufficiency, adequate caloric intake

often seen in children after being weaned from breast milk and placed onto a carb rich diet

Front 19

what are pathophys & sx of kwashiorkor?

Back 19

↓ protein synthesis in many tissues
↓ tissue fxn & stability

swollen belly (can't maintain H2O compartments)
thinning hair
dermatitis
retarded growth/dvlpmt
weak immune responses

Front 20

what is marasmus?

Back 20

deficient in both protein AND calories

Front 21

what are sx of marasmus?

Back 21

w/ severe caloric deficiency, muscle AND fat mass lost thru catabolism

less interruption of visceral organ fxn than kwashiorkor

Front 22

how does consuming cholesterol & fats (sat, monounsat, polyunsat) influence blood cholesterol & risk for CVD?

Back 22

1) Dietary (only in animal sources) has little effect on plasma cholesterol. ↑ plasma chol = ↑ atherosclerosis & LDL; ↑LDL = ↑CVD

2) sat FAs = most impt factor in blood chol levels (total & LDL), esp 12, 14, 16C FAs. Dairy & meat products, coconut & palm oils.

3) normal amts of unsat (mono & poly) = ↓LDL/total cholesterol; small ↑ in TGs.

high amts of polyunsat = ↓ HDL, ↑ LDL-oxid'n (& ↑ foam cell formation)

monounsat FAs = ↓ LDL, little/no ΔHDL

Front 23

what % of total caloric intake should come from
1) sat fat
2) monounsat fat
3) polyunsat fat

Back 23

all fats: 30% of total caloric intake
10% from each type of FA

Front 24

contrast n6 vs n3 polyunsat FAs
1) biological fxn
2) risk for CVD?

Back 24

n(ω)-6 (eg, linoleic acid) (corn, safflower, sunflower)=
A) ↓ plasma cholesterol (both LDL & HDL) *when substitued for saturated fats*
B) generates arachadonic acid
= ↑ inflammation & plt aggr'n

n(ω)-3 FAs (fish, soybean, canola)= inhibit conversion of AA to TXA2 by plts (convert to TXA3 instead = less thrombogenic)

SMASH fish (salmon, mackerel, anchovies, sardines, herring)

Front 25

contrast cis- vs. trans- FAs
1) biological fxn
2) influence on blood cholesterol
3) risk for CVD

Back 25

trans
1) not in plants, only a little in animals; mostly during hydrogenation of veg oils (eg margarine)
2) ↑ plasma cholesterol, ↑ risk CVD

cis
1) naturally occuring
2) don't ↑ plasma cholesterol,

Front 26

Olestra
1) what is it
2) possible benefits
3) possible liabilities

Back 26

1) not hydrolyzed by pancreatic enzymes, so non-absorbable, energy-free fat substitute

3) interference w/ absorption of fat soluble nutrients;

Front 27

how are fats from animals vs. plants different?

Back 27

1) animals: more saturated
2) plants: mostly unsaturated

Front 28

what are the essential fatty acids?
what are EFAs biological roles?
what are sx of EFA deficiency (rare)?

Back 28

linoleic & linolenic

required for fluidity of membrane structure
eicosanoid synthesis

scaly dermatitis, hair loss, poor wound healing

Front 29

when does adipose growth by hyperplasia vs. hypertrophy occur?

Back 29

hyperplasia: times of major growth & excessive caloric intake

hypertrophy: excessive caloric intake

Front 30

characteristics of adipocytes WRT location:
subQ vs. visceral/intra-abd

Back 30

1) subQ: smaller, pick up/release free FA into gen circulation

2) visceral: larger, more sensistive to adrenergic stimulation, higher metabolic activity, release FAs into portal v.