CHAPTER 25 METABOLISM
I.Diet/health and disease
A.Diet associated with diseases
1.vit E,A,C/cancer protection
2.selenium, superoxide dismutase- scavenger of oxygen free radicals
3.alcohol: lowers cholesterol
4.high fat - cancer
5.high sugar - diabetes
6.sugar /tooth decay
7.sugar-additives/hyperactivity
8.calcium/hypertension
9.protein/liver/kidney
10.low fiber/cancer
11.high fat, cholesterol - cardiovascular diseases
B.Risk factors
1.smoking
2.diet - fat, cholesterol, low fiber
3.gender
4. exercise
C.RDA
1.recommended dietary allowances for healthy persons
2.to promote dietary changes
3.not absolute - suggestions
4.to avoid deficiencies or excesses
D.Nutritional status
1.current health conditions as influenced by intake
and utilization of nutrients
2.lab measurements
a.blood- hct
b.urinalysis
II.NUTRIENTS
A. Required in diet to promote growth, maintain health, reproduction with roles in
1.structure
2.regulation of body processes, biochemical reactions
c.metabolism
3.energy
4.maintain homeostasis
B.essential
1.not made by body
2.not made by body in high enough amounts
3.how do we know what is essential?
a.leave it out of animal diets and observe
C.nonessential
1.made in body
D.6 classes
1.CHO
2.protein
3.lipids
4.water- 60% body
5.vitamins
6.minerals
(alcohol provides energy but not essential nutrient)
E. Macronutrients
1.CHO, pro, lipids (g or kg amounts)
F. Micronutrients
1.vitamins, minerals
2.required in mg amounts
G.Energy
1.CHO = 4kcal/g
2.pro = 4kcal/g
3.lipids = 9 kcal/g
4.alcohol = 7 kcal/g
5.kilocalorie ='calorie' (energy)
a.1kcal raises temp of 1 kg water 1 C
b. measure with bomb calorimeter
c.food composition not calculated
III.CARBOHYDRATES
A.simple
1.monosaccharides
2.disaccharides
a.sucrose = fruc+glu
b.maltose = glu+glu
c.lactose = galactose+glucose
B.complex
1.polysaccharides
a.glycogen
(1)glucose units in liver and muscle
b.starch
c.fiber
(1)lack enzymes to digest
(2)increase motility
(3)bind bile salts
(4)interfer with mineral absorption?
C.lactose intolerance
1.lactase insufficient or lacking to digest milk sugar
2.GI disturbances
3.use fermented products as calcium sources or break down lactose
before ingestion (Lact-aid)
D.recommendations
1.55-60% of dietary kilocalories
E.Glucose is major source of energy in body
1.substrate for making ATP
2.stored as glycogen or fat if not needed as ATP
IV.LIPIDS
A.most are triglycerides or neutral fats
B.glycerol backbone and 1,2,or3 fatty acids
C.saturated
1.has all Carbons with maximum H
D.unsaturated
1.double bonds made by removing H
2.omega refers to double bond
3.mono
4.poly
E.essential fatty acids
1.linoleic acid
F.absorbed via lacteals
1.lymph to venous circulation as chylomicrons
G.transported in blood as lipoproteins
1.mix of fats,proteins, cholesterol
2.Very low density lipoproteins
a.made in liver
3.low density lipoproteins
a.deliver to tissues
4.high density lipoproteins
a.return to liver
5.total cholesterol <200mg/dl
6.ratio of HDL/LDL important
a.want more HDL than LDL
b.exercise will increase HDL levels
H.hyperlipidemias
1.high lipids in blood
I.recommendations
1.30% of kcalories
2.10% of kcalories for saturated fat
3.<300mg cholesterol
V.PROTEINS
A.amino acids joined with peptide bonds
B.essential amino acids
1.Phenylalanine
2.Valine
3.Tryptophan
4.Threonine
5.Isoleucine
6.Methionine
7.Histadine - child
8.Arginine - child
9.Leucine
10.Lysine
C.complete protein
1.meet requirements for all amino acids
D.all amino acids must be present to make protein
E.complementary proteins
1.cereal/milk
2.peanut butter/bread
3.rice/beans
F.if energy is low protein spent as energy
G.recommendations
1.0.8 g/kg
a.2.2lbs/kg
H.amino acids deaminated (remove N)
1.increases work of liver and kidney
2.protein restriction with damage to above organs
3.high protein diets for weight loss harmful
4.forces body to use fats - ketosis
I.Nitrogen balance
1.rate of protein synthesis equals break-down
2.positive balance
a.excretion of nitrogen is less than ingested
b.occurs with growth,repair,pregnance
3.negative balance
a.excretion of nitrogen is more than ingested
breaks down protein to use as energy
b. injury, illness
VI.MALNUTRITION
A.kwashiorkor
1.protein deficiency
2.age 1-3, edema-pot belly, thin extremities
B.marasmus
1.all nutrients deficient
2.wasting away
VII.VITAMINS
A.Fat soluble
1. A,D,E,K
2.stored
3.toxicity from excesses
4.growth and maintenance roles
B.Water soluble
1.B's,C
2.required frequently
3.less likely toxic due to excretion in urine
4.most important as coenzymes
C.Vitamin A
1.retinol,retinal,retinoic acid
2.roles
a.vision
(1)piggment molecules in retina -rods/cones
b.mucous membrane integrity
c.immunity
d.growth
3.recommendations
a.1000ug RE men
b.800ug RE women
4.deficiency
a.night blindess
b.decreased membrane integrity
5.toxicity
a.birth defects
6.sources
a.deep green,gold,red, orange foods
b.fruits, vegetables,dairy
D.Vitamin D
1.UV radiation of precursor molecule in skin
2.converted to active form in liver,kidney
3.acts like hormone in bone formation
a.promotes bone mineralization
b.absorption of calcium from GI
4.deficiency
a.rickets -bowed legs
b.osteomalacia
(1)bone softens
5.toxicity
a.kidney stones
6.recommendations
a.10ug/day
7.sources
a.fortified milk,margarines
E. Vitamin E
1.antioxidant role
2.immune system
3.deficiency
a.neuralmuscular disfunction
b.legs cramping
c.breaking of RBCs
4.sources
a.plant oils
b.green leafy vegetables
c.liver,egg yolks
F. Vitamin K
1.functions in blood clotting
2.made by E. coli in large intestine
3.recommendations
a.65 ug/day women
b.80 ug/day men
4.deficiency
a.hemorrhagic disease
b.newborns
(1)sterile gut
(2)injection
5.source
a.cabbage-type veggies
b.liver
c.milk
G.The B vitamins
1.thiamin
a.functions
(1)part of thiamin pyrophosphate
(2)coenzyme
(3)supports appetite and nerve function
b.recommendations
(1)0.5 mg/1000 kcal/day
c.deficiency
(1)beriberi
(2)heart problems
(3)muscle and nerve problems
d.sources
(1)pork,liver
(2)whole grain and enriched breads
(3)legumes,nuts
2.riboflavin
a.functions
(1)energy release
(2)part of coenzymes:FAD and FMN
b.recommendations
(1)0.6 mg/1000kcal
c.deficiency
(1)ariboflavinosis
(2)mouth,gums,tongue
(3)skin rash
(4)nervous system and eyes
d.sources
(1)milk,yougurt,cottage cheese
(2)meat
(3)leafy green veggies
(4)whole grains and enriched breads
e.light sensitive
3.niacin
a.functions
b.coezymes:NAD and NADH
c.recommendation
(1)6.6 NE/1000kcal
d.deficiency
(1)pellagra
(2)digestive and nervous problems
(3)skin problems
e.sources
(1)milk eggs
(2)meat,puoltry,fish
(3)whole grain and enriched
(4)nuts and all protein foods
4.biotin
a.coenzyme
(1)energy metabolism
(2)fat metabolism
(3)amino acid etabolism
(4)glycogen syntheses
b.recommendations
(1)no RDA 30-100ug
c.deficiency
(1)loss of appetite
(2)muscle pain
(3)dry scaly skin
d.egg hite protien avidin binds biotin
e.synthesized in GI
5.pantothenic acid
a.funciton
(1)part of Co A
(2)energy metabolism
b.recommendations
(1)no RDA
(a)4-7mg
c.deficiency
(1)intestinal distress
(2)fatigue
(3)insomnia
d.heat labile
6.B6
a.Functions
(1)part of Pyridoxal phosphate
(2)converts tryptophan to niacin
(3)RBC formation
b.recommendations
(1)RDA 0.016 mg/g protein/day
c.deficiency
(1)weakness, irritability,insomnia
(2)impaired motor function
d.toxicity
(1)numbness of mouth
(2)nerve damage
e.sources
(1)green leafy vegetables
(2)meats,fish,poultry,shellfish,legumes
(3)fruits
(4)whole-grains
7.Folate
a.function
(1)part of THF tetrahydrofolate and
DHF dihydrofolate
(2)coenzyme in DNA synthesis
b.recommendations
(1)3ug/kg body weight
c.deficiency
(1)impairs cell division
(2)impairs protein synthesis
(3)anemia
d.sources
(1)leafy green veggies
(2)fruits
(3)legumes and seeds
(4)liver
8.Vitamin B12
a.function
(1)coenzyme in cell shythesis
(a)maintains nerve cells
b.recommendations
(1)2mg/day
c.deficiency
(1)lack of intrinsic factor
(2)paralysis
(3)large cell type anemia
(a)pernicious anemia
d.sources
(1)meat, fish,poultry,shellfish
(2)milk,cheese,eggs
H.Vitamin C
1.functions
a.antioxidant
b.collagen formation
c.stress hormones
2.recommendations
a.RDA 60 mg/day
3.deficiency
a.scurvy
b.capillary hemorrhages
4.toxicity
a.GI distress
b.kidney stones
c.dependency
5.sources
a.fruits and veggies(bell pepper)
b.citrus
c.potatoes
VIII.MINERALS
A.sodium
1.roles
a.regulates extracellular fluid
b.acid-base balance
2.recommendations
a.min 500mg
b.max 2000-3000mg
c.1 tsp table salt =2000mg
3.deficiency
a.vomiting,diarrhea,sweating depletes
b.dehydration
4.toxicity
a.edema
b.hypertension
B.chlorine (as chloride ion)
1.roles
a.anion in extracellular fluid
b.part of HCl
2.recommendations
a.750mg/day
3.source in all foods
C.potassium
1.roles
a.muscle contraction
b.major intracellular cation
c.fluid/electrolyte balance
d.nerve transmission
2.recommendations
a.2000mg/day
3.source