Nutrition II
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Transcript of Nutrition II
Nutrition II
Nutrients
Carbohydrate
Fat
Protein
Macronutrients
Vitamins
Minerals
H2O
Micronutrients
Micronutrients and H2O vitamins and minerals
found in variety of foods
balanced diet no supplementation (Ca++)
Vitamins Accessory nutrients (C,H,O)
Supplied thru diet (except D)
Manufactured during photosynthesis
Types of Vitamins Lipid soluble
- A, D, E, and K
Water soluble- C- B: B1, B2, B6, B12, niacin, folic acid
Lipid Soluble
Should not be consumed in excess
E.g. kidney damage 20 excess D
Water Soluble Generally not stored
Excess is voided
Role of Vitamins Links & regulators in energy
releasing reactions
Control tissue synthesis
SupplementationProper Diet Repeated Use
Supplementation
However?
Supplementation Exceptions:
- C- B – folic acid- B1 and B6 (some athletes)- B12 in vegetarians
Antioxidant Role Free radicals - highly chemically
reactive molecules/fragments Produced in body:
- O2-, H202, OH-
Produced in environment:- smoke, pollutants, medications
Antioxidant Role free radicals oxidative
stress/cellular damage
oxidation of LDL atherosclerosis
Oxidataive stress cell deterioration, advanced aging, CA, DM, CAD
Antioxidant Vitamins A (& precursor -carotene), C , E
Protect plasma membrane
-carotene & C CA
E & -carotene CAD, blood clots
Recent Research roundworm life by 50%
synthetic drugs that mimic: superoxide dismutase catalase
persist longer than vitamins
Vitamins and Exercise B-complex – coenzymes for CHO,
lipid, & protein catabolism energy
Contribute to Hb synthesis (RBC)
Megavitamins 10-1000x RDA
Excess vitamin ResultC serum uric acid goutB6 Liver disease/nerve damageB2 Impaired visionE Headache, fatigue,blurred vision, GI
disturbance, muscular weakness, low BG
A Nervous system toxicityD Kidney damage
Minerals Elements Constituents of enzymes, hormones,
vitamins Combine w/ other chemicals (calcium
phosphate in bone, heme blood) Critical for certain processes (muscle
contraction)
Minerals Naturally occurring Supplementation unnecessary
(except Ca, Fe) Excess can be toxic
Roles of MineralsStructure (bones/teeth)Function:
- heart rhythm- muscle contraction- neural conductivity- acid-base balance
Roles of MineralsRegulation Cell metabolism
(enzymes/hormones)
Balance catabolism/metabolism electrolytes
Calcium Osteoporosis :
- less bone density to start- reduced intake teenage years- activity- estrogen / menopause
Other factors: smoking, alcohol abuse
Prevention Ca++ supplementation Vitamin D availability Estrogen therapy W/b activities (consistent) Avoid excessive meat, salt, coffee,
alcohol
Prevention
20 amenorrhea estrogen
Phosporus
Provides rigidity to bones & teeth Essential to ATP, CP Combines w/ lipids plasma
membrane Buffer acids produced 20 heavy
exercise
MagnesiumInvolved in: anabolism of serum glucose
liver/muscle glycogen catabolism of glucose, fatty acids,
AA anabolism of lipids & proteins nerve conduction and muscle
action
Iron Found in:
- hemoglobin- myoglobin- cytochromes
Iron-deficiency anemia hemoglobin conc. Sluggishness Loss of appetite Reduced capacity for exercise Common in
Iron-deficiency anemia in Females Pregnancy
Menstruation
Vegetarian diet- animal Fe more readily absorbed
Iron RDAAge Iron (mg)
Children 1 – 10 10Males 11 – 18 12
19 10Females 11 – 50 15
51 10Pregnant 30Lactating 15
Exercise-Induced Anemia? Loss of iron thru:
- Perspiration- Urine 20 RBC destruction & temp.- Spleen activity- Mechanical RBC destruction
Probably minimal
Supplementation? Hematological work-up Accumulate to toxic level and
contribute to: Liver disease DM Heart damage / CAD Joint damage
Electrolytes Na+ - blood plasma/extracellular
Cl- - blood plasma/extracellular
K++ - chief intracellular
Na+ and Cl- Modulate fluid exchange
Regulate exchange of nutrients and wastes between cell and external medium
Na+ and K++ Establish electrical gradient across
cell membranes for: Nerve impulses Muscle contraction Gland function
Na+ induced HTN 1/3 of individuals w/ HTN
Typical diet exceeds RDA by 10x
Not always the problem
Minerals & Exercise Excessive loss Impair heat tolerance &
performance Cramps Exhaustion Heat stroke
Minerals & Exercise
Good diet
Glass of OJ replaces Ca, K, Mg lost in 3 L of perspiration
Supplementation
Water 40 – 60% of body mass
65 – 75% of muscle
50% of body fat
Water 62% extracellular
38% intracellular
Functions of Water Transport and reactive medium
- diffusion of gases- transportation of nutrients,
gases, & wastes Heat-stabilizing Lubricates joints Structure & form
Water RegulationInput (ml) Outpu
t(ml)
Food 1000
Urine 1250
Fluids 1200
Feces 100
Metabolism
350 Skin 850
Lungs 350Total 255
0Total 2550
Water Regulation in Hot Weather during ExerciseInput (ml) Outpu
t(ml)
Food 1000 Urine 500Fluids 1200 Feces 100Metabolism
350 Skin 5000
Lungs 700Total 2550 Total 6300
Water and Exercise 100% relative humidity
- evaporation impossible- loss of cooling mechanism
No humidity- optimum cooling- excessive fluid loss plasma volume circulatory strain
Assessing Fluid Loss Accurate body weight pre- and
post-exercise
1 lb. BW = 450 mL (15 oz.) dehydration
Hyponatremia Water intoxication 20:
Loss of electrolytes (Na+)
Large ingestion of water
Hyponatremia Dilution of extracellular Na+
Headache, confusion, malaise, nausea, cramping, coma, pulmonary edema, death
Hyponatremia Usually during prolonged exercise
Do not consume > 1 L / hr.
Include some Na+
Include glucose facilitate glucose-sodium transport