Unit 3-Energy, Exercise, and Body Weight//Unit 4- Water, Electrolytes, and Contaminants Flashcards
Unit 3: Energy, Exercise, and Body Weight
Universal currency of energy = ____
WHY do we need energy?
• To perform mechanical work
– Muscle contraction, cellular movement
• _____ ________of molecules and ions across
biological membranes
• Synthesis of _____________ from simple
precursors
ATP
Active transport
macromolecules
Unit 3: Energy, Exercise, and Body Weight
ATP Is the primary donor of ____ ______ for metabolic and other biochemical reactions
• ATP turnover is very high in the body; each molecule lasts about a minute before being consumed
• The total amount in the body is ~100g, however strenuous exercise consumes ______/MIN
• ATP regeneration must therefore be highly efficient!
–Carbon-containing fuel molecules like glucose or fats, are oxidized to CO2 and the energy release is used to convert ___ & _____ to ATP
free energy
~500g/min
ADP and PI
Unit 3: Energy, Exercise, and Body Weight
Energy from food is extracted in three stages
———— Stage 1:————————
• Large, complex molecules are broken down into usable units
• Fats are broken down to fatty acids and glycerol
• Polysaccharides are processed to glucose and other simple sugars
• Proteins are hydrolyzed to amino acids
• No energy is generated here!!!
STAGE ONE IS BASIC BUT KNOW….
No energy is generated here!!!
Unit 3: Energy, Exercise, and Body Weight
————–Stage 2:————————–
• Numerous small carbon compounds are degraded to a
common end product – ____________
• Some energy (ATP) is generated in this step, but some is also _________
Acetyl CoA
consumed
Unit 3: Energy, Exercise, and Body Weight
———————Stage 3:——————————–
• The acetyl group of acetyl CoA is completely oxidized to ______
•__________ are released, captured by intermediates (NAD+ and FAD), and used to power a proton
gradient that synthesizes large amounts of ATP
CO2
Electrons
Unit 3: Energy, Exercise, and Body Weight
The function of the citric acid cycle is to accept 2-carbon
fragments and ________ them to CO2
• This produces high-energy electrons that are then used to reduce molecular oxygen (O2) to water.
• Electrons are accepted by ____ &_____ to form NADH and FADH2
oxidize
NAD+and FAD
Unit 3: Energy, Exercise, and Body Weight
Energy Requirements = Dietary Energy Intake
• Required for growth or __________ in a person of
defined age, gender, weight, height, and physical activity
• In pregnant and lactating women, it includes the needs for deposition of tissue and production and secretion milk
• An ___OR_____ person needs may be increased or
decreased
maintenance
ill or injured
Unit 3: Energy, Exercise, and Body Weight
——-Total Energy Expenditure (TEE) or
Estimated Energy Requirement (EER)—————-
1—_____ _________ ______________ (BEE)
= _________ energy expenditure compatible with life
– Reflects the energy used over a 24 hour period while physically and mentally at REST and in a thermoneutral environment
– Measurement should be taken after sleep and 10-12 hours post-prandial
– ___% TO ____% of total energy expenditure (TEE)
Basal energy expenditure
Minimal
60% to 70%
Unit 3: Energy, Exercise, and Body Weight
——-Total Energy Expenditure (TEE) or
Estimated Energy Requirement (EER)—————-
2—_______ __________ OF ________ (TEF)
– Energy needed for consumption, digestion, and absorption of FOOD
– Accounts for about ____% of TEE
– Obligatory includes synthesis and storage
– Facultative thermogenesis is excess energy expended
– Affected by ____________ of the diet, eating schedule, and spices
Thermic effect of FOOD
10
composition
Unit 3: Energy, Exercise, and Body Weight
——-Total Energy Expenditure (TEE) or
Estimated Energy Requirement (EER)—————-
3—-__________ __________ (AT)
– Energy expended during sports or fitness exercise and activities of daily living
– Most variable component of ___
– Affected by body size, efficiency of individual habits of motion, and ______ _________
Activity thermogenesis
TEE
fitness level
Unit 3: Energy, Exercise, and Body Weight
Factors Affecting Resting Energy Expenditure (REE)
REE is used in place of BEE most often today, and are often used interchangeably. REE is usually __-___% higher than BEE.
Body size (direct prop)
• Body composition (direct prop with LBM)
• Age (indirect prop)
• Gender (M>W, 5-10%)
• Hormonal status
• Caffeine, nicotine, and alcohol (increases REE)
• Fever (increases REE by 7% per °F over 98.6 °F)
• Extreme environmental temperatures
***REE is measured using ______ ________ through the use of a ventilated hood system
10-20%
indirect calorimetry
Unit 3: Energy, Exercise, and Body Weight
Units of Energy Measurement • Kilocalorie (kcal)-----------1 kcal = \_\_\_\_\_\_ kj – Carbohydrate = 4 kcal/g – Protein = 4 kcal/g – Fat = 9 kcal/g – Alcohol 7 kcal/g
Kilojoule (kJ)—non–U.S. countries; the metric value
1 kj = energy req. to move 1 kg a distance of 1 m (using a force of 1 N)
– Carbohydrate = 17 kJ
– Protein = 17kJ
– Fat = 38 kJ
4.18
Unit 3: Energy, Exercise, and Body Weight
Measuring Energy Expenditure
1 •_____ calorimetry
– Measures amount of heat produced by the individual
– Very expensive!
2 • _______calorimetry
– Used in clinical practice, particularly in intensive care and burn units
– Equipment is known as metabolic cart or monitor
– Provides information on substrate utilization through the respiratory quotient (RQ)
3 • Doubly labeled water
– Using radiolabeled water,_____ production is measured, and then equated to TEE
Direct
Indirect
CO2
Unit 3: Energy, Exercise, and Body Weight
____ = Volume of CO2 EXPIRED/volume of O2
CONSUMED to metabolize a particular molecule
RQ values:
>1.0 = fat synthesis
1.0 = carbohydrate
0.85 = mixed diet
0.82 = protein
0.7 = fat
0.67 = alcohol
RQ
macronutrient(s)
Unit 3: Energy, Exercise, and Body Weight
_____ _____ ______= (TEE)
Age, weight, height and PA are the only variables
HEIGHT = METERS WEIGHT = KILOGRAMS AGE = YEARS PA = coefficient
Total Energy Expenditure
Unit 3: Energy, Exercise, and Body Weight
Macronutrients are __________
-produces energy when metabolized
ergogenic
Unit 3: Energy, Exercise, and Body Weight
———4 Focal Points————–
1 • Metabolic rate in the human body is affected by several variables, including daily TEE, two-thirds of which is the ______
2 • The energy cost of physical activity is the most variable of factors related to an individual’s______ and can be altered by the individual.
3 • Energy expenditure can be measured by several methods, but only ________calorimetry provides an RQ.
4 • Energy expenditure equations are commonly used with an activity factor to estimate energy needs.
BEE.
TEE
indirect
Unit 3: Energy, Exercise, and Body Weight
How much Carbs, Protein and Fat should you eat? Example: your TEE is 2,500 kcal/day 1----Percentage of kcal from Carbs: 60% Protein: 10% Fat: 30% Alcohol: 0 2---Atwater Coefficient--- CARBS--4.0 kcal/g PROTEIN--4.0 FAT--9.0 ALCOHOL--7.0 3---Carbs: (2500 kcal/day x 0.60)/4 kcal/g = 375 g/day Protein: (2500 x 0.10)/4 = 62.5 g/day Fat: (2500 x 0.30)/9 = 83.33 g/day
KNOW
Unit 3: Energy, Exercise, and Body Weight
Desirable Body Weight or Optimum Body Weight
1–• Balancing energy intake and energy expenditure
is the basis of ______ __________ throughout
life.
2—Intake > Expenditure = Normal growth, pregnancy,
obesity, recovery from illness, HYPOthyroidism
• Intake = Expenditure = Normal condition of healthy
adults
3–• Intake
weight management
diabetes mellitus and malabsorption
Unit 3: Energy, Exercise, and Body Weight
Theoretical Body Composition Model for a Man and Woman
1—Essential body fat—Necessary for physiologic
function. About ___% of body weight in men and __% in women
2–Storage body fat—Energy reserve under the skin,
primarily triglycerides in adipose tissue. Around the internal organs to protect them from trauma. Most considered expendable.
Good health associated with:
____-_____% of body weight in MEN
_____-______% in WOMEN
3
12
10% to 25%
18% to 30%
Unit 3: Energy, Exercise, and Body Weight
Body Mass Index (BMI)
• BMI = weight / height2 (kg/m2)
• General comparison between body wt and _____
BMI RANGE FOR MEN AND WOMEN 18.5 – 24.9 Normal 25 – 29.9 Overweight 30 – 34.9 Obese 35+ Clinically obese
health
Unit 3: Energy, Exercise, and Body Weight
Methods of Measuring Obesity 1 • BMI-----------Know the cutoffs!! 2 • Waist circumference: > \_\_ inches in men > \_\_ inches in women 3 • Waist-to-hip Ratio (WHR): > 0.85 in men > 0.73 in women ****Varies according to race and age. Older people are allowed higher WHR, younger less
40
35
Unit 3: Energy, Exercise, and Body Weight
Etiology of Obesity X 11
1 • Heredity—obesity gene? Twins show genetic component
2 • Imbalance of intake versus output
3 • Lack of exercise
4 • Sleep, stress, and circadian rhythms
– Chronic sleep deprivation
– Cortisol
5 • Set point Theory:body maintains its normal weight and body fat level with internal regulatory controls that dictate how much fat one has!!
6 • Thermic Theory: low level of brown adipose tissue. Less futile cycles into heat
7 • Psychological: tendency to eat when depressed
8 • Adipocyte Theory:_______ obesity increases adipocyte number!!
9 • Socioeconomic: Affordability and availability of food
10 • Cultural: Feasting, etc
11 • Lifestyle: Snacks, football Sunday, etc
Infant
MOST IS COMMON SENSE
Unit 3: Energy, Exercise, and Body Weight
Etiology of Obesity: Set point Theory
• Idea: The body has a mechanism to regulate its fat
size
• Evidence: Humans and animals can restore normal
body weight when allowed to eat freely after ________ OR_________.
• Mechanism: Unknown. Blood levels of a group of
peptides are being investigated for their effects on
appetite.
starvation or forced feeding.
Unit 3: Energy, Exercise, and Body Weight
Appetite Altering Peptides:Orexigenic Peptides Orexigenic: Peptides that INCREASE appetite
– Agouti-related peptide
– Neuropeptide Y
– Melanin Concentrating Hormone (MCH)
– Orexins (hypocretins)
ALL FOUR RELEASED BY ____________-
BRAIN
Unit 3: Energy, Exercise, and Body Weight
Appetite Altering Peptides:Orexigenic Peptides Orexigenic: Peptides that INCREASE appetite
– Insulin
RELEASED BY??
PANCREAS
Unit 3: Energy, Exercise, and Body Weight
Appetite Altering Peptides:Orexigenic Peptides Orexigenic: Peptides that INCREASE appetite
Ghrelin
RELEASED BY??
STOMACH
**Blood ghrelin is lowest after a meal, rises prior to next meal
Unit 3: Energy, Exercise, and Body Weight
Appetite Altering Peptides:Anorexigenic Peptides
Anorexigenic: Peptides that DECREASE appetite
– ______ ________: blocks ghrelin
– _______ ________: delays stomach emptying, acts on satiety center in brain
– Cholecystokinin
ALL RELEASED BY INTESTINE!!
Peptide YY
***Injection with Peptide YY decreases appetite in humans
Glucagon-like peptide
Unit 3: Energy, Exercise, and Body Weight
Appetite Altering Peptides:Anorexigenic Peptides
Anorexigenic: Peptides that DECREASE appetite
– Melanocortin: binding R inhibits intake
RELEASED FROM WHAT ORGAN??
BRAIN
Unit 3: Energy, Exercise, and Body Weight
Appetite Altering Peptides:Anorexigenic Peptides
Anorexigenic: Peptides that DECREASE appetite
Leptin: regulates intake of kcal, C, F, but not percentages of each. Does not prevent obesity!!!
RELEASED BY??
Adipocyte
Unit 3: Energy, Exercise, and Body Weight
Brain Neurotransmitters
• Norepinephrine and dopamine —released by sympathetic nervous system in response to dietary intake»_space;» mediates hypothalamus = _______ food intake
• Fasting and semistarvation decrease levels of
these neurotransmitters = __________ food intake
decreased
increased
Unit 3: Energy, Exercise, and Body Weight
OBESITY Health Risks and Longevity Diabetes • Heart disease • Hypertension • Hyperlipidemia • Gallbladder disease • Some cancers • Nonalcoholic fatty liver disease (NASH) • Atherosclerosis • Respiratory insufficiency & sleep apnea • Joint diseases / arthritis • Metabolic Syndrome
DON’T GET FAT!!
Unit 3: Energy, Exercise, and Body Weight
———Metabolic syndrome (MetS)———–
• Includes three or more of the following:
1 – Waist circumference >102 cm (40 in) in men and >88 cm
(35 in) in women
2 – Serum triglycerides of at least ____ mg/dL
3 – High-density lipoprotein (HDL) level
150
135/85
Unit 3: Energy, Exercise, and Body Weight
NIH recommends loss of ________/wk for BMI 27 to
35; 1 to 2 lb/wk for BMI >35
***1lb ~3500 kcal
0.5 to 1 lb
Unit 3: Energy, Exercise, and Body Weight
Physical Activity X 7
1 • Increases proportion of LBM to fat
2 • Offsets decrease in RMR with weight loss
3 • Strengthens cardiovascular integrity
4 • Increases sensitivity to insulin
5 • Expends more energy
6 • ______ TO ___ min/day recommended for weight loss (at least 30 minutes; moderate intensity)
– Ideal intensity: 60-80% VO2 max or ___-___% max heart rate (Max heart rate is approximately 220-age)
7 • Aerobic and resistance training
60 to 90
70-85
Unit 3: Energy, Exercise, and Body Weight
Surgical Procedures
• Bariatric surgery—for morbidly obese only; BMI ___
or above—Should have tried and failed with numerous weight-management plans—Gastric resection
• Jaw wiring
• Liposuction
• NIH suggests dietary, exercise and behavior
modifications for __+ months prior to any of these procedures
45
6
Unit 3: Energy, Exercise, and Body Weight
Focal Points x 4
1 • Overweight and obesity in adults (____ %) in the United States have reached epidemic numbers. Even more alarming is the increasing rate (.____%) of overweight in children and adolescents. The United States is not alone in terms of trends; they exist worldwide.
2 • Obesity has severe associated risks: type 2 diabetes, hypertension, atherosclerosis, some cancers, sleep apnea, infertility, gallbladder disease, and liver disease; increased visceral fat has an important influence on metabolic and cardiovascular risk factors.
3 • A chronic disease model involving both caloric restriction, increased physical activity and lifestyle interventions in the context of an interdisciplinary
approach offers the best treatment options for the patient.
4 • Stopping weight gain or achieving a moderate loss should be promoted as a treatment goal; an achievable __% to __% loss of initial body weight can improve glycemic control, blood pressure and lipid profile in most patients
- 3%
- 1
5–10%
Unit 3: Energy, Exercise, and Body Weight
Anorexia Nervosa
1 • A disease characterized by:
– Refusal to maintain a minimally normal body weight
– Body image distortion
– Amenorrhea in postmenarchal females
2 • May be one of two subtypes
a – Restricting
b – Binge eating and purging
3 • Prevalence of disease
– 0.3% to _____% of women; rate is about one-tenth in men
– Initial presentation is usually during adolescence or young adulthood
– Genetic, environmental, and psychosocial factors
– ___—_____% of patients die
3.7%
5–25%
Unit 3: Energy, Exercise, and Body Weight
Clinical Characteristics and Medical Complications
—-Anorexia nervosa—–
– Cachectic and prepubescent body habitus
– Lanugo: dry and brittle hair
– Hypercarotenemia
– _______ intolerance, cyanosis of the extremities
– PEM and cardiovascular complications
– __ complications
– Osteopenia
– Effects on growth and development in children and
adolescents
cold
GI
Unit 3: Energy, Exercise, and Body Weight
——-Bulimia Nervosa——-
• Characterized by repeated episodes of binge eating
followed by inappropriate compensatory behaviors to
prevent weight gain
– Self-induced vomiting, laxatives misuse, diuretic misuse,
________ ______________, or fasting
• ___% to ___% of adult women
• Binge = consumption of an unusually large amount of
food in a discrete period
• Psychiatric comorbidities
compulsive exercise
1–3%
Unit 3: Energy, Exercise, and Body Weight
Clinical Characteristics and Medical Complications of Bulimia Nervosa
• Usually ________ weight and __________ behavior
• Signs of self-induced vomiting (Russell’s sign)
• Results of chronic vomiting can include esophagus and
stomach damage
• Effects of laxative and diuretic abuse include electrolyte imbalance and cardiac arrhythmia.
normal
secretive
Unit 3: Energy, Exercise, and Body Weight
Physical Signs and Symptoms of Anorexia Nervosa and
Bulimia Nervosa
SEE SLIDE 58 AND PRINT FOR SEMINAR USE!!
Unit 3: Energy, Exercise, and Body Weight
“OTHER” DISORDERS
1—Eating Disorder Not Otherwise Specified (EDNOS)
– A diagnostic category for eating disorders that meet most, but not all, criteria for either anorexia nervosa or bulimia nervosa
2—• ______ _________ Disorder
– Characterized by binge-eating episodes at least twice a
week for a 6-month period
– No inappropriate compensatory behaviors after a binge
– Occurs in late adolescence
– Emotional distress and feeling of powerlessness
– Most are overweight
– Night eating syndrome and sleep disorders
Binge-eating
***Treatment includes inpatient hospitalization, residential treatment, day hospitalization, intensive outpatient treatment, and outpatient treatment
Unit 3: Energy, Exercise, and Body Weight
Psychotherapeutic Treatment
- Behavioral reinforcement
- Psychotherapy, cognitive-behavioral therapy, family or marital therapy
- Assessment instruments
- Treatment usually 1 year or more
- Compared with anorexia, bulimia patients are generally more open to ___________
- ___________, separation anxiety, and generalized anxiety must also be treated
Depression
intervention
Unit 3: Energy, Exercise, and Body Weight
Nutrition Assessment
• Laboratory assessment
• Vitamin and mineral deficiencies
– Hypercarotenemia, iron deficiency anemia, osteopenia, and osteoporosis
• Fluid and electrolyte balance
– Significant problems with vomiting and laxative and diuretic abuse
• Energy expenditure
– Low ____ in anorexia; unpredictable in bulimia
• ________________ assessment
REE
Anthropometric
Unit 3: Energy, Exercise, and Body Weight
Prognosis
• Relapse in anorexia: up to ____% of patients require
rehospitalization
• Enduring morbid food and weight preoccupation
• Outcomes are better in ___________patients
• High mortality rates associated with___________
• Relapse in __________ high
50%
younger
anorexia
bulimia
Unit 3: Energy, Exercise, and Body Weight
Focal Points
• Anorexia nervosa and bulimia nervosa must be understood and appreciated as potentially _______disorders characterized by periods of ________
• Refeeding in eating disorders requires the ___________ effort of medical and mental heath professionals with the support of friends and family.
• Nutrition rehabilitation can correct some (i.e., hypometabolic state, vital sign instability) but NOT all (organ mass, bone mass, and growth) of the pathophysiologic consequences of malnutrition in eating disorders.
• Successful long-term treatment can take _______, and the expectation of a quick cure should be dispelled.
chronic
relapse.
collaborative
years
*****HELP: www.anad.org National Association of
Anorexia Nervosa and associated disorders
1.847.831.3438
Unit 4: Water, Electrolytes, and Contaminants
__________________ involves the gastrointestinal (GI) tract, kidneys, and brain working together
Homeostasis
Unit 4: Water, Electrolytes, and Contaminants
Distribution of Body Water X 3
1–Water content of the fat-free body mass is remarkably __________
2–Extracellular water (ECW) ~___% BW
– Plasma, lymph, spinal fluid, secretions
3—Edema: abnormal accumulation of fluid in interstitial
spaces. AKA “______ ________”
constant.
20%
Third spacing
Unit 4: Water, Electrolytes, and Contaminants
Water Balance
- Daily INTAKE is equivalent to LOSSES
- Thirst control centers are in ventromedial and ______ __________ near ADH (vasopressin) regulating centers
- Kidneys release ____ to produce angiotensin II=thirsty
anterior hypothalamus
renin
Unit 4: Water, Electrolytes, and Contaminants
Metabolic water:
oxidation of 100 g of fat, carbohydrate, and protein yields 107, 55, and 41 g of water or about_______TO_________ mL/day
200 to 300
Unit 4: Water, Electrolytes, and Contaminants
Water Elimination
1–___________water loss: via kidneys as urine and via GI tract in feces. Kidney is primary regulator of sensible water loss.
2—_________ water loss: air expired from lungs and
water vapor lost through the skin
Sensible
Insensible
Unit 4: Water, Electrolytes, and Contaminants
Water Balance – Water elimination
1—Water elimination
– GI tract: __-___ L of digestive juices / day
– All but ~100 mL is reabsorbed by ileum and colon
2—Older people have a harder time, increasing risk
of dehydration and hypernatremia (Hypernatremia is generally not caused by an excess of sodium, but rather by a relative deficit of free water in the body. For this reason, hypernatremia is often synonymous with the less precise term, dehydration.)
7–9
Unit 4: Water, Electrolytes, and Contaminants
Reabsorption along the Nephron
1---Water reabsorbed at the: • Proximal convoluted tubule (\_\_-\_\_\_\_%) • Loop of Henle (~5%) – Thin descending 2--- NONE at • Thin ascending • Thick ascending • Early distal convoluted tubule (macula densa)
65-75
Unit 4: Water, Electrolytes, and Contaminants
Function of the Kidney:
Filtration:
1–Electrolytes such as sodium, chloride, bicarbonate
are highly _______. Very little appears in the urine.
2—Nutritional substances, such as amino acids & glucose
________ reabsorbed from the tubules. Very little/none appears in the urine even though large amounts are filtered by glomerular capillaries
3—Waste products:Urea & ___________
4—Electrolytes: Sodium Chloride
5.—Nutritional: Amino acids & Glucose
6—Organic: Acids & Bases
reabsorbed
completely
Creatinine
Unit 4: Water, Electrolytes, and Contaminants
Signs of dehydration: headache, fatigue, decreased
appetite, lightheadedness, poor skin turgor,
concentrated urine, decreased urine output, sunken
eyes.
—-Loss of ___-____% body water reduces muscle work
capacity by 20-30%
4–5%
Unit 4: Water, Electrolytes, and Contaminants
Water Requirements
1—-No storage of water occurs
2—(~ 0.5 oz/lb adults, 1 oz/lb kids, 2.5 oz/lb infants)
3—Usually about ____ L for males and 2.7 L for females
4—The FNB has NOT established an upper limit (UL) on water intake,
3.7
Unit 4: Water, Electrolytes, and Contaminants
Water intoxication – 2 types
- Excessive intake of water—Increases _____ volume and cells swell. Swelling of brain = headache, nausea, vomiting, muscle twitching, convulsions, stupor, coma, death
- Intake of water without Na+–in re-hydration More K+ moves to outside of cells Hypotension, convulsions, muscle cramps. Death reported in marathon runners
- water w/o Na+ = ___________
intracellular
hyponatremia
Unit 4: Water, Electrolytes, and Contaminants
Deficiency of Water – Consequences
- Impairs food ingestion, digestion, absorption
- Impairs blood ______, transport of nutrients and metabolic wastes
- Hypotension
- Impairs regulation of body temperature
- Constipation
- Reduced________________, in general
- Impairs physical performance
circulation
metabolism
Unit 4: Water, Electrolytes, and Contaminants
Electrolytes
• Compounds that dissolve into cations and anions in
water
• Sodium, potassium, magnesium, chloride, and other
compounds
•______________ electrolytes: sodium, calcium, chloride,
and bicarbonate (HCO3-)
• ________ electrolytes: potassium, magnesium, and
phosphate
• Maintain physiologic body functions: osmotic equilibrium, acid–base balance, and intracellular and
extracellular concentration differentials
Extracellular —SCC
Intracellular —-PMP
Unit 4: Water, Electrolytes, and Contaminants
Electrolytes – Table salt = 2/3 tsp
1–• FNB: ____g/ day (1.5g Na+, 2.3g Cl-)
To replace amount lost in sweat and get enough dietary
2—• UL: _____ g / day
– 90% men consume excess
– 75% women consume excess
- 8
5. 8
Unit 4: Water, Electrolytes, and Contaminants
Sodium
• Major CATION (+) of ECF
• 35% to 40% of total Na+ is in ______ and NOT very available
• Sweat is actually_________ contains little Na+
• Na+ regulates ECF and plasma volume, nerve impulses, and muscle contraction
• Readily absorbed from intestine and carried to the kidneys, where it is filtered and then returned to the bloodstream
• ____-____% of normal loss occurs through urine; rest is
from feces and sweat
• Balance is maintained through aldosterone (mineralocorticoid) from adrenal cortex
– Blood Na+ INCREASE = thirst receptors in hypothalamus stimulated = thirsty!!!
– Estrogen acts similar to aldosterone = Na+ and H2O retention
KEY———• AI ~ 200 mg/day, mean intake is 4 to 5 g/d; recommended is ___ g/d, UL is ____ g/d
skeleton
hypotonic;
90% to 95%
- 5 OF SODIUM
- 3 OF SODIUM
Unit 4: Water, Electrolytes, and Contaminants
Chloride
- Major ANION (-) of ECF
- Maintains _______ ________ and osmotic pressure along with Na+
- High concentrations in cerebrospinal fluid and gastric/pancreatic fluids
- Absorbed in intestine; excreted in urine and perspiration
- Recommended intake: _____ g/d
water balance
2.3
Unit 4: Water, Electrolytes, and Contaminants
Magnesium
• SECOND most prevalent ___________ CATION (+)
– Only about 1% of total Mg2+ is ___________
• About ½ of total Mg2+ is stored in BONE
• Important COFACTOR in many enzymatic reactions
• Important in bone metabolism, central nervous system,
cardiovascular function
• High Magnesium levels in green leafy veggies
• Recommended intake: ______-________ mg/d
intracellular
extracellular
300-400
Unit 4: Water, Electrolytes, and Contaminants
Calcium
- ___% in bone (hydroxyapatite, Ca5(PO4)3(OH));remaining __% has important physiologic functions
- Second messenger after binding of hormones or proteins to cell surface (first messenger)
- Ca2+ content REGULATED by ________ hormone (stim absorp in GI and release from bones) , CALCITONIN (decrease absorp in GI and release from bones) , VITAMIN D (stim absorp in GI), and phosphorous (inhibits absorp in GI)
99
1
parathyroid
Unit 4: Water, Electrolytes, and Contaminants
Calcium
- Regulates cell _______________
- Blood clotting
- ~20% to 60% of dietary calcium is absorbed; tightly regulated to maintain steady serum calcium levels
- The ________ are the main source of excretion; about 100 to 200 mg is excreted in normal adult urine
- Recommended intake ranges from ______TO______ mg/day depending on age and gender; upper limit is about ______ mg
electroconductivity
kidneys
1000 to 1300
2500
Unit 4: Water, Electrolytes, and Contaminants
Phosphorus
- Important constituent of intracellular fluid
- 80% of P found in__________Ca5(PO4)3OH
- Role in energy metabolism in adenosine triphosphate (ATP)
- Phosphorylation reactions in cell
- Buffer in ___-_____ balance
- Cellular structure in phospholipid membrane
- Found in animal products and some dried beans
- Recommended intake: __________/d
bones
acid–base
700 mg
Unit 4: Water, Electrolytes, and Contaminants
Potassium
• Major cation of _______
• Normal water balance, osmotic equilibrium, acid–base
balance (along with Na+), neuromuscular activity (along
with Ca2+), cellular growth (needed for muscle formation)
• Readily absorbed from small intestine
• Mostly excreted from urine (80-90%)
• Widely distributed in foods; protective against high blood pressure
• AI: ________/day
– To lower BP, blunt effects of salt, reduce risk of kidney
stones
• Most Americans consume
ICF
4.7g
50%
Unit 4: Water, Electrolytes, and Contaminants
Sources of Potassium: widely distributed in foods' ----------Excellent foods (> 300 mg)-------------- • Potatoes (sweet) • Squash • Dry beans • Corn • Artichoke • Tomato • Spinach • Avocado • Banana • Mango • Papaya • Cantaloupe • Yogurt
know
Unit 4: Water, Electrolytes, and Contaminants
Acid–Base Balance
• Acid–base balance is the dynamic state of equilibrium of H+ concentration
• Maintaining the pH level within a normal range of
_____to______ is crucial for many physiologic functions and biochemical reactions (kidneys, lungs, buffers)
• Acids generated from ingestion and metabolism of food and toxins
• Intracellular buffers: _____and_______________
extracellular buffers: _____________and__________-
7.35 to 7.45
proteins and phosphates
bicarbonate and carbonic acid
Unit 4: Water, Electrolytes, and Contaminants
4 Major Acid–Base Imbalances and Possible Etiologies
1 of 4–_____________ ___________________
DISEASE = Conditions involving decreased lung surface area, such as emphysema. Restrictive or obstructive lung diseases. Certain neuromuscular disease in which
respiratory function is impaired.
Respiratory acidosis
Unit 4: Water, Electrolytes, and Contaminants
4 Major Acid–Base Imbalances and Possible Etiologies
2 OF 4-___________ _____________
DISEASE = Aftermath of intense exercise. Anxiety reaction. Early sepsis
-Respiratory alkalosis
Unit 4: Water, Electrolytes, and Contaminants
4 Major Acid–Base Imbalances and Possible Etiologies
3 OF 4 —________ ____________
Diarrhea Uremia Ketoacidosis from uncontrolled diabetes mellitus Starvation High-fat, low-carbohydrate diet Drugs
Metabolic acidosis
Unit 4: Water, Electrolytes, and Contaminants
4 Major Acid–Base Imbalances and Possible Etiologies
4 OF 4 ___________ ______________
Diuretics use
Increased ingestion of alkali
Loss of chloride
Vomiting
Metabolic alkalosis
Unit 4: Water, Electrolytes, and Contaminants
Metabolic X 2
__________: increased generation of accumulated acids (diabetes ketoacidosis, lactic acidosis) or bicarbonate losses from the kidneys or GI tract
Acidosis
Unit 4: Water, Electrolytes, and Contaminants
Metabolic X 2
_________: administration or accumulation of
bicarbonate, excessive acid loss (nasogastric
suctioning), or loss of ECF as from diuretics
Alkalosis
Unit 4: Water, Electrolytes, and Contaminants
Respiratory X 2
_________: decreased ventilation and consequent CO2 retention, as in sleep apnea, asthma, aspiration of
foreign object, COPD, and ARDS
Acidosis
Unit 4: Water, Electrolytes, and Contaminants
Respiratory X 2
__________: increased ventilation and elimination of CO2, as in head injury, CHF, pneumonia, and hypoxemia
Alkalosis
Unit 4: Water, Electrolytes, and Contaminants
1 • Body tries to ________ normal pH by developing
compensatory responses to offset the effects of primary
disorder
– Ex. If respiratory acidosis, then kidneys INCREASE HCO3 -reabsorption, creating a metabolic alkalosis to INCREASE pH.
– Ex. If metabolic acidosis, then lungs INCREASE ventilation and CO2 elimination, creating a respiratory alkalosis to INCREASE pH.
• MUST distinguish between primary and secondary
disturbances
• Treat according to _______ problem and its underlying
cause
• Respiratory compensation takes ______, Metabolic
compensation takes ___________
restore
primary
minutes
3-5 days
Unit 4: Water, Electrolytes, and Contaminants
Focal Points
1 • Acid–base patterns often serve as a common diagnostic tool within medical specialties (Whittier & Rutecki, 2004).
2 • Despite wide daily variations in intake of water and minerals that function as electrolytes, the body strives to maintain a stable internal environment to maintain ____________ ______________
3 • When normal homeostatic mechanisms are rendered ineffective by _________OR _______ or when intakes exceed the body’s normal regulatory capacities, the internal environment and ultimately cell function are disrupted.
4 • ALL changes in _______ _____ in health and in disease occur in carbon dioxide, electrolyte concentrations, and total weak acid concentrations (Kelllum, 2005).
5 • Knowledge of fluid, electrolyte, and acid–base balance is important for understanding many aspects of nutrition in ________AND _________.
physiologic functioning.
disease or injury
blood pH
health and disease
