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Chapter 5 Nutrition and Supplements
Chapter 5
Extended Lecture Outline
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Nutrition Basics
o Nutrition is the science of the substances that are found in food that are essential to life
o Major Roles of nutrients
 Growth, repair and maintenance of all tissues
 Regulation of body processes
 Production of energy
o Essential nutrients must be supplied by the diet
o Six Classes of nutrients
 Carbohydrates (CHO)
 Fats (Lipids)
 Proteins
 Water
 Vitamins
 Minerals
o Vitamins, minerals and water are micronutrients which are necessary for regulating normal body
functions
o Nutrient Dense Foods: Supply adequate amounts of vitamins and minerals in relation to caloric
value
o Junk Foods: Provide excessive calories from fat and sugar in relation to vitamins, and minerals –
not nutrient dense
Energy Sources
o Carbohydrates
 Body’s most efficient source of energy
 Intake should account for 55-70% of total caloric intake
o Sugars: simple (sugars) or complex (starch and most forms of fiber)
 Monosaccharides: Simple sugars found in fruit, syrups, honey and glucose (blood sugar)
 Disaccharides: Milk sugar (lactose), table sugar (sucrose) – combination of two
monosaccharides
 Amount of sugar eaten should account for less than 15% of the total caloric intake
o Starches
 Complex Carbohydrates
 Made up of long chains of glucose units
 Food sources include rice, potatoes, and breads
 Body cannot use starches directly from food sources for energy – broken down during
digestion and converted to glucose (glycolysis)
 Glucose that is not needed for immediate energy is stored s glycogen in the liver and
muscle cells
 Body can only store limited amounts of glucose as glycogen – extra amounts of glucose
is converted to body fat
o Fiber
 Two kinds of dietary fiber: Soluble and Insoluble
 Soluble fiber: oatmeal, legumes and some fruits
 Insoluble fiber: whole grain breads and bran cereals
 Fiber passes through the intestinal tract and adds bulk as it is not digestible
 Aids in normal elimination of wastes through the digestive tract
 Believed to reduce the risk of colon cancer and coronary artery disease
 Recommended amount of fiber in the diet 25 grams per day
o Fats
 Most concentrated source of energy
 Recommended daily intake should be limited to less than 30% of total calories with
saturated fat less than 10%
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Fats may be saturated or unsaturated
Unsaturated fat: Omega – 3 fatty acids (found in cold-water fish) have capability to
reduce likelihood of diseases such as heart disease, stroke and hypertension
 Trans fatty acids – physical properties of saturated fatty acids. Found in cookies,
crackers, dairy products, meats and fast food. Increase risk of heart disease by boosting
levels of bad cholesterol.
o Other fats
 Phospholipids and sterols represent the remaining 5 percent of fats
 Cholesterol is best know sterol
 Fat substitutes: Simplese and Olean, contain no cholesterol and 80% fewer calories than
similar products made with fat
o Proteins
 Make up the major structural components of the body
 Needed for growth, maintenance, and repair of all body tissues
 Protein intake should be around 12-15% of total calories
 Amino Acids: basic units that make up proteins, essential amino acids are obtained
through food
 No advantage to consuming more protein, the body must convert the excess to fat for
storage
 Protein supplementation is not necessary
 Increased physical activity increases a person’s need for energy, not necessarily for
protein
Regulator Nutrients
o Vitamins
 Thirteen vitamins have specific roles in the body (Table 5-1)
 Classified into fat-soluble (dissolved in fat and stored in the body) and water-soluble
(dissolved in watery solutions and are not stored)
o Fat-Soluble: Vitamins A, D, E, and K (found in fatty portions of food and in oils and stored in the
body’s fat)
o Water-Soluble: Vitamins C (asorbic acid), B-Complex (thiamin, riboflavin, niacin, B6, folate, B12,
biotin and pantothenic acid): Should be supplied in diet each day
o Antioxidants: Vitamin C, Vitamin E, and beta-carotene
o May prevent premature aging, certain cancers and heart disease
o Protects vital cell components from destructive effects of certain agents, including oxygen
o Vitamin Deficiencies:
 Vitamin deficiency diseases are rare
 Vitamin supplements can cause toxic effects if taken in large enough quantities (Table 51)
o Minerals (Table 5-2)
 Most minerals are stored in the body, especially in the liver and bones
 Have essential roles in the body and must be supplied by the diet
 Include Magnesium, sodium, potassium, iron, calcium, copper, zinc, iodine, fluorine, and
phosphorus
o Water
 Most essential of all the nutrients
 Accounts for approximately 60% of body weight – varies due to age and percent of body
fat by (+/- 10%)
 Adequate supply of water is necessary for:
 Energy production in all cells
 Assists with digestion and maintains proper environment inside and outside cells
 Temperature control
 Elimination of waste products of nutrient and body metabolism
 Average adult requires a minimum of 2.5 liters or about 10 glasses of water a day
o Electrolyte Requirements
 Sodium, chloride, potassium, magnesium and calcium are electrically charged ions
dissolved in body water
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 Electrolytes maintain the balance of water inside and outside the cell
 Electrolyte losses can produce muscle cramping and heat intolerance
 Thirst is not an indicator of hydration
Nutrient Requirements and Recommendations
o A nutrient requirement is the amount of the nutrient that is needed to prevent the nutrient’s
deficiency disease
o U.S. Recommended Dietary Allowances (US RDA) have been changed to Dietary Reference
Intakes (DRI’s)
o DRI’s include recommended intakes (RDA’s) and also tolerable upper intake levels (UL’s)
 RDA: help individuals meet their daily nutritional requirements
 UL’s: help individuals avoid harm from consuming too much of a nutrient
 EAR (Estimated Average Requirements): are the average daily nutrient intake level
estimated to meet the requirement of half the healthy individuals in a particular age group
 AI (Adequate Intake): the recommended average daily intake level based on
experimentally developed estimates of nutrient intake that are used when the RDA cannot
be determined (Appendix E)
o Food Labels
 In early 1990’s new format of labels with information in the form of percentages of daily
values based on a standard 2,000 calorie diet
o MyPlate (Figure 5-3)
 My Plate was introduced in 2011 by USDA to replace MyPyramid
 Balance Calories
 Foods to Increase
 Foods to Reduce
 MyPyramid was introduced in 2005 by USDA – replaces the Food Guide Pyramid
Dietary Supplements
o No scientific basis for ingesting levels of nutrients above the DRI levels. Exercise increases the
need for energy, not for proteins, vitamins and minerals
o Vitamin Supplementation
 Many athletes believe taking large amounts of vitamin supplements can lead to superior
health and performance
 A megadose of a nutrient supplement is essentially an overdose, as the amount far
exceeds the DRI
 Vitamin requirements do not increase during exercise
 If an athlete is not eating a well balanced diet, taking a multiple vitamin once a day would
be helpful
o Mineral Supplementation
 Calcium Supplements: Calcium most abundant mineral in the body, essential for bones
and teeth, muscle contraction and conduction of nerve impulses
 If calcium intake is too low to meet needs, the body can remove calcium from
the bones – leading to osteoporosis
 Calcium AI for young adults is 1,000 mg (an 8 ounce glass of milk contains 300
mg’s)
 High protein diets and alcohol consumption also increase calcium excretion
from the body
 Exercise causes calcium to be retained in bones
o Individuals that are lactose intolerant (dairy products upset their
stomachs, lack lactase enzyme to digest milk sugar) may need
supplementation
 Calcium supplementation may be necessary preferably as calcium carbonate or
citrate rather than phosphate
o Iron Supplements
 Iron is needed to properly form hemoglobin
 Anemia (iron deficiency) reduces the oxygen carrying ability of the red blood cells, so
muscles cannot obtain enough oxygen to generate energy.
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 Supplementation according to the DRI may be required
Protein Supplementation
 To build muscles, athletes should consume 1-1.5 grams of extra protein per kilogram (0.5
– 0.7 grams per pound) of body weight every day
 An active adult will most likely require 0.6 gram per pound or 66 percent more than the
DRI
Creatine Supplementation
 Creatine is a naturally occurring organic compound synthesized by the kidneys, liver and
pancreas
 Creatine also obtained from eating meat and fish that contain approximately 5 grams per
kilogram
 Integral role in energy metabolism
 Two Types of Creatine
 Free Creatine
 Phosphocreatine (Stored in skeletal muscle and used during anaerobic activity to produce
ATP with assistance from enzyme creatine kinase)
 Phosphocreatine (Stored in skeletal muscle and used during anaerobic activity to produce
ATP with assistance from enzyme creatine kinase)
 Physiological effects
 Increases resynthesis of ATP; allows for increased intensity in a workout
 Functions as lactic acid buffer; prolongs maximal effort and improving exercise
recovery time during maximal intensity activities
 Stimulates protein synthesis
 Decreases total cholesterol; improving HDL-to-LDL ratio
 Decreases total triglycerides
 Increases fat-free mass
 Side Effects
 Weight Gain, gastrointestinal disturbances and renal dysfunction
 No long-term side effects noted
 Dosage
 Loading phase – ingest .3 grams per kilogram of bodyweight per day, dosage
should be split over 4-5 times per day with approximately 16 ounces of water
 Loading phase lasts for 5 days
 After loading phase for maintenance should take .03 grams per kilogram of
bodyweight for a month
 Wash-out phase – No supplementation for 1 month
 August 2000, NCAA Committee on Competitive Safeguards and Medical Aspects of
Sports banned distribution of all muscle-building substances, including creatine by
NCAA institutions. The use of creatine itself is not banned.
Herbal Supplements (Focus Box 5-1)
 Herbs are used as alternatives to drugs and medicines
 Herbs can offer the body nutrients that are reported to nourish the brain, glands and
hormones
 Herbs do not need to be taken with food as they provide their own digestive enzymes
 Herbs are not drugs but rather are body balancers that work with the body’s functions so
it can heal and regulate itself
 No federal or governmental controls regulating sales
 Using Ephedrine
 Ephedrine is a stimulant used in diet pills, illegal recreational drugs and
legitimate over-the-counter medications to treat congestion and asthma
 Similar to an amphetamine
 December 2003, FDA banned the use of ephedrine as a dietary supplement
 NCAA, NFL, NBA, minor league baseball and the
USOC have banned the use of ephedrine
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Adverse reactions: heart attack, stroke, tachycardia, paranoid psychosis, depression,
convulsions, fever, coma, vomiting, palpitations, hypertension and respiratory depression
o Glucose Supplements
 Ingesting large quantities of glucose (honey, candy bars, or pure sugar) immediately
before physical activity may have significant impact on performance
 The increase in glucose (blood sugar) stimulates the release of hormone insulin
 Insulin allows cells to use the circulating glucose so that blood sugar levels soon return to
normal
 Recent evidences indicates that eating large quantities of CHO’s is beneficial
Eating and Drinking Practices
o Caffeine Consumption
 Caffeine is a central nervous system stimulant
 Large amounts of caffeine cause nervousness, irritability, increased heart rate and
headaches
 Caffeine enhances the use of fat during endurance exercise, thus delaying the depletion of
glycogen stores – this delay would help endurance performance
 Caffeine also makes calcium more available to the muscle during contraction – allows
muscle to work more efficiently
 Olympic officials consider caffeine a drug and may not be found in a competitors blood
level greater than that resulting in drinking 5-6 cups of coffee
o Alcohol Consumption
 Each gram of pure alcohol (ethanol) supplies seven calories
 Sources of alcohol supply little nutritional value
 Effects of Alcohol
 Depressant effects on CNS – decreased physical coordination, slowed reaction times and
decreased mental alertness
 Increases production of urine – diuretic effect
o Eating Organic, Natural or Health Foods
 Organic foods are grown without the use of synthetic fertilizers and pesticides
 All foods (except water) are organic – they contain the element carbon
 No advantage to consuming organic food products
 Natural Foods are subjected to little processing and contain no additives such as
preservatives or artificial flavors
 Processing can protect nutritional value
 Preservatives save food that would otherwise spoil
o Vegetarianism
 Vegetarians use plant foods to form the foundation of their diet; animal foods are either
totally excluded or included in a variety of eating patterns
 Total vegetarians or vegans: Consume plant but no animal foods; meat, fish,
poultry, eggs and dairy products are excluded from their diet
 Lactovegetarians: Consume milk products along with plant foods; meat, fish,
poultry and eggs are excluded from their diet
 Ovolactovegetarians: Consume dairy products and eggs in their diet along with
plant foods; meat, fish, and poultry are excluded
 Semivegetarians: Consume animal products but exclude red meats.
o Pre-event Nutrition
 The importance and content of the pre-event meal has been heatedly debated among
coaches, athletic trainers, and athletes.
 The trend has been to ignore logical thinking about what should be eaten before
competition and to upholding the tradition of “rewarding” the athlete for hard work by
serving foods that may hamper performance. For example, the traditional steak-and-eggs
meal before football games is great for coaches and athletic trainers; however, the athlete
gains nothing from this meal.
 The important point is that too often people are concerned primarily with the pre-event
meal and fail to realize that the nutrients consumed over several days before competition
are much more important than what is eaten three hours before an event.
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The purpose of the pre-event meal should be to maximize carbohydrate stored in the
muscles as well as blood glucose.
 It has been suggested that the athlete consume carbohydrates 3-4 hours prior to practice
or competition. But it has also been suggested that consuming carbohydrates immediately
prior to competition causes an increased release of insulin, which increases the rate at
which muscles burn carbohydrate thus lowering blood glucose levels (hypoglycemia).
 Different carbohydrates are digested and absorbed at different rates. The glycemic index
(GI) is a scale that indicates the how much different types of carbohydrate effects blood
glucose levels.73
 Consuming foods that have a low to medium GI prior to an event is recommended
because they produce only small fluctuations in blood glucose and insulin levels and
release energy more slowly over a longer time period.
 Ingesting carbohydrates that have a high GI within an hour of exercise may actually
lower blood glucose. (Figure 5-4) lists the glycemic index range for common foods.
 Additionally the foods selected should minimize gastrointestinal distress, and should be
foods that the individual athlete prefers. It is also critical to make certain that the athlete
is appropriately hydrated.
Liquid Food supplementation
 Recently (Gatorade nutrition shake, exceed) have been recommended as effective preevent meals
 Supplements supply 225-400 calories per average serving
 Athlete’s using these supplements report elimination of usual pre-game symptoms of dry
mouth, abdominal cramps, leg cramps, nervous defecation and nausea
 Advantage of liquid supplements is that they clear both the stomach and the upper bowel
before game time, thus making available the caloric energy that would otherwise still be
in an unassimilated state
Eating Fast Foods (Table 5-3)
 Biggest concern of eating fast foods is 40-50% of the calories consumed are from fat
 More fast food restaurants have broadened their menus to include better food choices
such as whole wheat breads and rolls, salad bars, and low-fat milk products
 Selecting fast foods (Focus box 5-3)
Low Carbohydrate Diets
 Many different versions, all of which recommend a strict reduction in the consumption of
carbohydrates
 Replace carbohydrates with a high fat and moderate protein
 Overweight individuals became overweight due to a condition called hyperinsulinemia
(elevated insulin levels in the blood)
 Restricting CHO intake puts the body into a state of ketosis in which blood glucose levels
stabilize, insulin level drops, and because the body is burning fat, fairly rapid weight loss
occurs
Glycogen Supercompensation
 Maximizing the amount of glycogen that can be stored can be beneficial for endurance
events
 Athletes can increase glycogen supplies in muscle and liver by reducing the training
program a few days before competing and by significantly increasing CHO intake during
the week before the event (glycogen supercompensation)
 Reducing training for at least 48 hours before competition can eliminate any metabolic
waste products that may hinder performance
 High CHO diet restores glycogen levels in muscle and the liver
 The quantity of glycogen stored in the muscle directly affects the endurance of that
muscle
 Accomplished over a six day period divided into three phases
 Phase I: (days 1 & 2) training should be hard and dietary intake of CHO’s restricted
 Phase II: (days 3-5) training is cut back and the individual eats plenty of CHO’s
 Phase III: (day 6) the day of event – during which a normal diet must be consumed
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Only of value in long-duration events that produce glycogen depletion such as a
marathon
 Recommended not to be done more than 2-3 times a year
o Recommendations for Restoring Muscle Glycogen and Exercise
 When the time period between exercise sessions is relatively short (less than eight hours),
the athlete should begin consuming carbohydrates to restore supplies of muscle glycogen
as soon as possible after the workout to maximize recovery between sessions.
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Ideally the foods should have a high glycemic index.
 Given that complete muscle glycogen restoration takes at least twenty to twenty-four
hours, athletes should not waste time. They should ingest approximately 0.45 to 0.55
gram of carbohydrate per pound of body weight for each of the first four hours after
exercise or until they eat their next large meal.
 During this period, nutrient-rich carbohydrate foods, such as fruits and vegetables or a
high-carbohydrate drink, are recommended.
 Over a twenty-four-hour period, carbohydrate intake should range from 2.3 grams to as
much as 5.5 grams per pound of body weight, depending on the intensity of the activity.
 Pasta, potatoes, oatmeal, and sports drinks are recommended.
 It has been suggested that adding protein to a carbohydrate supplement enhances aerobic
endurance performance above that which occurs with carbohydrate alone, but the reason
for this improvement in performance has not been established.
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Most evidence supports a 4:1 carbohydrate to protein ratio, while others argue for a oneto-one or three-to-one ratio. Peanut butter and tuna are recommended as good sources of
protein.
o Fat Loading
 Some endurance athletes have used fat loading in place of CHO loading to have a better
source of energy at their disposal
 Deleterious effects outweigh any benefits
 Can cause cardiac protein and potassium depletion, causing arrhythmias and increased
levels of serum cholesterol
Body Composition and Weight Control
o Body Composition
 Ideal body weight often determined by age related height and weight charts – these charts
are inaccurate (involve broad ranges and often fail to take individual body types into
account)
 Body composition refers to both the fat and nonfat components of the body
 Percentage of body fat = the portion of total body weight composed of fat tissue
 Lean body weight = the total body weight that is composed of nonfat or lean tissue which
includes muscles, tendons, bones and connective tissue
 Average college-aged female has 20-25% of total body weight made up of fat and
average college-aged male has between 12-15%.
 Endurance female athletes 10-18% and males 8-12% body fat
 Body fat percentages should not go below 3% in males and 12% in females as the
internal organs tend to lose their protective padding of essential fat, potentially subjecting
them to injury.
 Obestiy – Excessive amount of fat, females over 30% and males over 20%.
 Two factors determine the amount of fat in the body – the number of fat or adipose cells
and the size of the adipose cell
 Adipose cells store triglyceride (a form of liquid fat) – the liquid fat moves in
and out of the cell according to energy needs
 The greatest amount of fat is used in activities of moderate intensity and long
duration
 One pound of body fat is made up of approximately 3,500 calories stored as
triglyceride within the adipose cell
o Assessing Body Composition
 Several methods are used: hydrostatic or underwater weighing, measurement of skinfold
thickness, and measurement of electrical impedance
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Skinfold technique measures the thickness of the subcutaneous fat layer with skinfold
calipers
 Accuracy is relatively low – error is plus or minus 3 – 5%
 Technique by Jackson and Pollack measures thigh, triceps, suprailiac,
abdominal, and chest
 Hydrostatic Weighing involves placing a subject in underwater tank to determine body
density
 Tank is expensive and technique is very time consuming
Bioelectrical impedance involves the measurement of resistance to the flow of electrical current
through the body between selected points
 Fat is poor conductor of electrical energy, and lean tissue is good conductor
 Impedance levels can be affected by levels of hydration – if dehydrated will
overestimate the percentage of body fat
 Equipment is fairly expensive
Determining Body Mass Index
 Use the persons body weight and height to calculate BMI
 BMI is ratio of body weight to height
 A BMI of 25-30 indicates that a person is overweight and a BMI over 30 equals obesity
Assessing Caloric Balance
 Caloric balance = Number of calories consumed (–) number of calories expended
 If more calories are consumed than expended = weight gain
 If more calories are expended than consumed = weight loss
Caloric Consumption or Intake
 Caloric balance is determined by the number of calories consumed regardless of whether
the calories are contained in fat, CHO, or protein.
 CHO = 4 calories per gram, Protein = 4 calories per gram, Fat = 9 calories per gram,
Alcohol = 7 calories per gram
 Estimations of caloric intake for college athletes = 2,000-5,000 calories per day
 Estimations of caloric expenditure range between 2,200 – 4,400 calories on average
Caloric Expenditure
 Calories may be expended in three different processes: Basal metabolism, work (defined
as any activity that requires more energy then sleeping), and excretion
 Specific energy expenditures can be determined by consulting charts that predict energy
used in an activity based on:
 Time spent in each activity in minutes
 The metabolic costs of each activity in kilocalories per minute per pound
(kcal/min/lb) of body weight
Methods of Weight Loss
 Weight loss through dieting alone is difficult and in most cases ineffective means of
weight control
 35-45% of weight decrease due to dieting results in loss of lean tissue
 Minimum caloric intake should not go below 1,000 – 1,200 calories a day for females
and 1,200 – 1,400 for males
 Weight loss through exercise involves an 80-90% loss of fat tissue with almost no loss of
lean tissue
 Most efficient method of weight loss is combination of diet and exercise
 Goal with any weight loss program is loss of 1.5-2 pounds per week, weight loss of more
than 4-5 pounds per week may be attributed to dehydration as opposed to body fat
Methods of Weight Gain
 Aim of weight gaining program is to increase lean body mass
 Recommend rate of weight gain is 1-2 pounds per week
 To gain one pound of muscle, an excess of approximately 2,500 calories is needed, to
lose one pound of fat, approximately 3,500 calories in excess of intake must be expended
in activities
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Adding 500-1,000 calories a day to the usual diet will provide energy needs of gaining 12 pounds per week
 Weight training must be a part of the weight gaining program
Disordered Eating
 Defined as spectrum of abnormal eating behaviors, ranging from mild food restriction
and occasional binging and purging, to severe conditions of bulimia nervosa and anorexia
nervosa
 Multi-factorial disorder includes social, familial, physiological and psychological
components
 Screening tests are now being used to detect eating disorders
 Types of eating disorders
 Bulimia Nervosa
o Commonly female ranging from adolescence to middle age
o 1-2% of population will develop bulimia nervosa, anorexia nervosa or
both
o Typically gorges self with thousands of calories after a period of
starvation and then purges self though induced vomiting and further
fasting or through use of laxatives or diuretics
o Typically is white, middle-upper class family, perfectionistic, obedient,
overcompliant, highly motivated, successful academically, well liked
by peers and a good athlete
o Commonly participates in gymnastics, track and dance, males included
in wrestling and gymnastics
o Binge-purge patterns can cause stomach rupture, disruption of hear
rhythm, liver damage, tooth decay from vomiting and chronically
inflamed mucous lining of mouth and throat
 Anorexia Nervosa
o 30-50% of individuals with anorexia nervosa will also develop some
symptoms of bulimia nervosa
o Characterized by distorted body image and a major concern about
weight gain
o 15-21% of individuals diagnosed with anorexia nervosa ultimately die
from the disorder
o Deny hunger, are hyperactive, engage in abnormal amounts of exercise,
and are highly secretive
o Getting the patient to realize they have a problem through treatment
and early intervention is the key to treatment
 Anorexia Athletica
o Condition specific to athletes characterized by several of the features
common to anorexia nervosa without the self-starvation practices
o Exhibit signs including: disturbance of body image, weight loss greater
than 5% of body weight, gastrointestinal complaints, primary
amenorrhea, menstrual dysfunction, absence of medical illness
explaining the weight reduction, excessive fear of becoming obese,
binging or purging, compulsive eating and/or restriction of caloric
intake
 Female Athlete Triad Syndrome
o Combination of an eating disorder (either bulimia or anorexia),
amenorrhea, and osteoporosis
o The major risk of this syndrome is that bone lost in osteoporosis may
not be regained
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