Unit 8: Metabolism of Nutrients And Energy Balance

Question 1

How many caries does carbs fat/lipid and protien give

Answer 1

Carb: 4 cal/g

Fat (lipid): nine

protein: 4

Question 2

What are gross food energy values measured in

How

Answer 2

A bomb calorimeter

Determines the energy in food by measuring the heat released after complete burning of the food

Question 3

Is the energy extracted from food the same as the gross food energy value and why?

How can the gross energy values be adjusted?

Answer 3

The energy extractor from food is less than the gross food energy value

This is because of incomplete digestion, absorption and metabolism, causing a small amount of the energy value in the food to be lost and excreted in the faeces or urine

They can be adjusted to represent the energy actually given to the body , these are called physiological, fuel, values, or energy nutrients

Question 4

What are physiological fuel values?

Answer 4

The adjusted gross energy values to represent the energy, actually available to the body

This is the calories for carbs (4) for lipids (9) and proteins (4) and alcohol (7) in kcal/g

Question 5

Where do energy values in food composition tables come from?

Answer 5

They come from the physiological fuel values based on the chemically determined contents of carbohydrates, lipids, proteins, and alcohol present in the foods

Question 6

What happens when more food energy is consumed than needed

What is the equation for the daily energy balance?

Answer 6

The excess fat accumulates in the fat cells in the bodies, adipose tissue to be stored

Then when energy supplies run low, the stored fat is used for energy

Change in energy stores = energy in- energy out

I.e. changing in energy stores equals food energy taken in minus energy spent on metabolism and muscle activities

Energy in is measured in calories taken in each day in the form of food and beverages, which can be easily calculated online , finding energy out is harder

Question 7

What is adipose tissue?

Answer 7

The body’s fat tissue which synthesizes and secretes the hormone leptin involved in appetite regulation

Question 8

How is the energy equation balanced?

How does the equation shows weight gain and loss

So what is the main way to do healthy weight loss?

Answer 8

The energy expended has to equal the energy taken in from carbs, lipids, proteins, and alcohol

If energy input is greater than output, result is weight gain

If energy output is greater than energy input result is weight loss

Increase activity and decrease food intake

Question 9

For each ___ number of calories, you eat an access you store, ___ pounds of body fat

Answer 9

3500calories

Gain 1/2 a kg (1pound)

Question 10

What are the EER?

Answer 10

Estimated energy requirements

The DRI recommendation for energy intake, which accounts for age, gender, weight, and height, and physical activity

But if people deviate from the reference man and women that they use to make these requirements, they need to use a different method to determine their energy requirements

Question 11

What is basal metabolism?

Voluntary activities

Thermic effect of food (TEF)

Basal metabolic rate (BMR)

Answer 11

is basal metabolism:
- the sum total of all the involuntary activities that are necessary to sustain life, including circulation, respiration temperature maintenance, hormone, secretion, nerve activity, and new tissue synthesis, but excluding digestion and voluntary activities.
- basal metabolism is the largest component of the average person’s daily energy expenditure

Voluntary activities:
- intentional activities like walking, sitting or running conducted by voluntary muscles
- most hard to measure and causes errors in finding energy requirements because there are many activities that can expend energy and the intensity/speed of activity varies across ppl
- also body weight play a role: heavy ppl use more energy than lighter ppl when doing the same activity

Thermic effect of food (TEF):
- the body speeds up metabolism in response to having eaten a meal, also called diet induced thermogenesis
- energy required to digest absorb transport metabolize and store nutrients from food
- the result of energy expended due to this is a rise in body temp after eating
- energy expended in this depends on the carb, fat , and protien components in the food and the rate that they’re metabolized

Basal metabolic rate (BMR):
- the rate at which the body uses energy to support its basal metabolism

Question 12

What are the 3 major ways that the body spends energy? “Energy out”

In order of most expenditure to lowest

Answer 12

To fuel, basal metabolism

To fuel its voluntary activities

To fuel the thermic affect of food

Question 13

What percent of a meals energy value does the thermic effect of food take to do?

Answer 13

Uses up to 5 to 10% of a meals, energy value and stepped up metabolism in the five or so hours after the meal

Question 14

What controls basal metabolism

When is BMR lowest

Answer 14

The hormone thyroxine

Less thyroxine secreted, the lower the energy requirements for basal metabolism

BMR is lowest during sleep

Question 15

How do you increase your BMR?

Answer 15

By increasing your voluntary activities

This increases your calorie expenditure each day, so your BMR also increases

Question 16

What factors affect the BMR?

Answer 16

Age : higher in youth, lean body mass decrease with age so older has less BMR

height: taller ppl have larger surface area so higher BMR

Growth:child and prego women have higher BMR

Body composition : more lean tissue, higher BMR, male have more lean tissue so higher BMR

Fever : raise

Stress : raise

Environmental temp: adjusting to temp raise’s BMR

Fasting/starvation: lowers

Malnutrition : lowers BMR

Thyroxine: more thyroxine made, higher BMR

Question 17

What are ways to measure energy expenditure

Answer 17

Measuring energy intake when weight is stable (this means energy in = energy out)

Direct calorimetry :
- measuring energy as heat
- A special design chamber, can determine the total amount of heat released by the body, which is then measured in kilocalories

Indirect calorimetry:
- measuring oxygen consumption and CO2 production
- Needs a portable respiration apparatus that is less expensive simpler and more mobile than directly calirmetry
- indirect calorimetry allows measurements of a wider range of physical activities then direct which is why it’s the preferred method of measurement

Question 18

Why is excerize emphasis in maintaining BMR for weight control?

Answer 18

The more lean body tissue, the higher, the BMR

The more exercise, the more lean body tissue and higher BMR

Question 19

In the thermic affect of food How much energy is used to:

store dietary fat

Store dietary carb

Storing the carb as glycogen

How much total energy intake is needed to process food

Answer 19

dietary fat :
- 3% of the ingested energy is needed to store dietary fat in adipose tissue

Store dietary carb:
- storing dietary carb as body fat requires 23% of energy intake

Storing the carb as glycogen:
- 7%

How much total energy intake is needed to process food:
- 10%

Question 20

What are the most accurate ways of determining energy requirements?

What’s another fairly accurate way?

Another way

Answer 20

Most accurate ways are direct and indirect calorimetry which measure actual energy expenditure

Another way is estimating average energy intake from food when the body weight and activity are stable

Another way is by using the formula for estimate estimated energy requirement (EER)

Question 21

What factors are considered when the DRI estimates energy requirements?

Answer 21

Gender: women have less lean body mass than men and women’s men menstrual hormones raise the BMR just before menstruation

Age : the BMR declines by an average of 5% per decade so age is a determining factor when calculating EER

Physical activity: the DRI committee clusters activities, according to the typical intensity of a days efforts to estimate the energy spent on physical activity

Body size and weight : taller and heavier people have higher BMR so height and weight have to be factored in expiating person‘s EER

Question 22

How to quickly and easily estimate energy need for men and women

Pound to kg

Answer 22

men: kilograms body weight x 24 = Cal/day

Women kilograms body weight x 22 = Cal/day

To convert pounds into kilograms divide pounds by 2.2

Question 23

Do we need to know how to calc EER

Answer 23

Pg 379 idk

Question 24

What are the four most common ways of assessing body weight and body composition

Answer 24

Height and weight charts

BMI

Skinfold measurement

Waist measurement

Question 25

What are height and weight charts in assessing body weight and body composition

Answer 25

The method for determining if overweight and underweight has been to compare personal weights to ideal body weights given in height and weight charts Weaknesses: But the relationship between weight and health can be hard to assess from just height and weight charts One of the main limitations of height and weight charts is they can’t differentiate fat weight from lean muscle weight Other methods give a more accurate assessment of the risk for disease in the western world

Question 26

What is BMI in assessing body weight and body composition What are its strengths and weaknesses What is overweight and obese What bmi does the risk of health problems increase What is the normal BMI range for seniors?

Answer 26

BMI is another anthropometric measure of body weight and composition. It’s based on the relationship of body weight to height It’s an indicator of obesity or underweight, and is calculated by dividing the weight by the square of the person‘s height Weakness: - It’s an indirect measurement, but it has a high relation with body fat - less useful for evaluating non obese ppls body fatness - fails to indicate how much of a person‘s weight is fat and where that fat is located - it’s not suitable for infants, children, adolescence, pregnant, or breast-feeding women or muscular athletes. This is because people with higher muscle mass are heavier than average cause muscle is denser than fat. - best for people between the ages of 20 and 65 Strengths: - It’s a measure of proportional weight in relation to health and allows a wider range of acceptable weights for certain heights than height and weight charts do - good for assessing degrees of obesity Overweight is BMI of 25 to 29.9 and obesity is 30 or greater Risk increase above or below bmi of 18.5-24.9 For senior as normal BMI range begins at 18.5 and extends into the overweight range (25 to 29.9)

Question 27

Formulas for finding BMI Normal body fat percentages for men and women, in the healthy BMI range At what body fat percentage is it bad

Answer 27

Metric: wt(kg)/ ht (m)^2 Imperial : wt(lb)/ ht (in)^2 x (703) Men 12 to 20% Women 20 to 30% Bad: past age 40 is older - Young men more than 22% - older men more than 25% - younger women more than 32% - older women more than 35%

Question 28

What is skinfold (fat fold) measurement in assessing body weight and body composition

Answer 28

Stemgth: - This is a direct measure of body fatness, unlike height and weight tables or BMI The thickness of a fold of skin is measured at different body sites using a caliper then an overall average of fat percent from diff skinfold sites can be used to find the total body fat percent The main two sites that are measured are : - the triceps skinfold (back of the arm midway between the top of the shoulder and elbow) - the subscapular skin fold (on the back parallel to the shoulder blade) Because each side has a different thickness, each measurement has to be compared with the appropriate standard for that body area Weaknesses: - Need to have these measurements taken by a skilled professional because they’re easy to take incorrectly - they may be inconvenient to use in certain healthcare settings - limitation in interpreting body fat percent is the blurry relationship between body fat and the risk of various diseases (don’t know what percent they can be considers obese or underweight or at risk of heart disease)

Question 29

What is waist measurement in assessing body weight and body composition Strength and weaknesses What circumference is higher risk of disease

Answer 29

Using the waist circumference as an indicator of health risks from high body fat levels The waist circumference is measured at the narrowest part of the trunk at the naval The circumference gives an indication of fat stored in the abdominal area which is visceral fat Strengths: - waste circumference is a relatively easy measurement to take and has correlation with chronic disease diseases - Unlike BMI, waste circumference measure can differentiate between a muscular person and a person who carries excess body fat Weakness: - people may not accurately measure their own waist, but this can be overcome with training - with circumference measurements will not accurately reflect risk for pregnant woman Men : - waist circumference greater than 102 cm (40 inches) Women: - waist circumference greater than 88 cm (35 inches) Apple shaped people have higher risks for chronic disease diseases like type two diabetes, heart disease, hypertension, and breast cancer

Question 30

What does risk mean?

Answer 30

Risk is a description used on a weight may be a concern for health Higher risk more likely that health problems may develop, but there are no guarantees

Question 31

What fat is easier to lose through diet and exercise, abdominal fat or hip fat

Answer 31

Abdominal fat

Question 32

What bmi is underweigh What BMI is overweight What BMI is obese

Answer 32

Below 18.5 Between 25 to 29.9 30 or higher

Question 33

What is underweight What happens if underweight ?

Answer 33

Too little body fat for health It’s as serious as a medical problem as overweight, especially in young girls Underweight woman get amenorrhea (cessation of menstruation) and can become infertile: - Women who do give birth with amenorrhea produce unhealthy infant Underweight people have a history of low intake so they may suffer from malnutrition : - this can reduce resistance to infectious disease Underweight people also suffer from physical weakness and reduced resistance to cold temperatures Cancer affects them more because people with cancer often die from starvation and not the cancer itself. So if already underweight it’s bad

Question 34

What are the lifetime prevalence estimates in men and women for : anorexia Bulimia Binge eating What percent of women between what ages have some kind of eating diesorder

Answer 34

anorexia: had occurred in - 0.9% women - 0.3% men Bulimia: - 1.5% woman’s - 0.5% men Binge eating: - 3.5% woman - 2.0% men 5% of women between 14 and 24 years have some kind of eating disorder

Question 35

What are the causes of underweight?

Answer 35

Eating food of insufficient quality or quantity Poor absorption and utilization of food consumed Wasting disease diseases like tuberculosis, AIDS cancer that increase basal metabolic rate Excessive physical activity like athletes and intensive training Psychological or emotional disorders

Question 36

What is obesity defined as?

Answer 36

Over fatness with adverse health effects as determined by reliable measures and interpreted with good medical judgement

Question 37

What is overweight defined as?

Answer 37

Over fatness of a moderate degree

Question 38

What is wasting such as wasting diseases?

Answer 38

The progressive relentless loss of the bodies, tissues, that accompanies certain disease diseases, and shorten survival time

Question 39

What are the risks of being overweight? Do all obese people get ill and what determines this

Answer 39

Obesity is considered a chronic disease Obese people suffer from hypertension, diabetes, heart disease, more than lean people Obesity also causes higher levels of atherogenic adipokines which are protein hormones, made, and released by adipose tissue (fat) cells Some obese people stay healthy and live long. This is because genetic inheritance, abstinence from smoking , and cardiovascular fitness can determine who stays well that is obese 

Question 40

What is central obesity? What is visceral fat? What is metabolic syndrome

Answer 40

Excess fat in the abdomen and around the trunk, this is the most risky obesity Visceral fat is fat stored within the abdominal cavity associated with the internal abdominal organs also called intra-abdominal fat Metabolic syndrome is a combination of central obesity, diabetes or pre-diabetes, high blood glucose, (so insulin resistance), high blood pressure and altered blood lipids that greatly increased the risk of heart disease

Question 41

What is subcutaneous fat? Why is visceral fat so bad

Answer 41

Fat store directly under the skin Visceral fat is readily released into the bloodstream and makes significant contributions to the LDL and increase heart disease risk Sub, tenacious, fat of the abdomen thighs, hips and legs also release fat slowly and contribute less to blood lipids

Question 42

What is adipose tissue

Answer 42

The body’s fat tissue, synthesizes and secretes the hormone leptin involved in appetite regulation

Question 43

What is anabolic metabolism and catabolic metabolism?

Answer 43

After fhe three energy yielding nutrients (carbs, proteins, and lipids) have been digested and absorbed, they are metabolized Anabolism: the nutrients are used to build body compounds Catabolism : - the nutrients are broken down to produce energy, CO2 and water - during catabolism, the chemical bonds of the nutrients are broken, and most of the associated energy is transferred to the chemical bonds of ATP (adenosine triphosphate)

Question 44

What is the metabolism of nutrients regulated by?

Answer 44

Coenzymes: many of which are B vitamins Cofactors : many of which are trace minerals Hormones Even though the vitamins and minerals involved in this process, don’t yield energy they’re essential to liberate the energy from the ones that actually have energy

Question 45

What major fuels are used for muscles to do their activity? What is Gluconeogenesis

Answer 45

The type of fuel used depends on the activity of the muscles Fat is the primary fuel used during rest and prolonged activity Glucose is a major fuel used during short burst of activity and is the source of fuel for the brain and nervous system Gluconeogensis: When there is not enough energy or carb in the diet, like during fasting or starvation, the body creates glucose from protein in the diet or from muscle

Question 46

Is fat easily converted to glucose?

Answer 46

No Only the glycerol component of triglycerides (5% of the molecule) can be converted to glucose

Question 47

What can all three energy nutrients, carbs, lipids, and proteins be converted to if they are in excess

Answer 47

Body fat

Question 48

What is feasting? What all can happen after this

Answer 48

When a person overeats: Excess carbohydrates are stored as glycogen in the liver and muscles But the body only has a limited capacity to store glycogen like this so once glycogen stores are filled, the excess glucose is converted to fat The surplus lipids and proteins are also converted to body fat for storage Alcohol can contribute energy or body fat and is metabolized by the liver to generate energy

Question 49

What is fasting and how is it different from starving What are the effects

Answer 49

Fasting: when a person chooses not to eat and draws on their own energy stores Starving: if they have no choice (are in a famine) they are starving But there is no metabolic difference between the two situations Effects: Less than a day I to the fast, the livers glycogen is used up, now it looks for glucose from other sources Cannibalism of body proteins from the muscles and lean tissue begins when the glycogen stores are depleted and no more carbohydrates are available. This happens many hours after fasting or low carb dieting. Then the skeletal muscles, blood proteins, liver digestive tract lining heart, muscle and lung tissue are burned as fuel. Thus within 10 days of starvation, the person would die To prevent death and respond to farting or carb deprivation, the body converts fat into compounds that the nervous system can use. this is called ketosis

Question 50

What are ketone bodies and they’re arisal and effects

Answer 50

Ketone bodies are acidic compounds, derived from fat, uncertain amino acids. They’re normally rare in the blood and help feed the brain during times when too little carbohydrate is available. Their normal metabolites of the body and at low levels of production they are metabolized The production of ketone bodies increases with fat catabolism during fasting or low carb dieting This is because the lack of carbohydrate makes fatty asses breakdown faster than the body can handle then heat tone bodies are formed, some of which can be used to fuel brain cells and the nervous system system When ketone bodies reach a high concentration in blood and urine ketosis occurs Ketosis also happens when there’s untreated diabetes mellitus( when the body cells are starved of glucose)

Question 51

What is example of a ketone body What is mild and severe Ketosis and results

Answer 51

An example of a ketone body is acetone, which is excreted through the lungs and gives a sweet odour called acetone breath (smells like nail polish remover) Mild ketosis causes appetite, depression, increase in urine output and sometimes nausea Severe ketosis causes acidosis (a decline in the pH of the blood) and a loss of water from body tissues (because water is needed for ketone excretion) Sodium and potassium are also depleted as a consequence blood pressure drops and death occurs as a result from the collapse of the circulatory system

Question 52

Flash card 43 onward have to add stuff from text page 390-393

Question 53

Does a change in the body’s weight indicated a change in body fat

Answer 53

No It can mean shift sin body fluid content , bone minerals, leans tissues like muscle, or contents of the bladder and digestive tract

Question 54

How do you lose fluid weight How do you gain water weight

Answer 54

Take a diuretic (water pill) which make the kidneys take extra water from the blood into the urine Do intense excersizd in heavy clothing to lose fluid as sweat Gained by overcomsuming salt and water

Question 55

What does ketosis do during starving

Answer 55

Reduces the nervous ystems need for glucose by: Instead of breaking down fat molecules all the way to CO2 and water the body takes partially broken down fat fragments and combines them to make ketone bodies It’s also converts some amino acid that can’t be used to make glucose into ketone bodies The ketones bodies flow through the bloodstream and feed the brain. After 10 days of fasting the the brain and nervous system used ketone bodies to meet most of their needs s

Question 56

Describe early food deprivation and later food deprivation

Answer 56

Early: - at this point the nervous system can only use glucose for fuel - the nervous system can’t use fat as fuel, because the body has no enzyme to convert fat to glucose - cant use the muscle glycogen because that reserved only for the muscles - the body protien can be converted to gluocse Later food deprivation: - ketone bodies which are normally at low levels in the blood feed the nervous system and spare muscle and lean tissue protein - this help them live longer (6-8 weeks)

Question 57

In what ways does fasting harms the body

Answer 57

When ketosis upset the acid base balance of the blood of promotes excess mineral loss in the urine , the intestinal lining starts to lose its integrity Also leads to a tendency to overeat or binge when food is available

Question 58

Is fasting a good way to lose weight

Answer 58

No Eat I calories deficit, this give faster rate of weight loss, faster rate of fat loss, and the retention of more lean tissue then a severely restricted fast

Question 59

Summary of feasting

Answer 59

Carb fat and protien turn to glucose fatty acids and amino acids, respectively Glucose is used in body fat storage and love and muscle glycogen storage Fatty acids are used as body fat storage Amino acids are first use to replace body protiens then used at body fat stores and nitrogen loss in the urine

Question 60

Summary of fasting What is the fast continues beyond glycogen depletion

Answer 60

Liver and muscle glycogen stores, body fat stores are converted to glucose and fatty acid’s respectively Then glucose and fatty acids are used as energy Continues: - body protien and body fat are turn into amino acids and fatty acids respectively - amino acids are converted to glucose , nitrogen and some ketone body’s lost I. The urine, and ketone bodies. The glucose and ketone bodies are all used for energy - fatty acids are directly used as energy or turn into ketone bodies which can then be used as energy

Question 61

What is the DRI minimum intake for carbs A healthy amount Are low carb diets good

Answer 61

130g/day Healthy amount: 45-65% of total calories from carbs No they have the same effect as fasting