human nutrition chapters 8-14

Question 1

what happens in the GI tract when a person eats?

Answer 1

• the GI muscles contractions increase , cells producing digestive juices activate

Question 2

what is the thermic effect of food? what are its alt names?

Answer 2

• the energy req to process food, including digestion, absorption, transportation, metabolism and nutrient storage
• specific dynamic effect (SDE) or ( SDA ) specific dynamic activity

Question 3

what is the sum of the thermic effect of food and any increase in metabolic rate due to overeating called

Answer 3

sum of the thermic effect of food and any increase in metabolic rate due to overeating is known as diet-induced thermogenesis (DIT).

Question 4

What percentage of energy intake is usually estimated as the thermic effect of food? Provide an example.

Answer 4

The thermic effect of food is estimated at 10 percent of energy intake. For instance, a person ingesting 2000 kcalories would likely expend around 200 kcalories on the thermic effect of food.

Question 5

How do the proportions of thermic effect vary for different foods?

Answer 5

is generally greater for high-protein foods compared to high-fat foods. Additionally, it is influenced by factors such as meal size and frequency.

Question 6

Why is the thermic effect of food often ignored when estimating energy expenditure for most purposes?

Answer 6

The thermic effect of food is usually ignored because its contribution to total energy output is smaller than the probable errors involved in estimating overall energy intake and output.

Question 7

Define “adaptive thermogenesis” and provide examples of circumstances that trigger it.

Answer 7

is the adjustments in energy expenditure related to changes in the enviorment like colder environments or physiological events

-ex: physical conditioning , overfeeding , starvation , trauma and other types of stress

Question 8

Why is adaptive thermogenesis not included when estimating energy requirements for most healthy people?

Answer 8

it is highly variable and specific to individuals, making it challenging to accurately estimate its contribution to overall energy expenditure for most healthy people.

Question 9

What are some challenges associated with determining the ideal body weight?

Answer 9

questions about ideal body weight can be complex and vary depending on different perspectives.

Question 10

How does society, particularly the media, influence perceptions of ideal body weight?

Answer 10

through magazines, movies, and television, often promotes unrealistic ideals for body weight, especially for women. The media’s portrayal suggests that being thin is equated with beauty and happiness, influencing people’s weight concerns and dieting patterns.

Question 11

Why is perceived body image mentioned as being unrelated to actual body weight or size?

Answer 11

Perceived body image may not align with actual body weight or size, leading individuals of various shapes, sizes, and ages to be dissatisfied with their bodies. This dissatisfaction can result in harmful behaviors such as extreme dieting, diet pill abuse, and avoidance of healthcare.

Question 12

What is the primary criterion for determining ideal body weight according to the passage?

Answer 12

The most important criterion is good health and longevity. The passage emphasizes that people should weigh enough and have sufficient body fat to meet basic needs without incurring health risks.

Question 13

What is the Body Mass Index (BMI), and how is it calculated?

Answer 13

The BMI is a measure of a person’s weight relative to height, calculated by dividing the weight (in kilograms) by the square of the height (in meters).

Question 14

hat BMI range is considered healthy?

Answer 14

The healthy weight range falls between a BMI of 18.5 and 24.9.

Question 15

hat health risks are associated with too much body fat, according to the passage?

Answer 15

Excessive body fat is a major risk factor for life-threatening diseases, including heart disease, type 2 diabetes, and some cancers.

Question 16

escribe the BMI classifications presented

Answer 16

The classifications are underweight (BMI less than 18.5), healthy weight (BMI 18.5 to 24.9), overweight (BMI 25 to 29.9), and obese (BMI 30 or more).

Question 17

why might BMI not be an accurate reflection of body composition?

Answer 17

BMI reflects height and weight measures but not body composition. Muscular athletes, for example, may be classified as overweight by BMI standards despite having low body fat.

Question 18

What considerations are mentioned regarding the appropriateness of BMI standards for different populations?

Answer 18

BMI guidelines may be inappropriate for some populations due to differences in body composition among people of different ages, ethnicities, and racial groups. For instance, the passage notes that blacks may have greater bone density and protein content than whites, potentially leading to an overestimation of overweight and obesity prevalence using BMI standards.

Question 19

What limitations do weight measures have in assessing disease risk, according to the passage?

Answer 19

Weight measures fail to reveal how much of the weight is fat and where the fat is located.

Question 20

hat factors determine the ideal amount of body fat for athletes? Provide the recommended percentage range for young men and young women athletes.

Answer 20

The ideal amount of body fat for athletes depends on providing fuel, insulation, protection, nerve impulse transmission, and hormone support. For young men, the recommended percentage is 7 to 16 percent, and for young women, it is 15 to 22 percen

Question 21

ow does body fat distribution impact health, and what health risks are associated with central obesity independently of BMI?

Answer 21

Excessive visceral fat stored around abdominal organs contributes significantly to heart disease, cancers, diabetes, and related deaths independently of BMI.

Question 22

Explain the differences in body fat distribution between men and women.

Answer 22

Men typically have more visceral fat, especially past menopause, while women, during their reproductive years, commonly have lower body fat around the hips and thighs.

Question 23

What is waist circumference, and how is it related to central obesity? Provide the recommended measurements for women and men indicating a high risk of central obesity-related health problems.

Answer 23

Waist circumference is an anthropometric measurement used to assess abdominal fat. Women with a waist circumference greater than 35 inches and men with a waist circumference greater than 40 inches have a high risk of central obesity–related health problems.

Question 24

Explain the significance of the waist-to-height ratio in assessing disease risks.

Answer 24

Waist circumference should be less than half of a person’s height, and the waist-to-height ratio is a useful measure of disease risks.

Question 25

What are some other methods mentioned in the passage for estimating body fat and its distribution, apart from BMI and waist circumference?

Answer 25

Other methods include total body water, radioactive potassium count, near-infrared spectrophotometry, ultrasound, computed tomography, and magnetic resonance imaging.

Question 26

How does the passage describe the correlation between body weight, body fat, and disease risks?

Answer 26

: Body weight and body fat correlate with disease risks, suggesting a greater likelihood of developing chronic diseases and shortening life expectancy for those with a higher BMI and waist circumference.

Question 27

What is the relationship between BMI and mortality, and what does the J-shaped curve describe?

Answer 27

The J-shaped curve describes the relationship between BMI and mortality, indicating that both underweight and overweight present risks of premature death. Mortality risks are lowest when BMI ranges between about 20 and 30.

Question 28

What independent factors, mentioned in the passage, can influence health risks irrespective of BMI? Provide examples.

Answer 28

Factors such as smoking habits raise health risks, while physical fitness lowers them. The passage provides an example of a man with a BMI of 22 who smokes and a woman with a BMI of 32 who engages in brisk walking.

Question 29

What percentage of US adults are underweight?

Answer 29

Fewer than 2 percent of US adults are underweight.

Question 30

What are some potential causes of being underweight mentioned in the passage?

Answer 30

Underweight may be due to malnutrition, smoking habits, substance abuse, or illnesses.

Question 31

Why is a complete assessment necessary for underweight individuals?

Answer 31

Weight and fat measures alone would not reveal underlying causes, and a complete assessment, including a diet and medical history, physical examination, and laboratory tests, is required.

Question 32

How does underweight affect individuals facing wasting diseases like cancer?

Answer 32

Underweight individuals may struggle to preserve lean tissue during the fight against wasting diseases, increasing mortality risks.

Question 33

: What health risks are associated with underweight women?

Answer 33

Underweight women may experience menstrual irregularities, infertility, and an increased risk of giving birth to unhealthy infants.

Question 34

What is the financial cost of obesity-related illnesses to the nation annually?

Answer 34

Obesity-related illnesses cost the nation $147 billion annually, comparable to or exceeding the medical costs of smoking.

Question 35

What is the relationship between obesity and cardiovascular disease risk?

Answer 35

Obesity is strongly linked to elevated blood cholesterol and hypertension, increasing the risk of heart attack and stroke.

Question 36

What diseases are associated with chronic inflammation in obesity?

Answer 36

Chronic inflammation in obesity contributes to diseases like diabetes, hypertension, and atherosclerosis, forming a cluster known as the metabolic syndrome.

Question 37

How does weight loss affect insulin resistance and inflammation in obese individuals?

Answer 37

Weight loss can effectively reverse atherosclerosis and lower both blood cholesterol and blood pressure in overweight and obese people, improving inflammation and the metabolic syndrome.

Question 38

How does weight gain after the age of 18 influence the risk of developing diabetes?

Answer 38

A weight gain of more than 10 pounds after the age of 18 doubles the risk of developing diabetes, even in adults of average weight.

Question 39

What is the relationship between inflammation and the metabolic syndrome?

Answer 39

Chronic inflammation in obesity contributes to the metabolic syndrome, increasing the risks for diabetes, hypertension, and atherosclerosis

Question 40

How does obesity influence the risk of developing some cancers?

Answer 40

The duration and severity of overweight or obesity increase the risk of developing some cancers, possibly due to elevated levels of hormones or chronic inflammation.

Question 41

What is “healthy obesity,” and how stable is this condition over time?

Answer 41

refers to obese individuals with normal blood pressure, blood glucose, and blood lipids. It appears to be a relatively unstable condition, transitioning to unhealthy over time

Question 42

Does BMI alone provide a complete picture of health risks?

Answer 42

No, BMI and weight gains/losses do not tell the whole story. Physical activity and fitness also play major roles in health and longevity.

Question 43

What percentage of women and men suffer from anorexia nervosa, bulimia nervosa, and binge eating disorder according to large national surveys?

Answer 43

0.9% women, 0.3% men; Bulimia nervosa: 0.5% women, 0.1% men; Binge eating disorder: 3.5% women, 2% men.

Question 44

what are the multiple factors that experts believe contribute to the development of eating disorders

Answer 44

Sociocultural, psychological, and neurochemical factors.

Question 45

What is the current prevalence of overweight and obesity in the United States, and how has it changed over the past five decades?

Answer 45

stimated to be around 70 percent of adults. Over the past five decades, obesity has increased in every state, across genders, and among all age groups, races, and educational levels.

Question 46

How has the prevalence of childhood overweight changed, and where can additional information on this topic be found?

Answer 46

The prevalence of childhood overweight has risen significantly. Additional information on childhood overweight can be found in Chapter 16.

Question 47

What factors contribute to the global spread of obesity, according to the text?

Answer 47

The increasing rates of obesity worldwide are attributed to a global food system that provides energy-dense, processed, affordable, and well-marketed products.

Question 48

Explain how fat cell development occurs, and why childhood and adolescence are critical periods for preventing obesity.

Answer 48

Fat cell development involves an increase in both the number and size of fat cells. Childhood and adolescence are critical for prevention as fat cell numbers increase most rapidly during this period. Researchers are exploring ways to induce fat cell death to decrease the number of fat cells.

Question 49

. What are the consequences of excess fat accumulating outside of adipose tissue, and what is this type of fat called?

Answer 49

Excess fat accumulating outside adipose tissue is called ectopic fat. It disrupts normal metabolism and contributes to the development of diseases such as heart failure and fatty liver.