Chapter Review

BRING IT HOME

CHAPTER 15 BRING IT HOME

Review of popular weight-loss diets

Nutrition surveys demonstrate that more than half of American adults are concerned about their weight and are actively trying to lose unwanted pounds. Many turn to popular “diet” books and programs for guidance and support. Evaluating the safety and effectiveness of these books or programs can be a challenge for both consumers and health professionals. However, by examining the claims, components, and credibility of these popular approaches, you can help determine if a book or program is a sound and safe approach to healthy weight loss and main-tenance. Using book reviews written by registered dietitians at the website for the Academy of Nutrition and Dietetics, we address the following questions to explore considerations for evaluating popular weight loss diets or programs.

Visit the website for the Academy of Nutrition and Dietetics Consumer Diet and Lifestyle Book Reviews at www.eatright.org/dietreviews. Scroll through the Latest Reviews or the extensive alphabetical listing of diet- and health-related books by title to choose two diet books. Click on the link for each diet book and read the review, taking note of factors that the reviewer considers in evaluating the author’s claims, nutritional aspects and other components of the plan that influence compliance, weight loss and maintenance, and overall safety and efficacy of the plan or program.

Name of first book you chose to review:

  1. Briefly describe the book’s claims. After reading the review, do you feel the claims are realistic, grounded in science, and achievable? Explain.

  2. After reading the reviewer’s synopsis of the diet plan, how do you think it differs from other diet plans? What makes it unique or potentially appealing to dieters?

  3. After reading the reviewer’s evaluation of the book’s nutritional pros and cons, are there any specific types or groups of foods that are restricted? What were the reviewer’s primary nutritional concerns about the diet, if any?

  4. After reading the reviewer’s Bottom Line, would you recommend this book or program to an overweight or obese individual? Why or why not?

  5. Do you feel this book’s plan or program is conducive to long-term weight management? Why or why not?

Name of the second book you chose to review:

  1. Briefly describe the book’s claims. After reading the review, do you feel the claims are realistic, grounded in science, and achievable? Explain.

  2. After reading the reviewer’s synopsis of the diet plan, how do you think it differs from other diet plans? What makes it unique or potentially appealing to dieters?

  3. After reading the reviewer’s evaluation of the book’s nutritional pros and cons, are there any specific types or groups of foods that are restricted? What were the reviewer’s primary nutritional concerns about the diet, if any?

  4. After reading the reviewer’s Bottom Line, would you recommend this book or program to an overweight or obese individual? Why or why not?

  5. Do you feel this book’s plan or program is conducive to long-term weight management? Why or why not?

Consider your answers and what you’ve learned from this chapter, and list at least five characteristics of a healthy, safe, and potentially effective weight-loss and weight-loss maintenance program.

This website may also help you to complete this activity: US News and World Reports Best Commercial Diet Plans: http://health.usnews.com/best-diet/best-commercial-diets

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KEY IDEAS

KEY IDEAS

  • Obesity is at epidemic proportions in the United States, with more than two-thirds of adults classified as overweight or obese.

  • Energy, the capacity to do work, is required to perform all functions necessary to sustain life and is obtained through the breakdown of carbohydrates, fats, proteins, and alcohol in food.

  • A calorie, a unit of measure, is defined as the energy required to raise 1 g of water 1°C. The energy in food is commonly measured in units of kilocalories (1,000 calories). A kilocalorie (kcal) is the energy required to raise 1 kg of water 1°C.

  • Energy balance is a reflection of energy intake versus expenditure. Although there are many factors that contribute to the development of obesity, fundamentally it results from chronic positive energy balance. Negative energy balance is necessary for weight loss.

  • Obesity increases the risk of multiple chronic diseases and premature death. Hormonal changes associated with excess body fat cause a low-grade chronic inflammation throughout the body that has adverse health effects.

  • Energy balance and food intake are regulated through a short-term system and a long-term system. The short-term system is mediated by hormones and stomach pressure and is responsible for triggering hunger and satiety during individual meals. The long-term system, mediated by a different set of hormones, adjusts food intake and energy expenditure to maintain adequate fat stores.

  • Satiation is the sense of fullness we feel while eating and leads to the termination of a meal. Satiety is the effect that the meal has on our interest in food and hunger levels after and between meals.

  • The hormone ghrelin stimulates hunger by activating specific neurons in the brain. Ghrelin levels in the blood increase just before meals and decrease after eating.

  • The hormone leptin is produced primarily by adipose (fat) tissue and has a role in long-term energy balance. Its circulating concentration is closely associated with total body fat.

  • Hunger is the biological impulse that drives us to seek out food and consume it to meet our energy needs. Appetite is a desire for or liking of food for reasons other than, or in addition to, hunger.

  • Total energy expenditure (TEE) is composed of basal metabolism, the thermic effect of food, and activity energy expenditure.

  • Basal metabolism is the energy expenditure required to maintain the essential functions that sustain life. It accounts for about 60% of TEE in a typical sedentary individual, with most variation from person to person accounted for by differences in fat-free mass (FFM).

  • Thermic effect of food (TEF) is the energy needed to digest, absorb, and metabolize nutrients in our food. TEF is generally equivalent to 10% of the energy content of the food ingested and does not vary greatly between people.

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  • Activity energy expenditure is the amount of energy individuals expend in physical activity per day and is the most variable component of TEE.

  • Body mass index (BMI) is an indirect measure of body fat calculated from a person’s weight and height. “Underweight,” “normal,” “overweight,” and “obese” are all labels for ranges of body weight on the BMI scale.

  • The greater the BMI, the higher the risk of premature mortality and the risk of obesity-associated diseases. A BMI in the underweight range is also associated with increased premature mortality.

  • Waist circumference indicates body fat distribution and the presence of excess visceral fat, which has been shown to be an independent health risk.

  • Body composition can be measured in a variety of ways, including skinfold thickness with calipers, underwater weighing, air displacement, bioelectrical impedance, and dual-energy x-ray absorptiometry.

  • Weight loss, including dietary modifications and increased physical activity, is recommended for anyone with a BMI of 30 or higher or those who are overweight and have two or more risk factors, or have a large waist circumference. For those with extreme obesity (a BMI of at least 40 or a BMI of at least 35 with additional risk factors), weight loss (bariatric) surgery may be recommended.

  • Modest weight loss and maintenance (5% to 10% of body weight) can improve health, as well as reduce the risk of chronic diseases and premature death.

  • Healthy weight-loss plans maximize nutrient density while reducing calorie intake; increase physical activity; incorporate behavioral strategies to enhance compliance; address individual health concerns; and consider maintenance of a lower body weight.

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NEED TO KNOW

NEED TO KNOW

Review Questions

Question 15.15

1. A calorie is defined as:

  1. the energy required to raise 1 mg of water 1°C.

  2. the energy required to raise 1 g of water 1°C.

  3. a molecule that provides energy to cells.

  4. a byproduct of carbohydrate and fat metabolism.

1. b

Question 15.16

2. Current evidence suggests that a primary cause of adverse health effects related to obesity is:

  1. excess body fat in the hip and thigh area.

  2. long-term negative energy balance.

  3. low-grade chronic inflammation throughout the body.

  4. changes in the acid-base balance of the blood.

2. c

Question 15.17

3. Satiation can be defined as:

  1. the sense or feeling of fullness while eating that leads to termination of the meal.

  2. the effect of a meal on level of hunger and desire to eat after or between meals.

  3. the saturation of adipose tissue with the hormone ghrelin.

  4. an appetite for foods high in fat, particularly saturated fat.

3. a

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Question 15.18

4. All of the following are TRUE with regard to the hormone leptin, EXCEPT:

  1. it is primarily produced by adipose tissue.

  2. its circulating concentration is closely associated with total body fat.

  3. increased levels of leptin in the blood act in the brain to suppress hunger.

  4. it functions primarily in short-term energy balance.

4. d

Question 15.19

5. The primary contributor to an individual’s total energy expenditure is:

  1. basal metabolism.

  2. thermic effect of food.

  3. activity energy expenditure.

  4. meal timing and composition.

5. a

Question 15.20

6. The most variable component of an individual’s total energy expenditure is:

  1. basal metabolism.

  2. thermic effect of food.

  3. activity energy expenditure.

  4. meal timing and composition.

6. c

Question 15.21

7. The thermic effect of food is generally equivalent to ______ of the energy content of food ingested.

  1. 10%

  2. 15%

  3. 20%

  4. 25%

  5. 30%

7. a

Question 15.22

8. All of the following are TRUE with regard to body mass index (BMI), EXCEPT:

  1. that it is a measure of an adult’s weight in relation to his or her height.

  2. that it provides an indirect measure of body fat.

  3. that there is an increased risk of obesity-related diseases and conditions with increasing BMI.

  4. measurement requires the use of skinfold calipers or other body composition assessment tools.

  5. that it may overestimate body fat in athletes and highly trained individuals.

8. d

Question 15.23

9. A BMI of 25 to 29.9 would classify a person as:

  1. underweight.

  2. normal weight.

  3. overweight.

  4. obese.

  5. a candidate for weight-loss surgery.

9. c

Question 15.24

10. Waist circumference can be an indication of “risky” abdominal obesity. A waist circumference of _______ inches for a man would indicate excess abdominal fat and increased health risk.

  1. 27

  2. 32

  3. 37

  4. 42

10. d

Question 15.25

11. All of the following are TRUE with regard to weight loss (bariatric) surgery, EXCEPT:

  1. it dramatically reduces food intake and limits stomach capacity.

  2. it does not have any effect on satiety.

  3. it is reserved for individuals with BMIs of at least 40 or at least 35 with additional risk factors.

  4. it produces significant weight loss in obese patients.

11. b

Dietary Analysis Using SuperTracker

Dietary Analysis Using SuperTracker

Using SuperTracker to Assess Energy Intake

Obesity—having too much body fat—has been linked to a number of health problems, such as heart disease, diabetes, stroke, and many others. The rate of obesity in the United States has continued to increase over the last four decades. Using SuperTracker, you will examine your energy intake and assess your body weight status. You will also identify appropriate diet changes.

Question 15.26

1. Log onto the United States Department of Agriculture (USDA) website at www.supertracker.usda.gov. If you have not done so already, you will need to create a profile to get a personalized diet plan. This profile will allow you to save your information and diet intake for future reference. Do not use the general plan.

Question 15.27

2. Click the Track Food and Activity option. Record three days of food intake.

Question 15.28

3. After you have entered your food for each day, you can then use the “My Reports” feature to analyze your intake. The “Food Groups and Calories” report shows your average intake for each food group. It also shows average calorie intake. The “Nutrients Report” shows an average intake of specific nutrients (such as sodium, calcium, and vitamin D), as well as the foods you consumed that provide the highest or lowest amount of each nutrient. Use the Nutrients Report to answer the following questions.

  1. Did you consume an appropriate number of calories for the three days you selected? If not, were you over or under the target number?

  2. Do you feel that these three days are a typical intake pattern for you? Explain your answer.

  3. According to the body mass index chart, is your body weight within a healthy range? If not, are you overweight or underweight?

  4. Identify three health risks associated with being overweight and obese.

  5. Based on your results, what dietary changes do you believe you should make to be more in line with the SuperTracker recommendations?