Exam 6 Study Guide

How is body mass index (BMI) calculated? What information do you need? Write the formula, including the units for weight and height.

BMI=weight in kilograms/(height in meters)²

Write out the adult BMI range for underweight, healthy weight, overweight, and obesity

Underweight is below 18.5; healthy 18.5-24.9; overweight 35.0-29.9; obesity 30.0 or higher

What is normal weight obesity? Describe the person’s BMI, muscularity status (high or low) and body fat, the activity level it is most common with, and the disease it has been linked to. How is it different from a highly muscular person with a high BMI?

A normal BMI with a high percentage of body fat. It is most common in physically inactive people and has been linked to a higher risk of coronary heart disease. High muscle with a high BMI describes a muscular person, not normal weight obesity

List at least five conditions that obesity increases the risk of. Name two conditions that obesity does not cause

Any five: type 2 diabetes, coronary artery disease, stroke, certain cancers, hypertension, metabolic syndrome, asthma, dementia, gout, dyslipidemia, fatty liver disease. Not caused by obesity: type 1 diabetes and celiac disease

Explain how chronically high blood insulin levels and insulin resistance affect a person’s risk of obesity. Does it increase or decrease the risk of obesity?

They increase the risk. Insulin is one of the hormones that regulate the growth and division of fat cells, and high insulin levels promote fat storage

Compare subcutaneous and visceral fat. Which one insulates the body and protects muscles and bones from bumps and bruises? Which one sits deep in the abdomen and protects the digestive organs?

Subcutaneous fat lies under the skin; it insulates the body and protects muscles and bones from bumps and bruises. Visceral fat lies deep in the abdomen and protects the digestive organs

Describe how each method estimates body composition: dual-energy x-ray absorptiometry (DXA), air displacement (BOD POD), bioelectrical impedance analysis (BIA), underwater weighing, and skinfold measurements

DXA: scans the body with two low-energy x-rays. Air displacement: measures body volume inside a large chamber (the BOD POD). BIA: send a weak electrical current through the body, which water and electrolytes conduct. Underwater weighing: compares the density of fat and lean mass with water. Skinfold: calipers measure skinfold thickness at several sites

Define nonexercise activity thermogenesis (NEAT). What are some examples of movements that would increase NEAT?

Basal metabolism: energy for basic body functions at rest. Thermic effect of food: energy to digest, absorb, and process food. Physical activity: energy for voluntary movement and exercise. NEAT: energy for movement that isn’t planned exercise, such as fidgeting, posture, and shivering

Which gland produces the primary hormone that controls metabolic rate, and what is that hormone called?

The thyroid gland, which produces thyroid hormone

Which part of the brain controls hunger and satiety?

The hypothalamus

For each hormone, name where it is made and what it does: ghrelin, peptide YY, amylin, leptin

Ghrelin: stomach; stimulates eating. Peptide YY: intestine; signals the stomach to reduce ghrelin. Amylin: beta cells of the pancreas; slows gastric emptying and signals the hypothalamus to reduce hunger. Leptin: fat cells; reduces hunger and increases energy expenditure

Which hormone in question 11 stimulates hunger? Which one is secreted by the beta cells of the pancreas and slows digestion by delaying gastric emptying?

Ghrelin stimulates hunger. Amylin comes from the pancreatic beta cells and eelays gastric emptying

Explain what ghrelin is and what it does. Which cells produce leptin, and how does it affect hunger. How is satiety different from hunger. What is a “thrifty” metabolism?

Ghrelin is a hormone secreted by the stomach that stimulates eating (it is not an enzyme). Fat cells produce leptin, which reduces hunger. Satiety is the sense that enough food has been eaten; hunger is the feeling that drives a person to eat. A “thrifty” metabolism conserves energy and stores fat readily, so it burns less, not more

What is an obesogenic environment? List four features of one.

External conditions that promote excess weight gain. Features: easy access to highly processed foods, high-calorie foods low in nutrients, reduced physical activity, and high stress

According to the Physical Activity Guidelines for Americans, how many minutes per week of moderate intensity activity should adults get for weight maintenance?

At least 150 minutes of moderate-intensity activity (or 75 minutes of vigorous intensity activity)

According to the DSM-5, what are the three main types of eating disorders? Name two other conditions from this chapter that are not one of the three main types.

Anorexia nervosa, bulimia nervosa, and binge-eating disorder. Not among the three: diabulimia, orthorexia nervosa, muscle dysmorphia, night-eating syndrome, and the female athlete triad

How do people with bulimia nervosa typically avoid gaining weight after a binge?

Purging, including self-induced vomiting

Define each condition: diabulimia, orthorexia nervosa, muscle dysmorphia, and bulimia nervosa.

Diabulimia: a person with type 1 diabetes skips insulin or uses less than prescribed to control weight. Orthorexia nervosa: and extreme obsession with eating foods perceived as “healthy”. Muscle dysmorphia: a preoccupation with the belief that one’s body is too small or not muscular enough. Bulimia nervosa: repeated binges followed by purging or other behaviors to prevent weight gain

What three conditions make up the female athlete triad?

Low energy availability (with or without disordered eating), loss of menstrual periods, and reduced bone mineral density

Genevieve is a 23-year-old ballet dancer who trains about 7 hours a day. She has frequent stress fractures in her feet and has not had a period in 8 months, and she is not pregnant. What condition does she most likely have? Which part of the condition explains her stress fractures?

The female athlete triad. Reduced bone mineral density explains the stress fractures

Describe night-eating syndrome. What do people with it believe about falling asleep? What is their appetite like in the morning? How is it different from sleepwalking?

Eating a large share of daily food in the evening or at night. People believe they can only fall asleep with a full stomach, and they have little appetite in the morning. Unlike sleepwalking, they are awake and aware when they eat

What is the preconception period, and how long is that window of time?

The time before pregnancy, specifically the 3 month window before pregnancy

Define infertility. About what percent of U.S. females ages 15 to 49 experience it? Name two factors that contribute to it.

Failure to conceive after 12 months of trying. About 20%. Contributing factors: hormonal imbalances (such as PCOS or diabetes), genetic factors, and obesity

Explain how diet affects fertility. Which nutrients support healthy egg production, and which substances reduce fertility?

Diet does affect fertility, partly through blood insulin levels. Folate, iron, and vitamin D support healthy egg production, while alcohol and caffeine reduce fertility

What is conception? How is it different from ovulation?

Conception is the point at which a sperm fertilizes the egg and pregnancy begins. Ovulation is when the ovary releases an egg

How long is the prenatal period, how is it divided, and how long does each part last?

From conception to birth. It is divided into three trimesters of about 13 weeks each

Which organ of pregnancy transfers nutrients and oxygen from the mother’s blood to the embryo or fetus? How is it different from the uterus?

The placenta. The uterus is where the baby grows; the placenta forms on the uterine lining

Which maternal tissue contributes the most to normal weight gain during pregnancy, and about how many pounds does it add? How does it compare with maternal blood, retained fluid, and the placenta?

Maternal fat, about 7lb. That is more than maternal blood (about 4lb), retained fluid (about 4lb), or the placenta (about 1.5lb)

Which four nutrients do U.S. public health experts list as nutrients of concern during pregnancy?

Folate, iron, iodine, and choline (vitamin C is not one of them)

Why do pregnant females generally need a supplement that contains folic acid?

Folic acid prevents neural tube defects such as spina bifida. The neural tube forms before week 4, often before a female knows she is pregnant

Which mineral is needed to prevent anemia, extreme fatigue, and low birth weight? What is its RDA during pregnancy?

Iron. RDA: 27mg per day

Sudha is in her second trimester. Which mineral does her body need to make thyroid hormone for normal fetal brain development?

Iodine

What is fetal alcohol syndrome, and what causes it?

Severe birth defects in infants whose mothers drank alcohol excessively during pregnancy. It is the most severe form of fetal alcohol spectrum disorder, and there is no known safe amount of alcohol

What is preeclampsia, and what are its risk factors?

High blood pressure in pregnancy with protein in the urine and swelling. Risk factors: maternal obesity, diabetes, carrying twins or triplets, age under 18 or over 40, and very low calcium or vitamin D intake

Define lactation. Which cells in the breast produce milk?

The production of milk by cells that line the mammary alveoli in breast tissue

Describe the role of each hormone in pregnancy or lactation: prolactin, oxytocin, progesterone, and estrogen

Prolactin stimulates milk production. Oxytocin releases releases the milk (let-down). Progesterone slows the GI tract and helps the uterus and breasts enlarge. Estrogen helps the uterus and breasts enlarge and suppresses ovulation

How many extra kilocalories per day does a breastfeeding mother need above her prepregnancy intake?

300 to 400 kcal per day

Give the age range for each stage: infancy, toddler, preschool-age, school-age, and adolescence

Infancy: birth-12 months. Toddler: 1-3 years. Preschool-age: 3-5 years. School age: 6-11 years. Adolescence: 12-19 years

Describe the rooting, suck, and extrusion reflexes. Which one makes a baby turn its head and open its mouth when its cheek is stroked?

Rooting: turns toward a stroked cheek and opens the mouth. Suck: draws milk and coordinates sucking, swallowing, and breathing. Extrusion: the tongue pushes objects out of the mouth

Name the components of human breast milk that infant formulas do not contain. Which nutrients are found in both breast milk and formula?

Only in breast milk: antibodies, hormones, immune factors, growth factors, and enzymes. In both: vitamins, iron, calcium, fat, carbohydrate (lactose), protein, and water

Which lipid is necessary for the proper development of an infant’s nervous system?

DHA

Which food should caregivers never feed to infants, and why?

Honey, because it may contain clostridium botulinum spores that cause infant botulism

What are complementary foods? Around what age are they usually introduced, and what signs show a baby is ready?

Complementary foods are an infant’s first solid foods, introduced around 6 months. Signs of readiness: sits with some support, holds head steady, has lost the extrusion reflex, opens mouth for food, shows interest in others’ food

Which nutrient is a preschool-age child most likely to get enough of? Which nutrients do preschoolers often fall short on?

Protein. Preschoolers often fall short on fiber, potassium, and vitamin D

Compared with preschoolers, what do school-age children tend to eat more of? What do they eat less of?

More: foods away from home, friend foods, sugary drinks, and sodium. Less: fruits, vegetables, and whole grains

Name one factor that has a negative effect on a school-age child’s diet and two that have a positive effect

Negative: viewing ads for sugar-sweetened soft drinks. Positive: serving fresh fruit with meals and snacks, eating meals at home, limiting chips and soft drinks

What is a major nutrition concern for adolescent females?

Low iron intake

Give the BMI-for-age percentile ranges for underweight, healthy weight, overweight, and obesity in children. Shakena is 7, and her BMI-for-age is at the 86th percentile. How is her weight classified?

Underweight below the 5th percentile; healthy 5th to below 85th; overweight 85th to below 95th; obesity 95th and above

Define senescence. What is the medical specialty that focuses on the health care needs of older adults called? How is it different from pediatrics, obstetrics, and orthopedics?

Senescence: declining organ function and increased vulnerability to disease with age. Geriatrics is the specialty for older adults

Define life expectancy, life span, longevity, and healthy life expectancy. Which one is the average length of time a person born in a specific year can expect to live?

Life expectancy: the average length of time a person born in a specific year can expect to live (this is the answer). Life span: the maximum years a human can live. Longevity: the capability of living a long life. Healthy life expectancy: years lived without disability or serious disease

Evangeline lives in Ikaria, Greece, a region where many people live to 100 or older. What haits contribute to longevity there?

Regular physical activity through daily life, like walking and gardening; a diet rich in plant-based foods; and time with family and friends (avoiding naps and sleeping only 5-6 hours a night is not one of them.)

Describe the damage (error) theory and the programmed theory of aging. Which theory say organs simply wear out with use and abuse?

Damage (error) theory: organs wear out from use and abuse, such as poor diet, smoking, and free radicals. Programmed theory: aging is built in, as certain genes switch on over time. The damage theory is the answer

Describe the normal physiological changes that happen with aging in each of these: hormones (such as estrogen), arteries, lungs, kidneys, the digestive tract (saliva and heartburn), skin, and the immune system

Hormones: less estrogen, growth hormone, and thyroid hormone. Arteries: stiffen and harden. Lungs: reduced capacity. Kidneys: filter blood more slowly. Digestive tract: less saliva and more heartburn. Skin: less elastic and less efficient at making vitamin D. The immune system: more vulnerable to infections and cancer

Margaret is 87. Compared with when she was 27, how has her stomach’s secretion of intrinsic factor changed? How have her energy needs and bone density changed?

Her stomach secretes less intrinsic factor, so she absorbs less vitamin B-12. Her cells need less energy, and her bones are less dense

List at least four factors that contribute to reduced food intake in older adults

Any four: loss of teeth, depression, reduced mobility and flexibility, reduced taste and smell, trouble swallowing, cognitive decline, low income

Which macronutrient is most likely to fall below recommendations in older adults?

Protein

Which two vitamins are often lacking in older adults’ diets? Which one is especially lacking in older adult females?

Vitamin D and vitamin B-12. Vitamin D is especially lacking in older adult females

Explain how the body’s water content and the risk of urinary incontinence change with age. What are three signs of dehydration in older adults?

Body water content decreases, and the risk of urinary incontinence increases. Signs of dehydration: weakness, constipation, and mental confusion

What is polypharmacy, and how can it affect nutrition?

Taking several prescribed medications daily to treat a variety of health conditions. It can change taste, cause GI bleeding or diarrhea, change appetite, and alter blood glucose

What is the difference between sarcopenia and sarcopenic obesity?

Sarcopenia is the loss of skeletal muscle mass and strength. Sarcopenic obesity is muscle loss combined with an increase in body fat