Nutrition Exam 4

Calculate body mass index (BMI) 

Weight (kg or lb) / height (m^2 or in^2)  

• kg/m^2 

• lbs/in^2 

Define obesity  

• Signs, symptoms, or tests showing abnormalities in organ function (e.g. reduced range of motion, musculoskeletal system: pain with stiffness, etc) 

• Limitation to activities of daily living 

List cutpoints associated with BMI  

• Underweight: <18.5 

• Normal weight: 18.5 - 24.9  

• Overweight: 25 – 29.9 

• Obese: >30 

List cutpoints for waist circumference as a measure of central obesity 

• Men: >102 cm or >42 in 

• Women: >88 cm or >35 in 

Describe etiological factors for obesity 

• Environmental cues (exposure to food, mental stress, portion sizes) 

• Physiology (hormone resistance to insulin or leptin) 

• Genetic heredity (inborn errors) 

• Governmental, economic, societal forces (lack of culturally appropriate nutrition education in schools)  

• Lifestyle choices (little sleep, little exercise, poor food choices) 

• Physical (built) environment (pedestrian unfriendly neighborhoods, lack of parks) 

• Group or social influences (peer pressure, holiday feasting) 

List components of energy intake and energy expenditure 

• Energy in: based on sex, age, physical activity, height, and weight 

  • Controls: hunger (ghrelin – a hormone that stimulates hunger) and satiety (leptin – a hormone that regulates satiety) 

• Energy out 

  • 50-65% basal metabolic rate (resting energy needed for basic body function) 

  • 25-50% physical activity 

  • 5-10% thermic effect of food 

List and describe lifestyle strategies for weight loss 

• Eating 

  • Eat balanced meals regularly

  • Adequate fiber and protein 

  • Consume consistent meals with a macronutrient balance in meals

  • Choose nutrient-dense food 

  • Choose whole foods 

• Exercise 

  • Increase energy expenditure 

  • Also helps maintain muscle mass if someone is in a calorie deficit for weight loss 

  • Benefits that are not weight-related 

• Other factors 

  • Stress, sleep, and social support  

BMI is only a

screening tool

Obesity =

excess fat mass (body fat or adipose tissue)

Confirm adiposity with:

• waist circumference

• waist to hip ratio

• waist to height ratio

• direct measure (body composition)

BMI should not be used for…

pregnant women and athletes

BMI calculations

weight (kg) / height (m²) OR weight (lb) / height (in²)

Limitations of BMI calculations

not direct measure of body composition and fails to show location of excess fat

BMI underweight classification

<18.5

BMI normal weight classification

18.5 - 24.9

BMI overweight classification

25 - 29.9

BMI obese classification

>30

Preclinical obesity

no abnormal organ function, intervention: health counseling and monitoring

Clinical obesity

signs, symptoms or tests showing abnormalities in organ function (e.g., raised arterial blood pressure, cluster of hyperglycemia + abnormal lipids, musculoskeletal system: pain with stiffness, reduced range of motion)

OR

limitation to activities of daily living

Men waist circumference cut off

>102 cm (40 in)

Women waist circumference cut off

>88 cm (35 in)

Risk from central obesity

visceral fat — deep within the tissue

subcutaneous fat — right underneath the skin

adipokines

• regulate inflammatory processes and energy metabolism in tissues

• Central obesity causes a shift in the balance of adipokines

  • increased inflammation and insulin resistance result

Etiological factors

• environmental cues

• physiology

• genetic heredity

• lifestyle choices

• physical (built) environment

• group or social influences

• government, economic, societal forces

Energy in

Predictive equations

including: estimated energy requirements (DRI) — based on sex, age, physical activity, height and weight

Energy in control

hunger (ghrelin) and satiety (leptin)

Energy out

Estimated energy expenditure

• 50-65% basal metabolic rate

• 5-10% thermic effect of food

• 25-50% physical activity

Factors that affect metabolic rate

age, height, growth, body composition, fever, stress, fasting/starvation/malnutrition, thyroxine

Achieving weight maintenance factors

• Eating: eat regularly, adequate fiber and protein, consume consistent meals with macronutrient balance in meals, choose nutrient-dense foods, choose whole foods

• Exercise: increases energy expenditure, helps maintain muscle mass if someone is in a calorie deficit for weight loss, + benefits that are not weight-related

• Other lifestyle factors: sleep, stress, social support

Physical activity benefits

improves overall fitness: ↑ cardiovascular function, ↑ dyslipidemia, ↑ HDL-cholesterol levels, ↓ blood pressure, ↓ mortality rate

changes occur regardless of weight loss

Benefits of weight loss

↓ cardiovascular risk, ↓ glucose and insulin levels, ↓ blood pressure, ↓ LDL and triglycerides, ↑ HDL, ↓ severity of sleep apnea, ↓ symptoms of degenerative joint disease

Describe locations/types of adipose tissue and what increases risk for chronic disease

waist/abdominal; production of adokines —> insulin resistence

What does BMI not tell us?

the difference between fat mass and lean mass or location of adipose tissue

If BMI is high, what should be considered next?

more extensive measuring

What is HDL cholesterol

Delivers cholesterol from bloodstream to liver; good

physical activity ↑ HDL

What is LDL cholesterol?

Transports cholesterol from the liver to the cell; bad

fiber ↓ LDL, fat

What are major differences between saturated fat, monounsaturated, and polyunsaturated fatty acids?

saturated fat is solid at room temperature (↑ CVD risk and ↑ LDL)

mono/polyunsaturated is liquid at room temperature, (↑ heart health, ↓ LDL cholesterol)

Name some food sources of saturated fat

butter, red meat, coconut oil

Name some sources of polyunsaturated fat

salmon, walnut, sunflower oil (omega-3/6)

Name some food sources for monounsaturated fat

olive oil, avocado, almonds

Modifiable risk factors for heart disease

smoking and alcohol use, physical inactivity, diet

Non-modifiable risk factors for heart disease

family history, advancing age, sex

Healthy blood lipid guidelines — cholesterol

<200 mg/dL

Healthy blood lipid guidelines — LDL

<100 mg/dL

Healthy blood lipid guidelines — HDL

≥60 mg/dL

Healthy blood lipid guidelines — triglycerides

<150 mg/dL

Near optimal blood lipid guidelines — LDL

100-129 mg/dL

Borderline blood lipid guidelines — cholesterol

200-239 mg/dL

Borderline blood lipid guidelines — LDL

130-159 mg/dL

Borderline blood lipid guidelines — HDL

40-59 mg/dL

Borderline blood lipid guidelines — triglycerides

150-199 mg/dL

Unhealthy blood lipid guidelines — cholesterol

≥240 mg/dL

Unhealthy blood lipid guidelines — LDL

>160 mg/dL

>190 mg/dL very high risk

Unhealthy blood lipid guidelines — HDL

<40 mg/dL

Unhealthy blood lipid guidelines — triglycerides

200-499 mg/dL

Total cholesterol HDL ratio

desirable: no higher than 3:1

increased risk: 5:1 or higher

Atherosclerosis

plaque build up in arteries —> inflammation and/or dyslipidemia

injury, inflammation, damage to the artery wall

• environment includes:

  • increase free radicals

  • immune system responds

  • LDL oxidizes —> plaque formation

• can be caused by:

  • smoking/alcohol

  • increased BP

  • increased cholesterol and triglycerides

  • diabetes/insulin resistance

  • obestiy/adipokines

Diet can impact

lipid levels, blood pressure, oxidative stress

these factors are related to development of cardiovascular disease (CVD)

CVD involves the process of inflammation

Hypertension

silent killer (individuals can be asymptomatic)

Hypertension Guidelines 2017 — Normal blood pressure

<120 mmHg and <80 mmHg

Hypertension Guidelines 2017 — Elevated blood pressure

120-129 mmHg and <80 mmHg

Hypertension Guidelines 2017 — High blood pressure Stage 1

130-139 mmHg or 80-89 mmHg

Hypertension Guidelines 2017 — High blood pressure Stage 2

≥140 mmHg or ≥90 mmHg

Hypertension risk factors

smoking, central obesity, sedentary lifestyle, genetics, age, diet (increase in sodium, increase in saturated fats, processed foods)

How much does changing the diet change the LDL cholesterol — Saturated fat

modification: <7% of calories; possible LDL reduction: 8-10%

How much does changing the diet change the LDL cholesterol — Weight reduction (if overweight)

modification: lose 10 lb; possible LDL reduction: 5-8%

How much does changing the diet change the LDL cholesterol — soluble, viscous fiber

modification: 5-10 g/day; possible LDL reduction: 3-5%

Mike's Total Energy Intake is 2235 kilocalories (kcal). If he follows the Dietary Guidelines, what is the highest amount of saturated fat he should consume each day?

(kg x 10% saturated fat)/(9kcal/g)

(2235 kg x 0.10) / (9 kcal/g) = 24.8 g saturated fat

Despite Mike's best efforts his LDL cholesterol is 150 mg/dL. He must now further reduce his saturated fat intake. He should consume less than _ grams of saturated fat per day

Mike's Total Energy Intake is 2235 kilocalories (kcal).

(kg x 7% saturated fat) / (9kcal/g)

(2235 kg x 0.07) / (9kcal/g) = <17 g saturated fat

Hypertension intervention

regular physical activity, weight loss if necessary, limited alcohol intake, stop smoking, DASH eating plan (includes adequate intake of calcium, potassium, and magnesium)

DASH eating plan

rich in low fat dairy products

• 2-3 servings/day (2-3 cups)

high in fruits and vegetables

• 8-10 servings/day (4-5 cups)

low in saturated fat

• use vegetarian protein sources 4-5 times/week

low in sweets

DASH low sodium study

same as DASH but looked at 3 groups, each group a different level of sodium restriction

1500 mg sodium was more effective at lowering blood pressure

• more difficult to follow

lowers hypertension

Metabolic syndrome

any 3 of the following:

central obesity, high triglycerides, hypertension, prediabetes or diabetes, low HDL (<40 mg/dL for men, <50 mg/dL for women)

increases risk for CVD and stroke

Type 2 diabetes — risk factors

obesity, family history, sedentary lifestyle

Type 2 diabetes — symptoms

increase blood glucose, increase urination/thirst, increased fatigue

Type 2 diabetes — complications

death, blood vessel effects, peripheral problems (sights, temperature, touch), blindness, kidney failture, overall affects vascular system

Diabetes — diagnosis

fasting plasma glucose

Fasting plasma glucose

≥ 126 mg/dL or A1C ≥ 6.5%

Diabetes — classification: type 1

produce little or no insulin (autoimmune disease)

Diabetes — classification: type 2

high insulin levels, insulin resistance

Diabetes — classification: pre diabetes

higher than normal fasting blood sugar but not high enough to diagnose diabetes (100-125)

Diabetes — classification: gestational diabetes

diabetes during pregnancy

Prevention — diabetes prevention program

compared intensive lifestyle program with medication

Prevention — intensive lifestyle program

7% weight loss, 150 min physical activity per week, 58% reduction in development

Prevention — medication group

metformin, 31% reduction in risk

Diabetes treatment

diet: increase fiber, lean/plant protein, reduce saturated fats, reduce sugar intake, balance carbohydrates

exercise

self monitoring: finger prick onto strip

medications