Midterm 2 Review
Chapters 5-8
Midterm #2
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Chapters 5-8
Multiple Choice and True/False (50)
Multi-part Short Answers (4)
Bring: Scantron, Non-graphing calculator,
pencil, eraser
Chapter 5: Carbohydrates
• Carbohydrates include sugars, starches, and
fibers
• Major food sources: plants
• Two main carbohydrate types:
– Simple (sugars): mono + disaccharides
– Complex (starches and fiber)
• Bond: alpha or beta glycosidic bonds
Carbohydrates
• High Fructose Corn Syrup
• Complex Carbohydrates
– Starch vs. Glycogen
– Amylose (straight) vs. Amylopectin (branched)
– Fiber: non-digestible before entering large intestine
• Soluble: dissolves in water  gel-like  slows digestion
– Fermentable
• Insoluble: does not dissolve in water  creates a bulk 
larger, softer stool
– Fermentable (Resistant Starch) vs. Non-Fermentable
Fiber Diagram
Carbohydrates Digestion & Absorption
• Mouth: Salivary amylase
• Small intestine:
– Enzymes: pancreatic amylase, brush border enzymes
– End product: Glucose
– Liver stores and releases glucose to maintain blood
glucose
• Large intestine:
– Bacteria in colon digests rest of carbohydrates, soluble
fiber, and resistant starch (a type of insoluble fiber) to
gas + short chain fatty acids  energy supply for colon
cells
Regulating Blood Glucose Levels
Carbohydrates and Health
• Glycemic Index
• Hyperglycemia vs. Hypoglycemia
– Hyperglycemia consequences: sweet urine,
ketosis/acidosis (if you are also diabetic)
– Hypoglycemia:
• Reactive Hypoglycemia
• Fasting Hypoglycemia
• Consequences: ketosis/acidosis, coma  death
– Diabetes I, II, Gestational Diabetes
Carbohydrates in your diet
• Nutritive vs. Non-nutritive sweeteners
– Nutritive:
• Natural, Refined, Sugar Alcohol
• Can be “sugar free,” but not always calorie free
– Non-Nutritive: “Artificial sugar”
• Saccharin (bladder cancer), Aspartame (PKU),
Acesulfame K (Stable under heat), Sucralose
Chapter 6: Lipids
• Types: Triglycerides, Phospholipids, Sterols
• Made of: Glycerol + Fatty Acids
• Bonds and Saturation:
– Saturated fatty acids vs. Unsaturated fatty acids
(MUFA, PUFA)
• Saturated fatty acids: all single bonds
• Unsaturated fatty acids: Cis (natural) vs. Trans fatty
acids (partial hydrogenation)
• Essential vs. Non-essential fatty acids
Lipids
• Triglycerides
– Functions: energy storage, insulation/protection, etc.
– Visceral vs. Subcutaneous fat
– Food sources by most prevalent type: Saturated
(animal) vs. Polyunsaturated (plants)
• Phospholipids:
– Functions: Emulsifier (bile, lingual lipase), Structural
element for cell membrane (lipoprotein carrier)
• Sterols
– Functions: structural component, precursors to other
substances
Lipid Absorption
Lipoprotein Pathway Summary
Lipid Digestion
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Fat hydrogenation Pros/Cons
Lipids and Health
AHA diet and lifestyle recommendations
Metabolic Syndrome
Cancer
Proteins
• Made up of: Amino acids
– Essential, Non-Essential, Conditionally essential
• Bond: Peptide bond
• Denaturalization of Protein (factors and
consequence)
• Functions of Body Proteins
Summary of Protein Digestion and
Absorption
Function of Blood Amino Acid Pool
Protein in the Diet
• Nitrogen balance
• Recommended protein intake
– Adult RDA = 0.8g/kg of body weight
– Infants have highest needs relative to body weight
• Physical stress increase your body’s needs for
proteins
• Protein Quality: Complete vs. Incomplete
• Vegan vs. Vegetarian, Pros/Cons
Health Effects of Protein
Too Little Protein
• Protein-energy malnutrition
(PEM)
– Kwashiorkor: severe protein
deficiency
– Marasmus: severe calorie
deficiency
Too Much Protein
• Heart Disease
• Obesity
• Osteoporosis
• Cancer
Energy Balance and Weight
Management
• Energy input vs. output
• Food intake is regulated by sensations of
hunger, satiation, satiety, appetite
– Physiological vs. psychological
• Internal (physiological response) vs. External
cues (environment)
– Internal: sense of fullness, NPY, Ghrelin, Leptin
– External: diet composition, sensory properties,
portion size, environment/social, emotion
How does our bodies use
energy?
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Resting energy expenditure or
(REE)
Thermic effect of food (TEF)
Physical activity (PA)
REE + TEF + PA = Total Energy
Expenditure
Measuring Body Weight and Fat
• Body composition
– Is the relative amount of fat and lean muscle mass
• Assess body weight via BMI
• Assess body fat via DEXA/DXA, Underwater
weighing, BodPod, Skinfold measurements,
Bioelectrical impedance
Overweight and Obesity
• US: 2/3 or 66% of American adults are overweight/obese
• Factors in development of obesity
– Biology: genetics, race, fat cell development,
sex/age
– Social environmental factors: socioeconomic
status, built environment, social factors
– Lifestyle and behavior: psychological, physical
activity
• Weight cycling or “yo-yo dieting”
Diet and Eating Habits
• Adopting a healthy behaviors
• Crash diets don’t work
• Balancing energy sources: Carbs (45-65%),
Fats (20-25%), Proteins (10-35% of total
calories)
• Weight management approaches
• Underweight
Resources
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Your required textbook
Lecture Notes
Practice Quiz (online)
Classmates
Professor