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• The exam consists of 40 questions, worth 100 points total, with 3 extra credit opportunities.
• The exam will include multiple-choice, fill-in-the-blank, true/false, and matching questions.
• A lockdown browser is required and must be working before the exam.
• Pay close attention to bold or colored items in PowerPoint presentations.

Lecture 1: Dietitians vs. Nutritionists

• A dietitian has a bachelor's degree from an accredited U.S. university and has completed specific education requirements.
• A nutritionist can be anyone, even with just a 6-month certification.
• It's generally not advisable to give nutrition advice without proper credentials.

Lecture 2: Energy Functions and Metabolic Rates

• Energy has three main functions: providing energy, supplying building blocks for repair, growth, and maintenance, and regulating body processes (metabolism).
• Metabolism refers to the chemical processes converting food and drinks into energy (ATP), while metabolic rate is the speed of these processes.
• Basal Metabolic Rate (BMR): Metabolic rate during sleep or deep rest, essential for basic functions.
• Resting Metabolic Rate:** Minimum metabolic rate to keep you alive and functioning at rest, accounting on average to 50-75% of total calorie expenditure.
• Thermic Effect of Food (TEF): Calories burned during digestion and processing of food, typically 10% of total energy expenditure.
• Thermic Effect of Exercise (TEE): Increase in calories burned during exercise.
• Non-Exercise Activity Thermogenesis (NEAT): Calories for activities other than exercise like fidgeting, changing posture, standing, and walking.
• Factors affecting metabolic rate: exercise, genetics, age, muscle mass, body size, environmental temperature, physical activity, and hormone disorders.
• Scientists have differing opinions on whether one can change their metabolism.
• Essential nutrients cannot be created by the body, while non-essential ones can.
• Fortified foods have nutrients added that weren't originally present, like vitamin B in cereal.
• Enriched foods have nutrients added back after processing, such as calcium in soy milk.
• Phytochemicals are plant compounds with various effects on body functions, playing an important role in health but aren't considered a nutrient, examples include antibacterials and antioxidants.
• A calorie is a unit of energy and the amount of energy needed to raise the temperature of 1 kg of water by 1 degree Celsius.
• Macronutrient calorie content per gram:
  • Carbs: 4 calories per gram
  • Protein: 4 calories per gram
  • Fat: 9 calories per gram
  • Water: 0 calories per gram
• Calculating Total Calories from Macronutrients:
  • Determine total daily calories needed (e.g., 2,500 for a recreational athlete).
  • Calculate the calorie percentage from carbohydrates (e.g., 55%).
  • Multiply total calories by the carbohydrate percentage (e.g., 2,500 x 0.55 = 1,375 calories from carbs).
  • Convert the calculated calories from carbohydrates to grams daily (e.g., 1,375 calories / 4 calories per gram = 344 grams).
• Acceptable Macronutrient Distribution Ranges (AMDRs):
  • Carbs: 45-65%
  • Fat: 20-35%
  • Protein: 10-35%
• Athletes may require different AMDRs due to higher energy needs from increased exertion.
• Calculating adjustments to daily values should be done relative to a 2000 calorie diet.
• Fats have more carbon atoms than carbs or proteins, yielding a larger energy output (9 calories per gram vs. 4).
• Nutrient density refers to the nutrient content of a food relative to its calories. Foods with lots of vitamins/minerals and few calories are considered dense.
• Daily Value percentages are based on a 2,000 calorie diet:
  • 5% or less is considered low
  • 20% or more is considered high
• Determining Macronutrient Content:
  • Grams of each macronutrient x kcal/g = kcal, then divide by total kcal to get the macronutrient percentage.
• Example macronutrient breakdown:
  • CHO: 15g x 4 kcal/g = 60 kcal (60/81 = 74.1%).
  • PRO: 3g x 4kcal/g = 12 kcal (12/81 = 14.8%).
  • FAT: 1g x 9 kcal/g = 9 kcal (9/81 = 11.1%).
  • TOTAL: 81 kcal (100%).

Lecture 3: Nutrition, Guidelines, and Dietary Classifications

• Nutritional status relates to health as influenced by nutrient intake and use.
• Health is evaluated by a doctor or dietician with food and nutrient intake assessments, evaluations of physical health, reviews of medical and family history, and blood tests.
• Dietary guidelines address issues like obesity, diabetes, and overconsumption, centered on achieving a balanced plate as represented by MyPlate.
• Dietary Reference Intake (DRI:) It's an umbrella term for four nutrient classifications.
• Recommended Dietary Allowance (RDA):
  • Daily dietary intake level sufficient to meet nutrient requirements for nearly all healthy people.
  • Represents an Intake Goal.
• Estimated Average Requirement (EAR):
  • Average nutrient amount needed by healthy individuals.
  • Applicable to only 50% of the population.
  • Used by professionals for assessing nutrient adequacy in research groups.
• Adequate Intake (AI):
  • Used when RDA can't be determined.
  • Estimates amounts needed to sustain health.
  • Represents an Intake Goal.
• Tolerable Upper Intake Level (UL):
  • Maximum daily nutrient intake unlikely to pose health risk for most and cautions agains excess consumption.
• Four Dietary Guidelines exist.
• Variables affecting energy needs: age, gender, height, weight, and activity level.
• Daily Values (DV) comprise Reference Daily Intakes (RDI) and Daily Reference Values (DRV).
• A DV% was developed in 1990 by the FDA to include the product's nutrient content on nutrition labels, so consumers could understand how a product contributes to their total daily nutrient needs.
• Dietary Guidelines for Americans includes food groups such as:
  • Vegetables
  • Fruits
  • Dairy
  • Protein foods
  • Oils
• MyPlate emphasizes:
  • Proportionality
  • Variety
  • Moderation
  • Consumption of nutrient-dense foods
  • Grains
  • Vegetables
  • Fruits
  • Dairy
  • Protein

Lecture 4: Carbohydrates

• Carbohydrates consist of a carbon backbone with attached oxygen and hydrogen atoms.
• Glucose, as well as other carbohydrates that exist in nature, are synthesized by plants through photosynthesis.
• Construction of a carbohydrate comes from the sun, where light energy iscaptured to construct a carbohydrate.
• Constructed by combining carbon dioxide from the air and water form the soil to create simple sugars.
• Carbohydrates comprise simple sugars, or monosaccharides:
  • Disaccharides: 2 linked simple sugars
  • Oligosaccharides: 3 to 10 linked complex sugars)
  • Polysaccharides: 11 or more linked complex sugars)
• Carbohydrates function as energy source.
• Simple carbs
  • Glucose is important and common:
    • Rarely exist as a monosaccharide in food
    • Main source of energy
  • Fructose:
    • Abundant in fruit, honey, veggies
    • Sweetest
  • Galactose:
    • Sugar in milk
    • Found in fruits and veggies
• Complex carbs
  • Starch, found in plant cells
    • Amylose: straight-chain polymer
    • Amylopectin: highly-branched polymer
  • Glycogen:
    • Storage form of carbs in animals
    • Structure similar to amylopectin
    • Easily broken down
  • Starch
    • Grains, legumes, potatoes, and yams
  • Fiber:
    • All plants have
    • Most is indigestible by the body
• Simple carbs digest more quickly and provide immediate energy.
• Complex carbs digest more slowly and provide long-term sustained energy as opposed to simple carbohydrates.
• In short-term fitness activity, simple carbs are best.
• In longer term fitness activity, complex carbs are best.
• Recommended fiber intake per day for adults aged 19-50::
  • Males: 38 grams
  • Women: 25 grams
• Glucose aids in cellular respiration for glycolysis and ATP production, as well as promoting cell division, protein synthesis, active transport, muscle cell contraction, and transmission of nerve impulses.
• Salivary amylase breaks down carbs in the mouth. Most carb digestion occurs in the small intestine.
• Active transport is how glucose is transported, requiring energy and transporter proteins, but the transport is not determined by concentration gradients.
• Diabetes results from the inability of beta cells to produce enough insulin to lower blood glucose levels, meaning the body's tissue does not respond normally.
• Excess glucose stored as fat through De Novo Lipogenesis: Glucose is converted to fatty acids and then binds to a glycerol molecule to form triglycerides (fat).

Lecture 5: Lipids

• Lipid: Chemical term for fat.
• 3 Types of lipids:
  • Triglycerides (most common)
  • Sterols
  • Phospholipids
• A triglyceride contains three fatty acids and a glycerol backbone.
• Saturated fats:
  • Carbon atoms are saturated with hydrogen atoms, therefore no other atoms can attach.
  • Found in plant and animal products
• Unsaturated fats:
  • Not all of the carbs have hydrogen atoms attached.
• The level of hydrogen saturation of carbons is directly related to whether they are a solid at room temperature.
• Triglycerides transported via passive diffusion:
  1. Lingual lipase is released in saliva to initiate the enzymatic digestive process
  2. Lingual lipase is then denatured by stomach acid
  3. After 2-4 hours in the stomach, one-third of the dietary triglycerides have been broken down into diglycerides and free fatty acids
  4. Fat globules enter the SI and breakdown via emulsification
  5. Pancreatic lipase breaks the globules into short/medium-chain fatty acids which will be broken down into micelles as a result of bile salts
  6. Pass the intestinal cells and diffuse into capillaries -> iinto bloodstream
• Lipids provide:
  • texture
  • flavor
  • aroma
• Lipids are also necessary for membrane function, vitamin D synthesis, absorption of fat-soluble vitamins, long-term energy storage, and insulation.
• Lipids cushion organs and act as lubricant for nerves/neurons, steroid hormones like testosterone and estradiol.
• The average American diet is 1:1 or 4:1 for omega 6 to omega 3.
• Phospholipids are lipids containing a phosphate group and are present in small amounts in food and the body.
• Sterols are lipids found in plants and animals: e.g., cholesterol/phytosterol.
• High-density lipoproteins (HDL) pick up excess cholesterol and return it to the liver, carrying less triglycerides and more proteins; versus low-density lipoproteins (LDL) carry lipids made in the liver and distribute them to the body with less proteins and more triglycerides.
• HDLs are considered “good cholesterol” for preventing cholesterol deposition in artery walls.
• LDLs are considered “bad cholesterol” as they are associated with the risk of atherosclerosis and cardiovascular disease (CVD).
• Modifiable Risk Factors for Heart Disease:
  • Diabetes
  • High Blood Pressure
  • Obesity
  • Hypercholesterolemia
  • Lifestyle
  • Smoking
  • Sedentary behavior
  • Diet
• Non-modifiable Risk Factors for Heart Disease:
  • Age
  • Gender
  • Genetics

Lecture 6: Protein

• Proteins are macronutrients containing molecules made up of one or more chains of amino acids. There exist hundreds of different types of proteins.
• Proteins function in the synthesis of enzymes and hormones, tissue repair and maintenance, transportation and storage, act as antibodies, support overall biological processes, and can be used as energy (last resort).
• Structures of protein shapes include:
  • Collagen: elongated for strength
  • Hemoglobin: spherical shape to bind oxygen
  • Muscle: linear, for muscle contractions
• Amino acid structure include:
  • Carbon
  • Hydrogen
  • Acid
  • Amino (nitrogen-containing)
  • Side chain (R group) Essential amino acids can't be made in the body (9), whereas non-essential amino acids can (11).
• Branched-chain amino acids (BCAAs) comprise 3 essential amino acids: Leucine, Isoleucine, and Valine.
• Protein is transported via facilitated diffusion/active transport.
• There is no chemical digestion of protein in the mouth when compared to carbs and lipids, only chewing to physically break it down.
• Protein synthesis builds proteins through a series of steps:
  1. Nucleus: The series of A and T in specific order will tell enzyme where to bind
  2. Transcription: RNA copies DNA, creating mRNA
  3. RNA splicing: Takes pieces of mRNA and puts it back together
  4. Translation: mRNA moves out of nucleus and into Ribosomes, binding with tRNA
  5. tRNA: One end contains amino acids and the other end contains 3 nitrogenous bases
  6. Translated into groups of 3, forming polypeptide chain
  7. Folding: Chain folding
• Protein catabolism breaks down complex molecules into smaller units only to release energy when there is not enough calorie consumption.
• The fate of amino acids: amino acids can be converted into glucose or fatty acids, or become parts of proteins and other Nitrogen containing compounds.
• Protein-energy malnutrition (PEM) causes loss of fat and muscle mass, alongside an increased risk of infection.
  • Kwashiorkor: pure protein deficiency
  • Marasmus: overall energy deficiency
• To maintain nitrogen balance, there needs to be balanced levels of nitrogen from protein intake, and from excretion in urine, feces, and sweat.
• RDA Requirements include 0.8 g/kg of body weight for healthy adults, so more weight requires more protein to maintain and repair.
• For a 70 kg adult, the daily protein requirement stands at 56 g, while the average consumption is 70 g/day!
• Higher protein needs may be required for the following:
  • Infants
  • Pregnancy and lactation
  • Athletes
  • Injuries
• Athletes at most risk for protein deficiency are those with low energy intakes like:
  • Female endurance athletes
  • Male wrestlers
  • Male and female gymnasts
  • Female dancers
• Protein needs of athletes are dictated to by the following training regimens:
  • Endurance training: 1.2-1.4 g/kg/day of protein
  • Resistance training: 1.2-1.7 g/kg/day of protein
• Complete proteins contains all 9 AAs, easier to digest (animals, quinoa, soy) vs incomplete proteins, which lack one or more essential AAs and are harder to digest (most plants).
• Excess protein intakes of > 3 g/kg/day over long periods of time can result in:
  • Dehydration
  • Kidney issues (dysfunction, kidney stones)
  • Bone health issues
  • Raised risks of heart disease and cancer
• Protein needs based on recommendations:
  • 0.8 g/kg BW for healthy people
• The more weight, the more protein needed to maintain and repair
• 70 kg (154 lb) adult= 56 g of protein/day
• Average consumption = 70 g of protein/da