Nutrition 202 Exam 2

Module 5 – Fats/Lipids

• List the major classes/categories of lipids.

  • Triglycerides

  • Phospholipids

    • ex: emulsifiers

  • Sterols 

    • ex: cholesterol, vit D, sex hormones

• Distinguish between the structures of saturated, monounsaturated, and polyunsaturated.

  • saturated

    • carbon chain is fully occupied by hydrogen atoms

    • solid at room temperature

  • monounsaturated

    • a fatty acid with one double bond 

    • liquid at room temp

  • Polyunsaturated

    • fatty acid with 2 or more double bonds

    • liquid at room temp

• What are common dietary sources of: 1) saturated; 2) unsaturated; 3) trans fatty acids; and 4) cholesterol in the American diet?

• Primary sources

  • Saturated

    • beef, pork, poultry with skin, and other meats

    • cheese, butter, and other dairy products

    • palm and coconut oils (tropical oils)

  • Unsaturated

    • Vegetable oils

    • Nuts and Seeds

    • Fish

  • Cholesterol

    • only in animal products

  • Trans fatty acids

    • store-bought cakes, cookies, and crackers

    • margarine and shortening 

    • a small amount found naturally in dairy products, milk,  and meat

• List the two essential fatty acids and identify two dietary sources of each.

  • Omega-6

    • most common form is Linoleic acid

    • Dietary sources: Soybean, corn, and safflower oils; vegetables, fruits, seeds, grains

  • Omega-3

    • most commonly found as Linolenic acid and Eicosapentaenoic/Docosahexaenoic acid

    • Dietary sources for Linolenic acid: flax seed/oil, pumpkin seed, walnut oil, green leafy veggies, walnuts, canola oil

    • Dietary sources for EPA & DHA: Fish (lake trout, herring, sardines, Atlantic salmon, albacore tuna, bluefish, halibut, and mackerel. DHA found in breast milk

• What is the role of omega-6 and omega-3 fatty acid products in health maintenance?

  • Omega-6

    • incorporated into cell membranes

    • precursors to compounds involved in repro and blood flow

  • Omega-3

    • in cell membranes

    • helps prevent tissue inflammation and may prevent heart disease and blood clot formation

• What functions do lipids perform in our bodies and foods? (6 functions)

  • Energy source

    • the primary energy source for the heart in the stored form

    • supplies about 60% of ongoing energy during rest

  • supply of essential fatty acids

    • Omega-6 and Omega-3

  • absorption & transport of fat-soluble vitamins

    • fat is required for the absorption of fat-soluble vitamins

      • Vitamins A, D, E, K

  • organ insulation and protection

    • protects vital organs

      • ex: fat deposits located around the kidney

    • females have a greater % body fat than males

  • precursor to steroid hormones

    • Specifically a precursor via Cholesterol

      • hormones => estrogen, testosterone, aldosterone

      • Vitamins => Vit D

  • sensory quality of food and human satiety. 

    • In foods

      • mouthfeel, texture, and flavor compounds interact with fat molecules in food

    • Fat causes you to feel full longer

      • satiety

      • fat slows stomach emptying

      • enhances flavor compounds

• Identify the type of lipid (cholesterol, triglycerides, etc.) carried by each of the four lipoproteins.

  • Lipoproteins

    • spherical structures that are composed of lipids and proteins, transport lipid particles in the body

    • outer shell is a monolayer made of proteins and phospholipids

  • 4 types:

    • Chylomicrons

      • made in small intestine

      • transports dietary lipids to the liver

    • Very low-density lipoproteins (VLDLs)

      • synthesized in the liver

      • contains both triglycerides and cholesterol

      • deliver triglycerides to other tissues

    • Low-density lipoproteins (LDLs)

      • formed after VLDLs deposit triglycerides in other tissues

      • cholesterol-rich

      • deliver cholesterol to other tissues, including blood vessels (bad cholesterol)

    • High-density lipoproteins (HDLs)

      • made mostly in the liver and a little in the small intestine

      • removes excess cholesterol from cells and returns cholesterol to the liver for elimination (good cholesterol)

• Describe the relationship between LDL and HDL levels and heart disease risk.

  • LDL 

    • can build up cholesterol and create plaque in the artery wall

    • high levels => higher risk of heart disease

  • HDL

    • transports excess cholesterol from the bloodstream and transports it back to the liver removal

    • high levels => lower risk of heart disease

• What are the Dietary Guidelines for Americans' recommendations on dietary fat intake?

  • 20-35% of daily calories from fat, children under 2 need more (30-35%)

  • Saturated fats need to be less than 10% of total calories and be replaced with polyunsaturated/monounsaturated fatty acids

  • to minimize trans fats and products with hydrogenated fats found in crackers, snack foods, readymade cakes/cookies, margarine/shortening

  • Consume less

    • High-fat meat, pork, lamb, and poultry with skin on

    • cheese and whole-fat diary

    • processed meats

    • butter/margarine

  • Consume more

    • fruits, veggies, whole grains

    • nuts, seeds

    • low fat or non-fat diary

    • liquid vegetable oils

    • lean meat, pork, lamb, poultry without skin and fatty fish

• How does the Mediterranean diet compare to the typical Western/American diet? What foods are consumed in the Mediterranean Diet?

  • Mediterranean

    • whole unprocessed foods

    • A heart-healthy eating pattern based on traditional diets of countries bordering the Mediterranean Sea, emphasizing whole foods, healthy fats, and an active lifestyle

  • Western 

    • convenience foods

  • Types of food in Mediterranean diet:

    • Fruits and vegetables

    • Whole grains

    • Healthy fats

    • Lean proteins

    • Diary in moderation

    • Herbs and spices

    • Red wine (in moderation/not required)

• What types of fats are associated with increased incidence of cancer and heart disease?

  • Cancer

    • Saturated fats

    • associated with a high incidence of breast, ovarian, colon, and prostate cancer

  • Heart Disease

    • total fat, saturated fat, trans fat

• What types of fats are associated with reduced incidence of cancer and heart disease incidence?

  • Cancer

    • Fatty fish and fish oil high in Omega-3 fatty acids

    • associated with a low incidence of colon, breast, lung, esophageal, skin, and pancreatic cancer

  • Heart Disease

    • Unsaturated fats both mono and poly?

Mediterranean Diet

• Bolded Terms and definitions

  • Diet => the nutrients/foods consumed

  • Dietary patterns => include when the food is eaten, how it is portioned, and other lifestyle factors

  • macronutrient distribution of med diet:

    • 28%-40% fats

    • 40%-65% carbs

    • 10%-35% proteins

  • different distribution of fats in the diet but not lower

    • higher Omega-3 fatty acids (fatty fish and fish oil)

    • higher monosaturated fat (extra virgin olive oil)

    • higher levels of polyunsaturated fat

    • lower levels of saturated fat

  • Adherence => the extent to which an individual follows a diet or dietary pattern in the long term, influenced by both dietary and lifestyle components

  • Built environment => the layout and design of human-made surroundings where people live, work, and play. This includes the design of the neighborhoods, streets, and buildings, and the availability of food options. This can impact the dietary choices available and the level of physical activity, therefor health. 

• Main dietary components

  • increased amount and variety of veggies, fruits, and nuts

  • daily consumption of whole grain products (bread, pasta, rice)

  • moderate intake of fish, seafood, and non-red meats

  • use of olive oil as the main cooking oil

  • higher use of aromatic herbs and spices compared to use of salt

  • focus on the quality, freshness, seasonality, and simplicity of food

  • drinking wine in moderation

• Main lifestyle components

  • moderation in portion size, timing, and pace of meals

  • moderate physical activity every day (not just the gym but also walking and using public transportation)

  • cooking and consuming meals in the company of others

  • adequate rest

Module 6 - Proteins

• What elemental units make up amino acids?

  • Amino group, Acid group (carboxyl), Hydrogen group, and R group (side chain)

  • Nitrogen, Carbon, Hydrogen, Oxygen

• Define essential, non-essential, and conditionally essential amino acids.

  • Essential amino acids 

    • Cannot be synthesized by the human body

    • Must be supplied by food

    • Are vital for many processes, including protein synthesis, energy production, and immune function

  • Nonessential amino acids 

    • Can be produced by the human body

    • Do not need to be consumed in food

  • Conditionally essential amino acids 

• Are not normally required in the diet

• Become essential in times of illness or stress

• List the functions of protein in the body.

  • Growth/Maintenance/Repair

    • Protein turnover

      • 2 parts: Synthesis & Breakdown

  • Hormones

    • messengers that help regulate the various systems and functions of the body. 

    • Ex: Insulin is made of protiens

  • Body structure and blood

  • Fluid balance

    • proteins in blood maintain the optimal balance between the fluids inside and outside cells and blood vessels

    • Albumin - the most abundant protein in the blood

      • helps protein concentration similar to that of cells

      • Edema develops when blood albumin is low because there is a decrease in the intake of protein which pushes water out to the tissues.

  • transport

    • Transport across cell walls via pumps

      • Sodium-Potassium pump

    • Transporter of nutrients through the bloodstream

      • Retinol-binding protein

    • Proteins have water-repelling and water-attracting ends which allows for interactions with both water and fats 

      • ex: lipoproteins that are usually found in the phospholipid bilayer

  • acid-base balance

    • proteins act as buffers (albumin/hemoglobin) to help maintain the pH/acid-base balance of the body

  • Immune function

    • proteins make up Antigens that interact with foreign substances to trigger an immune response

    • Proteins make up the body’s 1st line of defence Skin (collagen), Mucous, Enzymes

    • Proteins produced by the immune system in response to the antigen are called Antibodies and are made by WBCs.

  • Enzymes

    • speeds up chemical reactions, made of proteins

• Describe situations in which a person would be in a) positive nitrogen balance and b) negative nitrogen balance.

  • Positive nitrogen balance

    • intake exceeds excretion

    • the body needs more protein to be able to build new tissues

    • occurs during growth, recovery from illness, and pregnancy

  • Negative nitrogen balance.

    • excretion exceeds intake or intake is inadequate to meet the body’s needs

    • the body is breaking down more protein

    • occurs during AIDS, Cancer, starvation, muscular dystrophy, and low-calorie protein diets

• What are the potential health benefits and nutritional deficiencies associated with vegetarian diets?

  • benefits

    • decrease the risk of heart disease

    • decrease rates of obesity

  • potential nutritional deficiencies

    • Protein

    • Zinc

    • Iron

    • Calcium/Vit D

    • Vit B12

    • Iodine

• Define complete, incomplete, and complementary proteins.

  • Complete/High quality

    • provides all essential amino acids in amounts needed by the body

    • easily digested and absorbed

  • Incomplete proteins

    • do not contain all essential amino acids in the amount required by the body

  • Complementary proteins

    • amino acid contents combined provide all essential amino acid

    • ex: grains are limited in lysine so you add legumes to have a complete AA 

• List 3 dietary sources of complete proteins, 3 dietary sources of incomplete proteins, and 3 dietary sources of complementary proteins.

  • Complete

    • Dairy, Fish, Poultry, whole sources of soy (tofu & edamame)

  • Incomplete

    • Legumes, grains, and vegtables

  • complementary

    • rice and beans, peanut butter, nuts and seeds

• What is the RDA value for proteins for healthy adults?

  • 0.8 g per kg

• What populations/groups of people may need additional protein?

  • growing children and adolescents

  • women who are pregnant

  • lactating women

  • athletes 

  • those who are injured or ill

• Compare and contrast protein-energy malnutrition, marasmus, and kwashiorkor.

  • Marasmus

    • condition of starvation characterized by emaciation or skeletal appearance

    • caused by inadequate protein and calorie intake 

  • Kwashiorkor

    • characterized by a swollen appearance, specifically in the abdomen

    • proposed causes

      • low protein intake; altered gut bacterial populations

      • frequent in children being weaned from breast milk to cereal

      • usually enough calories but not enough protein so there is a fluid shift because of decreased levels of albumin. 

Module 7 – Obesity and Energy Balance

• What is the relationship between energy balance and body weight?

  • weight management is related to kcal in vs kcal out

  • a negative energy balance = kcal consumed is less than kcal expended

    • weight loss

  • a positive energy balance = kcal consumed is greater than kcal expended

    • weight gain

• What are the components of total energy expenditure?

  • Basal metabolic rate (BMR)

  • Physical activity

  • Thermic effect of food (TEF)

• Evaluate BMI to determine if an individual is underweight, normal weight, overweight, or obese.

  • weight in kilos/(height in meters)^2

  • classifications

    • under 18.5 => underweight

    • 18.5-24.9 => healthy

    • 25-29.5 => overweight

    • over 30 => obese

• What are the limitations of BMI?

  • it doesn’t distinguish between fat and muscle mass

    • athletes (less body fat => high lean body mass)

    • Ethnicities (body fat & disease risk)

    • sex (same BMI women tend to have more body fat than men)

    • Elderly (tend to have more body fat than younger adults)

• Identify factors that influence energy burned during physical activity.

  • body weight and muscle mass utilized

  • duration of activity

  • intensity of activity

  • fitness level

  • Type of Activity

• What are the components of body composition?

  • Total body mass/body weight = lean tissue mass + fat mass + water

  • categories of body fat

    • essential => required for normal physiological functions

    • storage => fat in adipose tissue, tissue under the skin, and fat that “pads” essential organs

  • % body fat differs with age, sex, and body needs

    • body fat inc with age

    • women have a higher percentage

    • athletes tend to have a lower body fat

    • women in pregnancy (pre- & post) tend to have more

• What is the relationship between the location of excess body fat and the risk of chronic disease and mortality?

  • Gynoid (pear-shaped)

    • fat over muscle and underskin at hips and thighs

    • subcutaneous fat

      • stored under the skin, less association with health risks

      • temperature regualtion

  • Android (apple-shaped)*

    • stored under the abdominal muscle around the internal organs

    • visceral fat

      • contributed to heart disease & diabetes

      • waist circumference greater than 35inch in women and 40inch in men

    • associated with risk for chronic conditions due to excess fat 

• What are the causes of obesity in our society?

  • energetics

    • positive energy balance from eating more calories than you burn

  • environment

    • as a society, we move less and eat more 

    • social network is obese

    • healthy & affordable food is sometimes hard to purchase

  • Genetics

    • set point theory => body is programmed to gravitate towards a particular weight

    • when a person gains weight in the form of fat both the number and size of fat-storing cells (adipocytes) increase. 

• Identify hormones and neurotransmitters that influence hunger/appetite and weight status.

  • Leptin

    • released by fat cells to signal the brain that the body has had enough to eat

    • Inc in Leptin results in a decrease in food intake and an increase in energy metabolism

    • long term weight control

  • Neuropeptide Y

    • a neurotransmitter that increases food intake (stimulated appetite) and blood glucose levels, promoting storage of energy in fat cells and diminishing energy expenditure. 

  • Ghrelin

    • a hunger-stimulating hormone produced by cells lining the stomach when the stomach is empty

    • increases hunger

    • after eating, levels decrease

    • Ghrelin increases with fasting, hunger, starvation, and weight loss

• What is the difference between hunger and appetite?

  • Hunger is the need to eat

    • trigger by low blood glucose and low glycogen

  • Appetite is the desire to eat

    • triggered by the sight/smell of food

• Why are fad diets unsuccessful in the long term?

  • Unrealistic and difficult-to follow long term

  • categorize foods as “good” or “bad” and encourage dieters to eliminate certain foods

  • inconsistency in research data to have a unified approach 

• Identify recommendations for successful long-term weight loss and maintenance in adults.

  • establish diet and physical activity plans that can be followed for a lifetime

  • promote small, moderate lifestyle changes

  • dec. portion size and inc. daily physical activity

• What are the general recommendations for treating childhood obesity?

  • weight maintenance

  • gain height and grow into their weight

  • profs don’t recommend caloric restriction because it can inhibit growth during rapid development phases