TAMU Nutrition 202 Exam 2

3 major categories of lipids

triglycerides, phospholipids, sterols

saturated fats structure

carbon atoms have 4 single covalent bonds, allowing for maximum hydrogen bonding

monounsaturated fats structure

one double bond

polyunsaturated fats structure

more than one double bond

sources of saturated fatty acids

coconut oil, palm kernel oil, cheese, butter, pork, poultry with skin

sources of unsaturated fatty acids

vegetable oils, nuts and seeds, fish

sources of trans fatty acids

margarine and shortening

sources of cholesterol

animal products

2 essential fatty acids

linoleic acid (omega-6) and linolenic acid (omega-3)

sources of omega-6

soybeans, corn, safflower oils, vegetables, fruits, seeds, grains

sources of omega-3

flax seed and oil, pumpkin seed, walnut oil, green leafy vegetables, walnuts, canola oil, fatty fish

role of Omega-6 fatty acid in health maintenance

reproduction and blood flow

role of omega-3 fatty acid in health maintenance

prevent tissue inflammation, reduce heart disease and blood clot formation

function of lipids in the body

Energy storage, primary energy source for heat, absorption of fat-soluble vitamins, protection and isulation of vital organs, regulate body temperature

fat blocker

disrupts intestinal fat absorption, inhibit digestive enzyme that breaks down triglycerides

side effects of fat blockers

anal leakage, reduced fat-soluble vitamin A, D, E, and K absorption, malabsorption of oral contraceptives

4 types of lipoproteins

chylomicrons, VLDL, LDL, HDL

type of lipid in chylomicrons

triglycerides

type of lipid in VLDLs

triglycerides and cholesterol

type of lipid in LDLs

bad cholesterol

type of lipid in HDLs

good cholesterol

LDL and heart disease

high levels of LDL raise risk for heart disease

HDL and heart disease

high levels of HDL lower risk for heart disease

Dietary Guidelines for Americans recommendation on fat intake

20-35% of daily calories from fat; intake below this range is not recommended and can lead to decreased absorption of fat-soluble vitamins

foods consumed in Mediterranean diet

-High intake of olive oil, nuts, vegetables, fruits, and mainly whole grain cereals
- Moderate intake of fish and poultry
- Low intake of dairy products, red meat, processed meats, and sweets
- Wine in moderation, consumed with meals

fats associated with increased incidence of cancer and heart disease

high levels of saturated fats

fats associated with reduced incidence of cancer and heart disease

fatty fish and fish oil high in omega-3 fatty acid

elements that make up amino acids

carbon, hydrogen, oxygen, nitrogen

essential amino acids

must be consumed in the diet

non-essential amino acids

made by body in adequate amounts

Transamination

transfer of amine group from one molecule to another to create an amino acid

conditionally essential amino acids

amino acids that are normally considered nonessential but become essential under certain circumstances when the body's need for them exceeds the ability to produce them

Functions of protein in the body

hormones, growth/maintenance/repair, body structure and blood, fluid balance, transport, acid base balance, immune function, enzymes

positive nitrogen balance

intake > excretion (occurs during growth, recovery from illness and during pregnancy)

negative nitrogen balance

excretion > intake (occurs during AIDS, cancer, starvation, muscular dystrophy, and low-calorie/protein diets)

potential health benefits associated with vegetarian diets

decrease risk of heart disease and rates of obesity

potential nutritional deficiencies associated with vegetarian diets

vitamin B12, zinc, iron, calcium, vitamin D, protein

incomplete proteins

lack one or more of the essential amino acids

complete proteins

contain all essential amino acids

complementary proteins

help complete incomplete proteins, amino acid contents combined provide all essential amino acids

sources of incomplete proteins

Grains and items made from grains, Vegetables, Legumes, Nuts and Seeds, Gelatin

sources of complete proteins

Meat, Poultry, Seafood, Milk, Yogurt, Cheese, Eggs, Soybeans, Soybean Products

sources of complementary proteins

nuts, seeds, legumes

RDA for protein

0.8 g/kg of body weight

population/ groups that may need additional protein

growing children and adolescents, women who are pregnant, lactating women, athletes, injured, ill

protein energy malnutrition

A disorder caused by inadequate consumption of protein. It is characterized by severe wasting.

marasmus

a condition of starvation related to deprivation of all food, characterized by emaciation or skeletal appearance

Kwashiorkor

characterized by swollen appearance, especially in the abdomen; caused by low protein intake, altered gut bacterial populations, frequent in children being weaned from breast milk to cereal

diets containing plant-based protein and influence on cardiovascular disease

plant based protein intake has an inverse relationship with systolic and diastolic blood pressure

diets containing animal-based protein and influence on cardiovascular disease

animal based protein has a posititve association with blood pressure

type of research studies conducted to investigate the effects of plant and animal based protein on cardiovascular disease risk and occurrence

observational

strengths of research studies conducted to investigate the effects of plant and animal based protein on cardiovascular disease risk and occurrence

most of the studies yielded the same results

weaknesses of research studies conducted to investigate the effects of plant and animal based protein on cardiovascular disease risk and occurrence

inconsistent findings and potential confounders inherent to observational studies

relationship between energy balance and bodyweight

Energy balance is the energy taken in and the energy taken out. If the net of energy balance is negative, the body weight should decrease. If the net of energy balance is positive, the body weight should increase. (More energy taken in than given off)

Components of total energy expenditure

basal metabolism, physical activity, and thermic effect of food

BMI (body mass index)

weight (kg) / height (m^2)

underweight

healthy weight

18.5-24.9

overweight

25-29.9

obese

>30

limitations of BMI

does not distinguish between fat and muscle mass, various ethnicities, sex, elderly

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

components of body composition

lean tissue mass + fat mass + water

relationship between location of excess body fat and risk of chronic disease and mortality

gynoid pattern: fat over muscle and under skin at hips and things (subcutaneous fat)
android pattern: visceral fat is associated with increased risk for chronic conditions due to excess fat

causes of obesity

energetics, environment, genetics, hormone imbalance

energenetics

eating more calories than burning

environment

sedentary lifestyles and income

genetics

set point theory, metabolism, adipocytes growth, hormone imbalance

hormones and neurotransmitters that influence hunger/appetite and weight status

neuropeptide Y: compound that increases food intake and blood glucose levels, promoting energy storage in fat cells
ghrelin: hormone produced by cells lining the stomach when stomach is empty that cause increased hunger

hunger

need to eat; triggered by low blood glucose and low glycogen

appetite

desire to eat; triggered by sight/smell of food

Why are fad diets unsuccessful in the long term?

Unrealistic and difficult to follow long term
Many categorize foods as "good" or "bad" and encourage dieters to eliminate certain foods

recommendations for successful lon-term weight loss and maintenance in adults

promote small moderate lifestyle changes, reduce energy in and increase energy burned, lower portion size and increase dialy physical activity

weight loss surgeries

Sleeve gastrectomy: removes part of the stomach
Gastric bypass: small pouch created from stomach
Gastric banding: adjustable band fits around upper part of stomach

2 compartments in which water is found

intracellular: 60% of body water (cytoplasm)
extracellular: 40% of body water (interstitial fluid and intravascular fluid)

sources of water intake

-Beverages, food, metabolic water
-from breakdown of carbohydrates, fats, and proteins
-1 to 1 1/2 per day

sources of water loss

urine
sweating
lungs
feces
insensible losses

how is water retention and intake regulated in the body?

hypothalamus, antidiretic hormone, aldosterone

hypothalamus and hydration

controls body's need for water; triggered when water levels in blood decrease and solute concentration increase

antidiuretic hormone (ADH)

released by pituitary gland to signal kidneys to retain water

aldosterone

produced by adrenal glands, induces kidneys to retain sodium and water

dehyration

excessive loss of body water

Hyponatremia

low sodium in the blood; water intoxication

function of water and electrolytes in body

- water and electrolyte balance: water and electrolytes are moved across cell walls through diffusion and osmosis
- acid-base balance: maintenance of normal blood pH
- nerve transmission: assist in fucntion of excitable cells in nerves
- gastric pH: hydrochloric acid contains chloride for protein digestion and absorption of some minerals

Osmosis

movement of water across a membrane from area with fewer particles to area with more particles

diffusion

movement from area of greater concentration to area of lesser concentration

3 high sodium foods

pickle, chicken broth, corned beef

3 high potassium foods

potato, avocado, bran buds

Adequate Intake (AI) for water

1-1.5mL of energy expenditure

DASH diet

increased fruits and vegetables to increase potassium
increased whole grains to increase magnesium
low fat dairy to increase calcium
lower saturated fat