nutrition CH6&7 LOs
describe major functions of lipids in the body (7)
1- absorb fat-soluble vitamins & phytochemicals 2- cushion the body against bumps & blows 3- form & maintain cell membrane 4- form body contours 5- insulate the body against cold temperatures 6- produce steroid hormones 7- provide & sotre energy (triglycerides)
name two plant oils that are high in saturated fats
1- coconut oil 2- butter fat
name the elements that are found in all proteins (4)
1- hydrogen 2- carbon 3- oxygen 4- nitrogen
identify the acceptable macronutrient distribution range (AMDR) for protein intake in healthy adults
AMDR intake is 10-35% of energy from protein
describe protein denaturation, and identify the factors that cause proteins to denature
denaturation = altering a protein's natural shape and function by exposing it to conditions such as heat, acids, and physical agitation denature by: alcohol, heat, acidic lemon juice
list total dietary fat, saturated fat, trans fat, & cholesterol intake recommendations
**2000 - kcal diet total fat = 20-30% of total calories (45-75g total fat) saturated fat = less than 10% of total calories (22g total fat) trans fat = keep intakes as low as possible cholesterol = as little as possible while consuming a healthy diet
discuss the pros and cons of vegetarian diets
- (+) vegetarian have lower risk of obesity, type 2 diabetes, hypertension, and certain cancer - (+) vegetarian have more fiber, phytochemicals, folic acid (B vitamin), vitamin E & C, minerals like potassium & magnesium - (-) vegetarian have low vitamin B-12, D, and riboflavin, zinc, iron, & calcium, omega-3 fatty acid, certain essential amino acids, energy
compare the percentages of saturated, monounsaturated, and polyunsaturated fatty acids in animal-derived fats with those in most plant-derived fats
- fat in beef and dairy products contains more saturated than unsaturated fatty acids --olive oil rich source of MUFA; liquid corn oil has higher proportion of unsaturated than saturated -beef and dairy has higher percentage of SFA that most plant fats -tropical oils (coconut and palm oil) contain more saturated than unsaturated fatty acid
describe health consequences of overconsumption of protein
- heart disease and cancer are leading causes of death - high amounts of red meat & processed meats has been associated with increased risk of certain chronic disease, particularly heart disease, colorectal cancer, and diabetes - overconsumption can lead to chronic disease, cancer, many more
list the primary functions of proteins in the body
- to build new cells & many functional components of cells -as component of hardened structures (hair & nail) -as enzymes to speed chemical reactions -lubricants to ease movement -in clotting compounds in blood -to build antibodies that fight disease organisms -as compounds that help maintain fluid & pH balance -as transporters -to make certain hormones -as an energy source (minor function)
describe the incidence, causes, and treatment of food allergies
-Food allergy is an inflammatory response that results when the body's immune system reacts inappropriately to one or more harmful substances (allergens) in food -Most cases, food allergen is protein because some protein does not undergo complete digestion, and the small intestine absorbs the whole molecule -Immune system cells in the small intestine recognizes the food protein as a foreign substances and try to protect the body by mounting a defensive response. -Results of immune response, the individual experiences typical signs and symptoms of food allergy: hives, red raised bumps that usually appear on the skin, swollen or itchy lipids, scaly skin rash (eczema), difficulty swallowing, wheezing and difficulty breathing, and abdominal pain, vomiting, and diarrhea -treatment of food allergies involves strict avoidance of the certain food
summarize lifestyle factors that can reduce risk factors for developing atherosclerosis
-at least 5 days a week engage in a moderate-intensity physical activity -balance energy intake that can help maintain healthy body weight -eating healthier, eating rich source of fiber (soluble fiber) -reduce intake of carbohydrates -less alcohol intakes -losing excess weight
describe how proteins are absorbed by the digestive tract, and identify where they are transported after being absorbed
-digestion of proteins to amino acids, the amino acids are transported by specific carrier systems into the absorptive cells -after entering the absorptive cell, the amino acids move into the capillary of the vilus -undigested protein entering the large intestines and being excreted in feces -after being absorbed, the amino acids travel to the liver (hepatic portal vein) -the liver keeps some amino acids for its needs and release the rest into the general circulation
list the key roles of phospholipids in foods and in the body
-hydrophilic = part of a molecule that attracts water -hydrophobic = part of molecule that avoids water & attracts lipids -acts as an emulsifier --emulsifier = substance that helps water-soluble and water-insoluble compounds mi with each other -it a major component of cell membrane --cell membrane composed of a double layer that is mostly phospholipids --chemical structure of phospholipids enables the membrane to be flexible & function properly --normal functioning of nerve cells; including in brain
explain why celiac disease causes malabsorption in the small intestine
-it has poor absorption of nutrient -small intestine cannot absorption gluten to well
discuss protein digestion, including enzymes involved in the process
-protein digestion begins in the stomach -HCl denatures food proteins & activates pepsin from the inactive form of enzyme, pepsinogen -pepsin initiates enzymatic digestion of proteins into smaller polypeptides -after entering small intestine, the pancreas secretes proteins-splitting including trypsin & chymotrypsin -enzymes released by the absorptive cells of the small intestine break down most of the shortened peptides into di- & tri- peptides -when these come into contact with microvilli of villi, enzymes within the microvilli can break them down into amino acids. -making amino acids the end product protein digestion
summarize the major steps of lipid digestion and absorption, and identify the major digestive organs involved in the process
-triglyceride & phospholipid are broken down by lipase (enzyme that breaks down lipid) before absorption -fatty chyme leaves the stomach & enters the small intestine, stimulates to secrete secretin & cholecystokinin --secretin stimlates the liver to produce bile & causes the pancreas to secrete bicarbonate-rich pancreatic juice, which is necessary to create an alkaline environment in the small intestine --cholecystokinin (CCK) signals the pancreas to secrete digestive enzymes; triggers gall bladder to release bile & sphincter to control the flow of bile & pancreatic juice into duodenum to open -pancreatic lipase = digestive enzyme that removes two fatty acids from each triglyceride molecule -bile salt = component of bile, enhance lipid digestion & absorption -lipid absorption occurs in the small intestine (duodenum & jejunum) -this is a long chain -small intestine digests & absorbs nearly all of triglycerides & phospholipids in food, but only 50% of dietary cholesterol is absorbed
explain the basic steps of protein synthesis
To help visualize the process of protein synthesis, imagine proteins as various chains made from 20 different amino acid "beads" -Each bead is connected to another bead to form a chain -To make a copy of a particular beaded chain, you would follow directions for connecting the beads in a specific order and length by stringing each bead together. -In living things, the beaded chains are proteins that contain numerous amino acids ("beads") -Consider the vast variety of beaded chains comprised of different bead sequence and chain length that you could make from just 20 different beads
describe the basic chemical structure of an amino acid
amino acids = nitrogen-containing chemical units that comprise proteins - each amino acids has a carbon atom that anchors a hydrogen atom & 3 different groups of atoms: amino or nitrogen-containing group, R group, & carboxylic acid group amino or nitrogen-containing group = proportion of an amino acid that contains nitrogen R group(side chain) = part of an amino acid that determines the molecule's physicals and chemical properties carboxylic acid group = carboxylic acid portion of a compound
explain the process and health effects of atherosclerosis
atherosclerosis = long-term disease process in which plaque builds up inside arterial walls - attacks kidney, eyes, legs, brain, and heart - having 1 or more risk factors increasing chance of developing it - results in decreased arterial blood flow & arteriosclerosis - heart disease & stroke result from this arteriosclerosis = condition that results from atherosclerosis and is characterized by loss of arterial flexibility -arterial lining that is injured (by oxidation, infection, or nutrient deficiency) that results in atherosclerosis hypertension = abnormally high blood pressure levels that persist even when the person is relaxed
describe common causes of abnormal blood urea nitrogen and urine urea nitrogen levels
blood urea nitrogen (BUN) = measure of the concentration of urea in blood urine urea nitrogen (UUN) = measure of the concentration of urea in urine
distinguish between essential, conditionally essential, and nonessential amino acids
essential amino acids = amino acids the body cannot make or cannot make enough of to meet its needs conditionally essential amino acids = amino acids that are normally nonessential but become essential under certain conditions nonessential amino acids = group of amino acids that the body can make
distinguish between high-density lipoprotein (HDL) and low-density lipoprotein (LDL)
- High-density lipoprotein (HDL) = lipoprotein that transports cholesterol away from tissues & to the liver, where it can be eliminated; low of this is linked to increased risk of CVD --cholesterol carried by HDL is often called "good" cholesterol b/c it does not contribute to plaque formation - low-density lipoprotein (LDL) = lipoprotein that carries cholesterol into tissues; high of this is linked to increased risk of CVD --cholesterol carried by LDL is often called "bad" cholesterol b/c LDL conveys the lipid tissues, including cells in the arterial walls that make atherosclerotic plaques
summarize current lipid consumption patterns in the USA
-AMDR says the fat is 20 to 35% of total caloric intake -2009-2010 typical Americans consumed about 62 lbs of fat per year -adults should eat more or rich source of polyunsaturated & monounsaturated fatty acids (fish, nuts, & vegetable oils)
explain factors that contribute to celiac disease, and discuss the condition's diagnosis and dietary management
celiac disease = inherited condition in which the protein gluten cannot absorbed; results in damage to the small immune and poor absorption of nutrients (malabsorption) -can be inherited, environmental factors often play a role by triggering the condition -signs & symptoms: abdominal bloating, chronic diarrhea, and weight loss -no cure -good health is followed by gluten-free diet -foods to avoid: barley, rye, triticale, wheat, wheat-enriched flour, durum flour, graham flour, semolina flour, farina, wheat bran, wheat germ, cracked wheat, wheat protein
describe key roles of cholesterol in the body
cholesterol = lipid found in animal foods; precursor for steroid hormones, bile, and vitamin D -most well known sterol -essential to health because its an integral component of every cell membrane in the body -not metabolized for energy, cell use it to synthesize a variety of substances -found only in foods derived from animals (chicken, ice cream, eggs)
describe how complementary protein combinations are used in diet planning
complementary combination = mixing certain plant foods to provide all essential amino acids without adding animal protein plant proteins + grains, seeds, or tree nuts
explain what happens during transamination and deamination
deamination = process of removing of nitrogen-containing group (NH2) from an amino acids transamination = transfer of the nitrogen-containing group from an unneeded amino acid to a carbon skeleton to form an amino acid
identify the two essential fatty acids, & explain their nutritional importance
essential fatty acids = fatty acids that must be supplied by the diet; linoleic and alpha-linolenic acid are essential fatty acids 1- linoleic acid = 18 carbon polyunsaturated fatty acid with two double bonds -- this is omega-6 that converts to arachidonic acid (AA) 2- alpha-linolenic acid = 18 carbon polyunsaturated fatty acid with three double bonds -- this is omega-3 that converts into docosahexaenoic acid (DHA) & eicosapentaenoic acid (EPA)
explain the difference between a food allergy and a food intolerance, and provide examples of each condition
food intolerances = condition characterized by unpleasant physical reactions following consumption of certain foods -not same as food allergy b/c the offending substances in the food does not trigger the body's immune response
describe gallstones and strategies for dietary management
gallstones = hard particles that can accumulate in the gallbladder or become lodged in one of the ducts carrying bile from the gallbladder to the small intestines -consist primarily of cholesterol -remove or damage of gallbladder the person's digests fat less efficiently
identify grains that contain gluten
gluten = type of protein found in many grains; provides texture and shape to baked products -gluten contains peptide gliadin
identify foods that are good sources of high-quality proteins and foods that are sources of low-quality proteins
high-quality (complete) protein = protein that contains all essential amino acids in amounts that support the deposition of protein in tissues and the growth of a young person --egg protein low-quality (incomplete) protein = protein that lacks or has inadequate amounts of one or more of the essential amino acids --meat
lactovegetarian, ovovegetarian, lactoovovegatarian, vegan
lactovegetarian = vegetarian who consumes milk & milk products for animal protein ovovegetarian = vegetarian who eats eggs for animal protein lactoovovegetarian = vegetarian who consumes milk products and eggs for animal protein vegan = vegetarian who east only plant food
identify the function of lipoprotein
lipoprotein serve to transport different forms of fat and cholesterol to areas in the body where they are needed. This transport system is necessary because these types of fats cannot dissolve in the blood.
discuss nitrogen balance
nitrogen balance (equilibrium) = balancing nitrogen intake with nitrogen losses positive nitrogen balance = state in which the body retains more nitrogen than it loses negative nitrogen balance = state in which the body loses more nitrogen than it retains
list at least 6 factors for developing cardiovascular disease
nonmodifiable risk factors -increasing age -male sex -race/ethnic background modifiable risk factors -diabetes mellitus -elevated blood cholesterol -excess body fat -hypertension -physical inactivity -tobaccos use or exposure to tobacco smoke -unhealthy diet -untreated sleep apnea
distinguish between nutrigenomics and nutrigenetics
nutrigenomics = study of how nutrients affect the expression of a person's genome nutrigenetics = the study of how inherited genetic variations influence the body's responses to specific nutrients and nutrient combinations
explain dietary factors that can reduce risk for developing atherosclerosis
omega-3 fatty acids can reduce it to a greater extend than does eating foods that supply omega-6 fatty acids like eating more seafood (fish (tuna & salmon) & shellfish)
explain the cause of phenylketonuria (PKU), and discuss diagnosis and treatment of the disorder
phenylketonuria (PKU) = genetic metabolic disorder characterized by the inability to convert the amino acid phenylalanine into tyrosine, results in accumulation of phenylalanine -rare genetic metabolic disorder -occurs when cells are unable to produce the enzyme phenylalanine hydroxylase or produce an inactive form of the enzyme -phenylalanine hydroxylase converts the essential amino acid phenylalanine into the nonessential amino acid tyrosine
explain how phospholipid differs in structure from a triglyceride
phospholipid = type of lipid needed to make cell membranes & for proper functioning of nerve cells differ? chemically similar to triglyceride except that one of the fatty acids is replaced by a chemical group that contains phosphorus
explain how plants sterols & stanols may lower blood cholesterol levels
plant sterols/stanols = chemicals found in plants that are structurally similar to cholesterol plant sterols and stanols compete wit cholesterol for intestinal absorption, which reduces the amount of cholesterol that is absorbed
compare the primary, secondary, tertiary, and quaternary structures of a protein
primary = refers to the basic structure of protein; a linear chain of amino acids linked by peptide bonds secondary = refers to the coiling of a polypeptide chain tertiary = refers to the 3D structure; twisted structure of a polypeptide chain that includes interactions between various amino acid groups on the chain quaternary = refers to the structure of protein that is comprised of two or more polypeptide chains arranged together in a unique manner
describe protein-energy malnutrition, including differences between marasmus and kwashiorkor
protein-energy malnutrition (PEM) = occurs when the diet lacks sufficient protein and energy marasmus = form of undernutrition that results from starvation; diet lacks energy and nutrients --weakness, wasting, bones showing through skin, weak energy kwashiorkor = form of undernutrition that results from consuming adequate energy and insufficient high-quality protein --women that breastfeed their infants until they give birth to another child
distinguish between saturated, monounsaturated, and polyunsaturated fatty acids
saturated fatty acid (SFA) = fatty acid that has each carbon atom within the chain filled with hydrogen atoms monounsaturated fatty acid (MUFA) = fatty acid that has one double bond within the carbon chains polyunsaturated fatty acid (PUFA) = fatty acid that has two or more double bonds within the carbon chain
describe trans fats, including how they are made and how they are different from most other fats
trans fat = unsaturated fatty acids that have a trans double bond - has at least one trans double bond in their chemical structure, rather than the more common cis configuration
describe the basic structure of triglyceride
triglyceride = lipid that has 3 fatty acids attached to a 3 carbon compound (glycerol)
identify the three major classes of lipids
triglycerides, phospholipids, & sterols (cholesterol) lipids = class of nutrients that do not dissolve in water, but can dissolve in organic solvent (alcohol & acetone)
vegetarians, semivegetarian, pescavegetrian
vegetarians = people who eat plant-based diets semivegetarian ("flexitarian") = a person who usually avoids red meat but consumes other animal foods, including fish, poultry, eggs, and diary products pescavegetrian = vegetarian who consumes fish, milk products, and eggs for animal protein