Final exam
• Esophagus
- A muscular tube that connects the mouth to the stomach. - connects the pharynx to the stomach - Upper esophageal sphincter - relaxes to allow bolus to enter esophagus - lower esophageal sphincter - controls flow into upper stomach
• Normal weight obesity definition
- NWO - you can have a healthy weight but be obese if you have a high percentage of body fat
• Fruits: food examples, general serving size, and typical nutritional content
- food source of: phytochemical, potassium, vitamin C, folate, fiber if unprocessed - low in fat
• Calciferol definition
- form of vitamin D found in both plant and animal foods
• Sterols and stanols definition
- type of lipid that has a more complex structure - cholesterol is the main type of sterol - plant sterols and stanols will compete with cholesterol for absorption, thus decreasing absorption. Found in grains, nuts, fruit, veg...
• Glycogenolysis definition
- when the body needs energy but the cells do not have a direct source of glucose available, the cells can obtain glucose through glycogenolysis - the breakdown of glycogen into glucose - the liver and muscle tissues are the primary sources for glycogen storage - muscle glycogenolysis is only for use by the muscles
• Structure of GI tract
30 foot long tube extending from mouth to anus sphincters: lower esophageal sphincter, pyloric sphincter
• Metabolic water definition
Cells also form some water as a by-product of metabolism; this source is termed metabolic water.
• Hunger, appetite, satiety definitions
Hunger: uncomfortable physiological sensation that drives a person to consume food Appetite: desire to eat appealing food Satiety: the state of being satisfactorily full and unable to take on more
• Fortification of food definition and benefits
The addition of nutrients that are not naturally present to foods - foods selected to be fortified should be those that are commonly consumed and relatively inexpensive so that low-income individuals can afford them (wheat, maize, cereals, vegetable oils, milk)
• Protozoa
single-celled microorganisms that have complex cell structure - example: giardia
• Three steps to energy
• Breaking down triglycerides stored in chylomicrons and adipose cells to mobilize fatty acids • Activate the fatty acids inside cells and transport into mitochondria • Oxidize activated fatty acids into acetyl coA to fuel the citric acid cycle to generate ATP
• How pathogens can get into food
• Cross-contamination definition - poor hygiene - animal contamination - bad storage
• Other ways to estimate total energy expenditure
• Heart rate monitor • Accelerometry • Physical activity questionnaire
• Steps of carbohydrate absorption
• Monosaccharides enter the capillaries of the intestinal villi • Monosaccharides travel to the liver via the portal vein • In the liver, galactose and glucose are converted to fructose
• How the body makes proteins
- the body makes proteins - DNA is the blueprint
• Protein RDA and when it increases
.8g/kg
• Starches
A storage polysaccharide in plants consisting entirely of glucose. - amylose: straight, unbranched glucose polymer - amylopectin: highly branched glucose polymer - come from grains, legumes, vegetables
• Anerobic vs. Aerobic metabolism
Aerobic - ATP production that occurs in the presence of oxygen Anerobic - the metabolic pathway that does not require oxygen
glycogen
An extensively branched glucose storage polysaccharide found in the liver and muscle of animals; the animal equivalent of starch. - Storage form of glucose in the animals body - mostly stored in muscles and liver
• Hydration vs. Dehydration
Hydration: term for the bodies water status Dehydration: body water depletion
• Mechanical vs. Chemical digestion
Mechanical: the physical treatments that food undergoes while in the intestinal tract - think teeth: mastication Chemical: the breakdown of large molecules of food into smaller components, primarily thorough stomach acid and various enzymes.
• Energy yield of macronutrients
Most energy comes from carbohydrates and lipids - less energy comes from proteins - comes from carbohydrates, fat, protein, alcohol - carbohydrates: 4 kcal/g - Fat: 9 kcal/g - Protein: 4 kcal/g - Alcohol: 7 kcal/g vitamins, minerals and water do not provide energy
• Energy expenditures definitions
Total energy expenditure basal metabolism resting metabolic rate Nonexercise activity thermogenesis Thermic effect of food
• What Delaney Clause did
component of the 1958 Food Additive Amendment that prevents manufacturers from adding carcinogenic compounds to foods
• Role of gallbladder
holds bile produced in the liver until it is needed for digesting fatty foods in the duodenum of the small intestine.
• Nutrient requirement definition
smallest amount of a nutrient that maintains a defined level of nutritional health - amount needed to prevent nutrient deficiency disease
• Chemical pathways definition
specific chemical reactions that occur in sequence
• Retinyl esters definition
storage form of vitamin A in the body
• Thermic effect of food definition
the body's speeded-up metabolism in response to having eaten a meal - energy used to digest foods and beverages as well as absorb and further process the macronutrients - TEF
⁃ Metabolism overview
total of all chemical processes that occur in living cells
• Cross-contamination definition
transfer of pathogens from a contaminated food or surface to an uncontaminated food or surface
⁃ Categories
triglycerides, phospholipids, sterols
• Types of non-energy-yielding nutrients
vitamins, minerals and water do not provide energy
• Carotenoids definition
yellow- orange pigments in fruits and vegetables - hundreds exist but only a few including beta-carotine can be converted into biologically active retinoid
• ATP role
(adenosine triphosphate) main energy source that cells use for most of their work - ATP - most energy released by the breakdown of macronutrients is captured in the chemical form of ATP - it is a high energy phosphate compound - when one of the three ATP bonds is broken, it releases energy and becomes adenosine diphosphate (ADP) - can be reformed through phosphorylation, which is an anabolic process - what is left after one of the three bonds in ATP is broken
• Vitamins
- 13 vitamins + vitamin like substances: choline, inositol, carnitine, taurine, lipoic acid - complex organic molecule that regulates certain metabolic processes meets these criteria: - the body cannot synthesize the compound or make enough to maintain good health (it is an essential nutrient) - the compound naturally occurs in commonly eaten foods -signs and symptoms of a health problem (deficiency disorder) eventually occur when the substance is missing from the diet or is not properly metabolized - good health is restored if the deficiency disorder is treated early by supplying the missing substance - NOT metabolized for energy - needed in amounts of milligrams and micrograms
Minerals
- 15 mineral elements have known functions in the body and are necessary for human health. major minerals - essential mineral elements required in amounts of 100 mg or more per day trace minerals trace minerals - essential mineral elements required in amounts that are less than 100 mg per day Compared to plant foods, animal foods tend to be more reliable sources of minerals, such as iron and calcium.
Bolus
- A term used to describe food after it has been chewed and mixed with saliva
• Acceptable macronutrient distribution ranges for each macronutrient
- AMDR - ranges of carbohydrates, fat, and protein intakes that provide adequate amounts of micronutrients and mat recite the risk of diet-related chronic disease - such as type 2 diabetes
• BMI definition
- BMI - numerical value of relationship between body weight and risk of chronic health problems associated with excess body fat calculated by dividing weight in kg by height in meters squared - Limitations of BMI: underweight: <18 healthy: 18.5-24.9 overweight: 25-29.9 obese class one: 30-34.9 obese class two: 35-39.9 obese class three: >40
• Basal metabolic rate • Factors influencing • Calculating
- BMR - measurement of basal metabolism
• Bile salts definition
- Bile salts - a component of bile, aids in lipid digestion
Chloride
- CI- - major minerals - 100 mg or more per day - functions: Maintenance of proper fluid balance • Production of stomach acid • Transmission of nerve impulses • Maintenance of acid-base balance sources: Processed foods, salty snacks, table salt deficiency: Convulsions (observed in infants) toxicity: Hypertension (because of the association with sodium in sodium chloride [table salt])
• Calcium
- Ca - most plentiful in body major minerals - 100 mg or more per day - function: Structural component of bones and teeth • Blood clotting • Transmission of nerve impulses • Muscle contraction • Regulation of metabolism sources: Milk and milk products, canned fish, tofu made with calcium sulfate, leafy vegetables, calcium-fortified foods such as orange juice deficiency: • Increased risk of osteoporosis • May increase risk of hypertension toxicity: may cause kidney stones and interfere with absorption of other minerals.f
• Ergocalciferol definition
- D2 - source of vitamin D found in plant food sources
• Cholecalciferol definition
- D3 - form of vitamin D found in animal food sources
• Components of the digestive system
- Gastrointestinal tract - hollow, muscular tube, ~16 feet - accessory organs - teeth, tongue, salivary glands, liver, gallbladder, pancreas
• Food insecurity in the US
- In 2015, 13% of Americans were food insecure, with approximately 8% living in low food security and 5% living in very low food security. - over 42 million people live in food-insecure households - 29 million adults, 13 million children More likely to be hungry: • Households with children, especially if a single woman is the head of the household; • Households that live at 185% of the poverty threshold; • Hispanic families and black, non-Hispanic families; • Households living in metropolitan areas; and • Households in the southern and western regions of the country, including the states of Alabama, Arkansas, California, Georgia, Mississippi, North Carolina, and Texas.
Potassium
- K - major minerals - 100 mg or more per day - functions: • Maintenance of proper fluid balance • Transmission of nerve impulses • Maintenance of acid-base balance - sources: Fruits, vegetables, milk, meat, legumes, whole grains - deficiency: Irregular heartbeat • Muscle cramps - toxicity: Slowing of heart rate that can result in death
Magnesium
- Mg - major minerals - 100 mg or more per day - functions: • Strengthens bone • Cofactor for certain enzymes • Heart and nerve functioning - sources: Wheat bran, green vegetables, nuts, chocolate, legumes - deficiency: • Muscle weakness and pain • Poor heart function - toxicity: • Diarrhea
• Sodium
- Na - major minerals - 100 mg or more per day - Function: • Maintenance of proper fluid balance • Transmission of nerve impulses • Muscle contraction • Transport of certain substances into cells sources: Table salt; luncheon meats; processed foods; pretzels, chips, and other snack foods; condiments; sauces deficiency: Muscle cramps toxicity: • Contributes to hypertension in susceptible individuals • Increases urinary calcium losses
• Phosphorus
- P - major minerals - 100 mg or more per day - functions: • Structural component of bones and teeth • Maintenance of acid-base balance • Component of DNA, phospholipids, and other organic compounds sources: Dairy products, processed foods, soft drinks, fish, baked goods, meat toxicity: Poor bone mineralization
Sulfer
- S - major minerals - 100 mg or more per day - Deficiency: • Component of organic compounds such as certain amino acids and vitamins - sources: protein rich foods Deficiency: no symptoms Toxicity: unlikely
• Total energy expenditure • Factors influencing • Calculating
- TEE - amount of energy needed for all bodily functions throughout the day
• Upper and lower esophageal sphincters
- Upper esophageal sphincter - relaxes to allow bolus to enter esophagus - lower esophageal sphincter - controls flow into upper stomach
• Triglyceride definition
- a lipid (fat) that has three fatty acids attached to a three-carbon compound called glycerol - 95% of lipids in food and the human body - how the body stores energy as fat - stores more energy than glycogen (from carbs) Adipocytes fat cells, store triglycerides - contain the enzyme hormone sensitive lipase (HSL)
• Phytochemical definition and examples
- a substance found in plant foods that is not an essential nutrient but may have health-promoting properties - such as caffeine and beta-carotene - can be harmful: nicotine, ricin
• Structure and role of large intestine.
- absorbs water / starts to solidify waste - no villi but some minor absorption - goblet cells secrete mucous - cecum is the first section, rectum the last section - external anal sphincter allows feces to be expelled from the anus
E
- alpha-tocopheral, other tocopherols - fat-soluble - antioxidant - the natural form is more biologically active than the synthetic major function in body: antioxidant major dietary sources: vegetable oils, certain fruit and veg, nuts, seeds, fortified cereals Major signs of deficiency: loss of muscular coordination, retinal damage, hemolysis of red blood cells resulting in anemia major signs of toxicity: excessive bleeding due to interfering with vit K metabolism RDA for vitamin E is 15 mg/day
• Genetic modification definition
- altering an organism's genetic material in an effort to create a new organism with different traits; also called genetic engineering
⁃ Antioxidants
- an atom or molecule that loses one or more electrons has been oxidized - vitamin E - cells regulate oxidation reactions be using antioxidants - antioxidants protect cells by giving up electrons to free radicals, which stabilizes the oxidant
Solid fats
- beef fat, butter, stick margarin, lard (pork fat), shortening, whipped cream, cream cheese, coconut oil - generally considered unhealthy - associated with an increased risk in cardiovascular disease (CVD)
⁃ Protein digestion
- begins in stomach - Hydrochloric acid (HCI) denatures proteins and activates pepsin, an enzyme that breaks down proteins into smaller polypeptides in stomach - in SI, trypsin and chymotrypsin break down polypeptides into peptides and amino acids
• Ways to measure protein quality
- biological value (BV) - measure of quality based on how quickly it can be turned into body tissue Protein digestibility corrected amino acid score (PDCAAS) - measure of quality based on ability of protein to support weight gain in a lab animal
• The body's response to an overnight fast or starvation
- blood glucose levels fall - pancreas releases glucagon - glucagon tells liver cells to increase glycogenolysis which maintain blood glucose levels - when livers supply of glycogen is gone, glucagon stimulates liver cells to convert amino acids derived from muscle tissue to pyruvate and then glucose through gluconeogenesis Starvation: - liver and muscle glycogen are depleted - cells use fatty acids for energy - adipose tissue increases lipolysis increasing fatty acids in the blood stream - when fatty acids become too much for the liver to handle, the liver resorts to ketogenesis to convert CoA into ketone bodies that can be used as an alternative energy source
• Resting metabolic rate
- body's rate of energy use a few hours after eating and resting - impacted by: body composition, sex, surface area, age, thyroid hormone, caloric intake, drugs, stress...
• Major functions of protein in the body; know specifics of
- build cells and parts of body - component of hardened structures in hair and nails - enzymes - lubricants - clotting compounds - build antibodies - maintain pH balance - transporters - make some hormones - energy source under bad conditions
• Empty calorie definition and examples
- calories from unhealthy solid fats and added sugars -A popular term referring to foods that contribute much energy but too little of the nutrients
Macronutrients
- carbohydrates, proteins, lipids - nutrients that the body needs in large amounts
D
- cholecalciferol, ergocalciferol - fat-soluble - acts as hormone - not an essential nutrient major functions; absorption of calcium and phosphorus, maintenance of normal blood calcium, calcification of bone, maintenance of immune function sources: vit-D fortified milk, fortified cereal, fish liver oils, fatty fish biggest source: sunlight Plant form: D2 - calcifreol Animal and sun: D3 - ergocalciferol major deficiency signs: rickets in children, ostomalacia in adults, soft bones, depressed growth, reduced immune system functioning major signs of toxicity; poor growth, calcium deposits in soft tissue RDA for vitamin D is 15 μg/day
• How to make a protein complete
- complete: contain all essential amino acids in the amounts that support deposition of protein in tissues and growth, animal products - incomplete: lacks or does not have enough essential amino acids -- can be made up for by selecting complementary proteins -- limiting amino acids is the one there is not enough of
• Peristalsis definition
- coordinated waves of muscular contractions that help move food through most of the GI tract
⁃ Food labels
- country of origin - ingredients (order by weight) - amount of product - Nutritional fact panel with Daily Values (DV) -- required: total fat, cholesterol, sodium, total carbohydrate, fiber, total sugar, added sugar, protein, vitamin D, potassium, calcium, iron - serving size is set by company
Nutrient dense
- describes a food that supplies more key beneficial nutrients and less solid fats, added sugar, refined starches, and sodium
• Calorie dense vs. Energy dense foods
- describes a food that supplies more key beneficial nutrients and less solid fats, added sugar, refined starches, and sodium - refers to the amount of energy a food provides per given weight of the food
• Food desert definition
- deserts regions or areas in which a large proportion of those living there experience difficulty in obtaining nutritious food - with numerous low-income people living farther than 0.5 miles away from grocery stores in urban areas or farther than 10 miles away from grocery stores in rural areas.
• Role of chewing
- digestion begins in the mouth - chewing begins mechanical digestion
• Mouth
- digestion begins in the mouth - chewing begins mechanical digestion - enzymes in saliva begin chemical digestion
⁃ Blood glucose regulation
- done through insulin and glucagon
Iodine deficiency
- essential for metabolism and thyroid function - deficiency: goiter, during pregnancy can result in intellectual disabilities in the developing fetus (cretinism) - The average intelligence quotient, or IQ score, is as much as 13 points higher in countries with populations that have adequate dietary iodine status versus countries with populations that experience widespread deficiencies of the mineral. - present in dairy and seafood, fortified salt
• Role and examples of sphincters
- external anal sphincter allows feces to be expelled from the anus - food leaves stomach through the pyloric sphincter - lower esophageal sphincter, pyloric sphincter
• What happens to extra amino acids
- extra amino acids undergo deamination
• Essential fatty acids
- fatty acids that must be supplied by the diet - linoleic (omega6), used to make AA - alpha-linolenic (omega3), used to make DHA and EPA
• Primary, secondary, tertiary, quaternary structure definition
- first a chain of amino acids - then a coil - then the coils are folded - then two or more are arranged together
• Basic protein structure
- first a chain of amino acids, then a coil, then the coils are folded, then two or more are arranged together - Proteins that fold improperly may also impact the health of the cell regardless of the function of the protein. When proteins fail to fold into their functional state, the resulting misfolded proteins can be contorted into shapes that are unfavorable to the crowded cellular environment.
• Dietary guidance system goals
- food guide that translates the DRIs and evidence based information concerning the effect of certain foods and food components on health into dietary recommendations - food guide - 'practical' guideline
• Pyloric sphincter
- food leaves stomach through the pyloric sphincter
• Determining if a grain is whole
- foods made with the entire grain - bran, germ and endosperm - milling removes bran and germ which reduces protein, fiber, vitamins and minerals Bran: fiber, vitamin B, minerals, protein Germ: minerals, vitamin b, vitamin e, other phytochemicals Endosperm: carbohydrates, proteins, and vitamin b
• Whole grains
- foods made with the entire grain - bran, germ and endosperm - milling removes bran and germ which reduces protein, fiber, vitamins and minerals Bran: fiber, vitamin B, minerals, protein Germ: minerals, vitamin b, vitamin e, other phytochemicals Endosperm: carbohydrates, proteins, and vitamin b
• Role of genes in weight loss
- genetic factors: thrift genes: genetic predisposal for a conservative metabolism set points: scientific notion that the body's fat content and body weight is genetically predetermined
• Vegetables: food examples, general serving size, and typical nutritional content
- good source of: potassium, vitamins A and C, folate, fiber, phytochemical - low in fat - can be recommended in food guides in groups: dark green leafy vegetables, starchy, orange - sometimes includes dried beans and pease
⁃ Major food groups
- grains, diary, fruits, vegetables, protein rich foods (not oils) - nutrient content of foods within the same food group can vary widely
• Complex carbohydrates
- have three of more monosaccharides bonded together - oligosaccharides - from 3-10 monosaccharides bonded together. -- raffinose: nondigestable -- stachyose - nondigestable - polysaccharides - ten or more monosaccharides bonded together
• Disaccharides • What monosaccharide each example is made up of
- have two saccharides - formed through a condensation reaction where the two molecules were bonded and water was released Maltose: - malt sugar - glucose+glucose Sucrose: - table sugar - glucose+fructose Lactose: - milk sugar - glucose+galactose
Heme iron vs non heme iron
- heme - iron-containing component of hemoglobin and myoglobin - heme iron: form of iron found in meat that is absorbed efficiently non heme: - form of iron that is not absorbed as efficiently as heme iron; found in meat, vegetables, grains, supplements, and fortified or enriched foods
• Leptin
- hormone secreted by adipose tissue that reduces hunger
• Amylin
- hormone secreted by the pancreases that slows gastric emptying and reduces hunger
• Ghrelin
- hormone secreted by the stomach and other tissue that stimulates eating
• How fatty acids are identified
- identified by number of carbon atoms and bond between carbon atoms
Vitamin A deficiency
- important for immunity, vision, reproduction, cell growth - leading cause of night blindness and xerophthalmia - drying of eye surfaces including the conjunctiva; also known as dry eye - can be addressed through twice a year supplementation - golden rice biofortified with vitamin A
• MyPlate recommendations
- includes a variety of food, nutrition and physical activity resources - based on 2015-2020 Dietary Guidelines for America - no longer has six food groups (no oil) - based on a 2000 calorie diet
• Oils: food examples, general serving size, and typical nutritional content
- includes liquid oils: canola, olive, corn... good source of: vitamin E and essential fatty acids, - USDA does not classify oils as a separate food group - one serving = one tablespoon
• Whole grain
- intact, ground, cracked, or flacked seeds of cereal grains
• Biotechnology definition
- involves the use of living things—plants, animals, and microbes— to manufacture new products. Biotechnology in agriculture can include the use of both traditional practices, such as cross-breeding of plants and animals, and progressive practices, such as the alteration of genes. - use of living things to produce new products - Genetic modification - new crops that supply higher yields, resist pests and diseases, drought tolerant, can handle temperature extremes, nutritionally enhanced - can be modified to be resistant to a certain herbicide, which leads to higher herbicide use
• Functions of water
- is a major solvent for substances like glucose - Water helps transport water-soluble substances within and outside cells.
• What proteins are
- large complex organic molecules made up of amino acids - contain: carbon, hydrogen, oxygen, nitrogen
• What happens on the electron transport chain?
- linked series of enzymes that synthesize water and ATP during aerobic metabolism
• Role of lipases
- lipases - an enzyme that breaks down lipids
• Hyponatremia definition and causes
- low blood sodium - excess water dilutes the sodium concentration of blood, disrupting water balance
• Trans fats
- made by partial hydrogenation, the process that adds hydrogen atoms to liquid vegetable oil - can be stored for longer and less likely to oxidize - raises "bad" cholesterol levels in blood - increases risk of heart disease - banned in the US
• Role of liver
- makes bile-mixture of cholesterol, minerals, bile salts, bilirubin used in fat digestion
• Calorie definition
- measure of energy calorie: Amount of energy needed to raise temperature 1 gram of water 1 degree C Calorie (kilocalorie=kcal) : Amount of energy needed to raise temperature 1000 gram (liter) of water 1 degree C - bomb calorimeter: device used to measure the calories in a sample of food
• Basal metabolism • Factors influencing • Calculating
- measured with BMR - minimum number of calories the body uses for vital physiological activities after fasting and resting for 12 hours
• Body composition definition
- measurement of body tissues, usually expressed as percent body fat
• Protein: food examples, general serving size, and typical nutritional content
- meat, beans, eggs, nuts, tofu, seeds - good sources of: iron, zinc, and B vitamins - iron and zinc are more easily absorbed from animal foods than from plants
• Two-component model
- method of measuring body composition that divides the body into two compartments: fat mass and fat-free mass
• Dairy: food examples, general serving size, and typical nutritional content
- milk and milk products - good source of protein, phosphorus (mineral), riboflavin (B vitamin) Can be a good source of vitamins A and D if fortified
• Role of saliva, salivary glands
- mix of water and mucous that softens food for easier swallowing - contains enzymes that begin chemical digestion - comes from salivary glands - three main enzymes: 1. lysozyme: destroys some bacteria 2. Salivary amylase: begins to break down starch 3. Lingual lipase: inactive until it reaches the stomach where it is activated by the stomach acid, begins fat digestion
• Role of large intestine in fiber digestion
- most fiber passes through to the LI where bacterial enzymes break it down
• Wall of GI tract
- mucosa: secretes mucus - Lumen: hollow space - longitudinal muscle - circular muscle
• Amino acids
- nitrogen containing chemical units that make up proteins - 20 different ones - peptide bond: links two amino acids together
• Understand general under-5 mortality statistics
- number of newborns in a population, per 100 live births, who are likely to die before they reach give years of age
• What a nutrition facts panel includes
- nutrition information about a food's nutrient contents that is deployed in a specific format on the food's package -- required: total fat, cholesterol, sodium, total carbohydrate, fiber, total sugar, added sugar, protein, vitamin D, potassium, calcium, iron - serving size is set by company
• What carbohydrates are
- one of the six classes of nutrients - major course of energy - serve as the glue that holds cells together - can be 'simple' or 'complex' - plants are a rich source of carbohydrates - made using the sun's energy to combine carbon, oxygen, and hydrogen from carbon dioxide
amino acid metabolism
- only done after the need for amino acids to synthesize essential proteins and enzymes, structural molecules and hormones are met - remaining amino acids can be catabolized for ATP - nitrogen group of amino acid must be removed by deamination or transamination - requires a coenzyme - then the carbon chain enters the citric acid cycle as either a glycogenic or ketogenic amino acid - excess amino acids: are stripped of their nitrogen group and used to make glucose or fat
• Mitochondria role
- organelles that synthesize most of the ATP that cells need to function - catabolizes macronutrients and transfers the released energy into ATP
• Glycogenesis definition
- pathway that enables certain cells to store glucose and glycogen - liver and muscle cells can do this to store glucose as glycogen when it is not needed
K
- phylloquinones, menaquinones - fat-soluble - bacteria in the lower intestinal tract produce vitamin K major function: production of active blood-clotting factors Major dietary sources: egg yolk, butter, beef, fermented foods Major signs of deficiency: excessive bleeding Major signs of toxicity: unknown No RDAs for vitamin K have been established
• Enterohepatic circulation role
- process that recycles bile salts in the body - plants containing soluble fiber interfere with cholesterol and bile absorption
• Dietary supplement definition
- products containing vitamin, mineral or herbs, amino acids or other dietary supplement - are NOT rigorously tested
• Peptide YY
- protein hormone that signals the stomach to reduce ghrelin secretion
⁃ Dietary guidelines for Americans
- put together by USDHS and USDA every five years - Officials serve on Dietary Guidelines Advisory Committee (DGAC) - a healthy diet contains more fruits, vegetables, whole grains, low or non fat dairy, seafood, legumes, nuts than the typical american diet currently contains Recommendations: - cholesterol intake should be as low as possible - limit alcohol (1/2 per day) - Limit caffeine (400 mg/day) - focus on variety of nutrient dense foods - choose whole fruits (at least half) - choose whole grains (at least half) - limit calories from added sugar and saturated fats (less than 10%) - reduce sodium intake (less than 2300mg) - choose low fait dairy - consume at least 8oz of seafood a week - replace solid fats with liquid oils - nutrients of public health concern: potassium, dietary fiber, calcium, vitamin D (iron for pregnant women)
Major functions of vitamins
- regulation of body process - immune function - production and maintenance of cells - protection against agents that can damage cellular components - Major elements: carbon, hydrogen, oxygen, nitrogen, sulfur, phosphorus, cobalt - organic
Major functions of minerals
- regulation of body processes, including fluid balance and energy metabolism - formation of certain chemical messengers - formation of structural and functional components of various substances and tissues - Cellular development, growth, maintenance - Major elements: all the minerals... - inorganic - usually have narrow ranges of safe intakes
• Weight cycling definition
- repeated bouts of losing and gaining significant amounts of weight
• Role of salivary amylase
- salivary amylase secreted by the salivary glands begins to break down starch in mouth
• Role of the mouth
- salivary amylase secreted by the salivary glands begins to break down starch in mouth - mechanical digestion by chewing
Carbohydrate digestion, absorption, and transport
- salivary amylase secreted by the salivary glands begins to break down starch in mouth - not digested in stomach - digested in SI - most fiber passes through to the LI where bacterial enzymes break it down - absorbed through active transport, which requires a carrier cell and energy, and diffusion which requires a carrier cell but no energy - fiber in food delays how quickly chyme empties from stomach, which promotes satiety - broken down by pancreatic amylase in SI - Maltase enzyme digests maltose - sucrase enzyme splits sucrose
• Daily values: definition, what they are based on, what they are established for
- set of nutrient intake standards developed for labeling purposes - developed based on RDAs - based on 2000 calorie diet - mostly you want to meet 100%, except for harmful foods such as saturated fat and sodium - low source: <5% - high source: >20%
• Adequate intake definition and uses
- set when there is not enough information to develop an RDA - used as a nutrient intake goal - developed by looking at the average daily intake of a group of healthy individuals, if they no indication of deficiency, their intake is assumed to be adequate - examples: fiber, sodium, water, potassium...
• Monosaccharaides
- simple sugar that is the basic molecule of carbohydrates have one saccharide - glucose, fructose, galactose Glucose: - primary fuel for muscles and cells - also called blood sugar Fructose: - fruit sugar, body converts into glucose Galactose: - a component of lactose that is not commonly found in foods
• Peptide and polypeptide definition
- small chain of two or more amino acids - polypeptides - proteins made of 50 or more amino acids - peptide bond: links two amino acids together
• Recommended dietary allowances definition and uses
- standards for recommended daily intakes of several nutrients - Meet the needs of of 97-98% of healthy individuals in a particular life stage/age/sex group - RDAs are determined by adding a margin of safety to the EAR
• Malnutrition definition
- state of health that occurs when the body is improperly nourished - can be over-nutrition and undernutrition - Causes: lack of knowledge, low income, eating disorders, addiction, medical problems... - availability, accessibility, affordability, utilization
• Denaturation definition and when it occurs
- straightening out of proteins - permanently alters shape
• Free radical definition
- substance with an unpaired electron - an oxidation reaction can form a free radical, a substance with an unpaired electron - highly reactive, chemically unstable - they remove remove electrons from more stable molecules like proteins, fatty acids, and DNA -- damages or destroys them
• Multivitamin-multimineral supplement definition
- supplements containing two or more vitamins and mineral
• Skinfold thickness measurements
- technique of estimating body composition in which calipers are used to measure the thickness of skinfolds at multiple body sites
• Phosphorylation definition
- the anabolic reaction that results in the attachment of a Pi group to ADP to make ATP
• What occurs in the citric acid cycle (just focus on the text on the slides, rather than the diagrams)
- the complex series of chemical reactions that are involved in energy metabolism - converts the two carbon CoA into CO2 and H2O - the energy that is released is captured as ATP Major steps: 1. CoA binds with oxaloacetate to form citrate 2. citrate is converted into intermediates and then alpha-ketoglutarate 3. alpha-ketoglutarate oxidizes and forms succunyl-CoA 4. ATP is starts being formed 5. The cycle repeats
⁃ Fatty acid metabolism
- the enzyme hormone sensitive lipase (HSL) removes the three fatty acids from the triglyceride carbon backbone - the glycerol and fatty acids enter the bloodstream - the fatty acid can be used as energy - the glycerol is turned into pyruvate or or glucose in the liver, but this is low energy
⁃ Bioavailability
- the extent to which the digestive tract absorbs a nutrient and how well the body uses it - impacted by: food processing and preparation, digestion, absorption - changes in GI tract transit time - health conditions - processing and preparation - source of vitamin - most often highest in natural sources, but not always (folate is exception)
Role of epiglottis
- the flap of tough tissue that prevents food from entering the larynx and trachea
Glucose
- the form of sugar that circulates in the blood and provides the major source of energy for body tissues. - cells metabolize glucose to release the energy stored in the molecule
• Gluconeogenesis definition and examples
- the synthesis of glucose from noncarbohydrate sources (glycerol, lactate, pyruvate, amino acids) - in liver
• Muscle layers of the stomach
- the wall of the stomach is the thickest and strongest of the GI tract - the stomach has both longitudinal muscle and circular muscle like the GI tract, as well as diagonal muscles (obliques) - gastric juice mixes with food to form chyme - food leaves stomach through the pyloric sphincter - empties about four hours after meal
• What happens to pyruvate with plenty of oxygen is available? • What happens without oxygen
- three-carbon molecule that results from the breakdown of glucose during glycolysis - used in two ways, 1. if there is oxygen =, it is turned into CoA 2. if there is not oxygen it is turned into lactic acid, which is turned into glucose in the liver
⁃ Consumption
- total fat: 20-35% of calories - saturated fate: less than 10% - transfat: as little as possible - Linoleic acid: 1-15% - alpha linoleic acid: .6-1.2% cholesterol: as little as possible while consuming a healthy diet
Chromium
- trace mineral, less than 100mg per day - Cr Functions: Enhances insulin action - sources: Egg yolks, whole grains, pork, nuts, mushrooms - deficiency: Blood glucose level remains elevated after meals - toxicity: Unknown but currently under scientific investigation • May interact with certain medications
Copper
- trace mineral, less than 100mg per day - Cu Functions: Promotes iron metabolism • Component of antioxidant enzymes • Component of enzymes involved in connective tissue synthesis sources: Liver, cocoa, legumes, whole grains, deficiency: Anemia • Reduced immune system function • Poor growth and development toxicity: • Vomiting • Abnormal nervous system function • Liver damage
Fluoride
- trace mineral, less than 100mg per day - F- - functions: Increases resistance of tooth enamel to cavity formation • Stimulates bone formation - sources: Fluoridated water, tea, seaweed - Deficiency: No true deficiency, but increased risk of tooth decay - Toxicity: Stomach upset • Staining of teeth during development • Bone deterioration
iron deficiency
- trace mineral, less than 100mg per day - Fe - heme and nonheme - functions: • Component of hemoglobin and myoglobin that carries oxygen • Energy generation • Immune system function sources: Meat and other animal foods, except milk; whole-grain and enriched breads and cereals; fortified cereals deficiency: • Fatigue upon exertion • Small, pale red blood cells • Low hemoglobin levels • Poor immune system function • Growth and developmental retardation in infants toxicity: • Intestinal upset • Organ damage • Death - most prevalent micronutrient deficiency in the world - needed for hemoglobin development, oxygen delivery to the brain and muscles - pregnancy increases need to build placenta and fetus - iron rich foods include: red meats, dark green leafy vegetables, fortified cereal grains - Women with iron-deficiency anemia are at greater risk for serious complications during childbirth, including hemorrhage, or uncontrolled bleeding, which can be deadly. According to health experts, maternal mortality rates could be decreased significantly with appropriate iron supplementation during pregnancy.
Iodine
- trace mineral, less than 100mg per day - I - Functions: Component of thyroid hormones sources: Iodized salt, saltwater fish, dairy products Deficiency: • Goiter • Cretinism (intellectual impairment and poor growth in infants of women who were iodine deficient during pregnancy) Toxicity: Reduced thyroid gland function
manganese
- trace mineral, less than 100mg per day - Mn
molybdenum
- trace mineral, less than 100mg per day - Mo - function: Cofactor for certain enzymes, including some involved in carbohydrate metabolism - sources: Liver, peas, beans, cereal products, leafy vegetables, low-fat milk deficiency: None in healthy humans toxicity: • Rarely occurs from usual dietary sources • Overdoses of dietary supplements containing molybdenum may cause joint pain and swelling of feet or lower legs.
Selenium
- trace mineral, less than 100mg per day - Se - functions: Component of an antioxidant system - sources: Meat, eggs, fish, seafood, whole grains - deficiency: Muscle pain and weakness • Form of heart disease toxicity: • Nausea • Vomiting • Hair loss • Weakness • Liver damage
Zinc deficiency
- trace mineral, less than 100mg per day - Zn - Functions: Component of numerous enzymes - sources: Seafood, meat, whole grains deficiency: Skin rash • Diarrhea • Depressed sense of taste and smell • Hair loss • Poor growth and physical development Toxicity: • Intestinal upset • Depressed immune system function • Supplement use can reduce copper absorption. - important for immunity, sexual maturation in adolescents - fetus has high demand for zinc - zinc supplements help with diarrhea - found in animal foods, and grains (though grains also contain phytic acid that limits absorption)
• Fiber
- two kinds: soluble and insoluble - only provided by plant foods Adequate intake (AI) - women: 25g/day - men: 38 g/day * typical American diet supplies ~17g/day soluble: delays stomach emptying and slows glucose absorption, can lower blood sugar insoluble: increases fecal bulk, speeds passage through GI tract
Micronutrients
- vitamins and minerals - nutrients that the body needs in very small amounts
• Role of pancreas
-produces pancreatic juices to digest food, and produces insulin into bloodstream to regulate metabolism - secretes bicarbonate ions to increase pH of chyme - enzymes to digest carbs, proteins, fats Pancreas: Pancreatic amylase - digests starch pancreatic lipase - digests fat trypsin, chymotripsin - partially digests proteins
Carbohydrate catabolism
1. Glycolysis - the first phase of glucose catabolism, the 6 carbon glucose molecule is broken down into two three carob molecules of pyruvate - then pyruvate is turned into CoA if there is oxygen or lactic acid if there is not 2. citric acid cycle - the two CoA undergo conversion, results in NADH, FADH2, (NAD+, FAD) CO2 and ATP 3. Electric transport chain - NADH, FADH2 release energy in mitochondria
⁃ Carbohydrate metabolism
1. Glycolysis - the first phase of glucose catabolism, the 6 carbon glucose molecule is broken down into two three carob molecules of pyruvate - then pyruvate is turned into CoA if there is oxygen or lactic acid if there is not 2. citric acid cycle - the two CoA undergo conversion, results in NADH, FADH2, (NAD+, FAD) CO2 and ATP 3. Electric transport chain - NADH, FADH2 release energy in mitochondria
• Secretions of the stomach, their cells, and their functions
1. mucous gland: mucus - protects stomach 2. Parietal gland: components that form HCI - activates pepsinogen and destroys food born microbes. intrinsic factor - facilitates b12 absorption 3. Chief gland: pepsinogen - digests protein after conversion to pepsin by HCI gastric lipase - digests small amount of fat 4. G cell gland: gastrin - stimulates stomach motility and gastric gland activity
• Checking temperature
40-140 degreed f
⁃ Fat-soluble vitamins
A D E K - can be stored - found in the lipid portions of foods and tend to be associated with lipids in the body - digested and absorbed with lipids in the body in the GI tract - - foods rich in fat often contain the fat-soluble vitamins (A, D, E, K)
• Definition of a nutrient
A chemical found in food that helps the body maintain itself- provides energy, structural materials, and regulating agents to support growth, maintenance, and repair of body tissues
• Role of hypothalamus
A neural structure lying below the thalamus; it directs several maintenance activities (eating, drinking, body temperature), helps govern the endocrine system via the pituitary gland, and is linked to emotion and reward.
Dietary Reference Intakes (DRIs)
A set of nutritional reference values for the United States and Canada that applies to healthy people. - can be used as references when making dietary recommendations standards include: - Estimated Average Requirement - Recommended Daily Allowances - Adequate intake - Tolerable Upper Intake Level - Acceptable Macronutrient Distribution Range
Type 2 diabetes
A syndrome marked by the presence of usually three or more of a group of factors (as high blood pressure, abdominal obesity, high triglyceride levels, low HDL levels, and high fasting levels of blood sugar) that are linked to increased risk of cardiovascular disease and Type 2 diabetes.
• Markers for metabolic syndrome
A syndrome marked by the presence of usually three or more of a group of factors (as high blood pressure, abdominal obesity, high triglyceride levels, low HDL levels, and high fasting levels of blood sugar) that are linked to increased risk of cardiovascular disease and Type 2 diabetes.
• Roles of enzymes and coenzymes
An organic molecule that is a necessary participant in some enzymatic reactions; helps catalysis by donating or accepting electrons or functional groups; e.g., a vitamin, ATP, NAD+. - examples: - nicotinamide adenine dinucleotide (NAD+) - flavin adenine dinucleotide )FAD)
Definitions of digestion
Breakdown of food substances into simpler forms that can be absorbed and used
• Short vs. Medium vs. Long chain fatty acids
Building blocks of Lipids - identified by number of carbon atoms and bond between carbon atoms Types: saturated, monounsaturated, polyunsaturated - structure: hydrocarbon chain, omega group on one end, acid group on other end - Short chain fatty acids (2-4 carbons), medium chain (6-12), long chain (14-24)
• Know generally which minerals are most common in the body
Calcium Phosphorus
• Major functions of macronutrients
Carbohydrate: major source of energy - maintenance of normal blood glucose levels - elimination of solid waste from gastrointestinal tract (fiber) - Major elements: carbon, hydrogen, oxygen - organic Lipids: - Major source of energy (fat) - cellular development, physical growth and development - regulation of body processes (certain hormones for example) - growth and development of brain - absorption of fat-soluble vitamins - Major elements: all have carbon, hydrogen and oxygen, some have phosphorus, nitrogen - organic Protein: - production of structural components, such as cell membranes and functional components, such as enzymes - cellular development, growth, maintenance - regulation of body process (certain hormones for example) - a minor source of energy - Major elements: carbon, hydrogen, oxygen, nitrogen, sulfur - organic
Nutrients
Carbohydrates, lipids, proteins, vitamins, minerals, water - 6 groups - sources of elements needed by the body to carry out its activities
• Conditionally essential nutrients
Conditionally essential nutrients: A nutrient can be essential only under specific circumstances: pregnancy, metabolic disorders, serious illness
• Cortisol and epinephrine roles
Cortisol: - catabolic - increases glycogenolysis and gluconeogenesis - increases lipolysis Epinephrin: - catabolic - increases glycogenolysis and gluconeogenesis - increases lipolysis
⁃ Digestion, absorption, and transport of lipids
Digestion: - lipases - an enzyme that breaks down lipids - pancreatic lipase - the digestive enzyme that removes two fatty acids from each triglyceride molecule - Bile salts - a component of bile, aids in lipid digestion Absorption - long chain fatty acids, bile, cholesterol, fat soluble vitamins pack together to make micelles - micelles are then absorbed and bile salts left behind Transport:
• Micelle role
During lipid absorption: - long chain fatty acids, bile, cholesterol, fat soluble vitamins pack together to make micelles - micelles are then absorbed and bile salts left behind
• Lipids definition
Energy-rich organic compounds, such as fats, oils, and waxes, that are made of carbon, hydrogen, and oxygen. - Do not dissolve in water triglycerides, phospholipids, sterols
• Enrichment vs. Fortification
Enrichment: - replacement of some nutrients that were removed during processing - the addition of specific amounts of iron and the B vitamins thiamin, riboflavin, niacin, and folic acid to refined grain products such as wheat flour and white rice Fortification: - addition of nutrients to any food to boost its nutritional value - common: vitamin A or D to milk, calcium to orange juice
Estimated average requirement
Estimated amount of a nutrient per day at which the needs of 50% of a specific population will be met - categorizes people based on life stage, pregnant or not, and gender - develops by identifying a physiological marker that reflects proper body functioning which can indicate if the level in the body is adequate
• Role of villi and enterocytes
Fingerlike extensions of the intestinal mucosa that increase the surface area for absorption - enterocytes: absorptive cells that form the outer layer of a villus. covered in microvilli. - core of the villus contains: arteriole, capillary network, venule, lacteal (lymph system) - enterocytes: absorptive cells that form the outer layer of a villus. covered in microvilli. - remove nutrients from chyme and enable them to enter the intestinal blood or lymph vessels
• Generally Recognized as Safe definition
GRAS - ingredients thought to be safe when used for intended purposes, but that are not thoroughly tested - is a United States Food and Drug Administration (FDA) designation that a chemical or substance added to food is considered safe by experts, and so is exempted from the usual Federal Food, Drug, and Cosmetic Act (FFDCA) food additive tolerance requirements.
• Glycemic index and glycemic load definitions
Index: a method of classifying foods according to their potential for raising blood glucose load: - the amount of carbohydrate in a food multiplied by the glycemic index of the carbohydrate - a tool to measure the body's insulin response to a carbohydrate containing food, similar to the GI but takes into consideration the serving size
• Insulin and glucagon roles
Insalin: A protein hormone synthesized in the pancreas that regulates blood sugar levels by facilitating the uptake of glucose into tissues Glucagon: produced by alpha cells in pancreas; increases blood glucose levels by promoting gluconeogenesis and glycogenolysis in the liver
• Insulin vs. Glucagon roles
Insulin: - anabolic - increases glycolysus and glycogenesis - increases lipogenesis - increases glucose uptake Glucagon: - catabolic - increases glycogenolysis and gluconeogenesis
• Energy intake and output definitions
Intake: calories from foods and beverages that contain macronutrients and alcohol Output: calories cells use to carry out activities
• Intracellular vs. Extracellular water
Intracellular: water that is inside cells - About two-thirds of the body's water is in the intracellular compartment. Extracellular: water that is inside cells - About two-thirds of the body's water is in the intracellular compartment.
• Benefits and drawbacks of irradiation
Ionizing radiation applied to food to kill microorganisms and other pests. Ionizing radiation disrupts the internal molecular workings of cells, killing them.
Major function of water
Maintenance of fluid balance, regulation of body temperature, elimination of wastes, transportation of substances, participant in many chemical reactions - maintenance of fluid balance - regulation of body temperature - elimination of waste - transportation of substances - participation in many chemical reactions - Major elements: hydrogen, oxygen - inorganic
• Major vs. Trace minerals and examples of each
Major: calcium chloride magnesium phosphorus potassium sodium sulfer Trace: chromium fluoride copper iodine iron manganese molybdenum selenium zinc Possible trace: arsenic boron lithium nickel silicon vanadium
• Examples of B vitamins and their coenzymes
Many of the chemical reactions involved in the metabolism of carbohydrates, fats, and amino acids involve coenzymes that contain B vitamins. B vitamins (see Chapter 8). The coenzyme forms of B vitamins are often found in foods; this form of the vitamin undergoes digestion to release the free form of the vitamin. Following absorption, cells combine one of the B vitamins with a nitrogen-containing, nonprotein compound, to synthesize a coenzyme (Fig. 10.2). Upon activation by the coenzyme, the enzyme enables the reaction to occur. - if the diet does not include enough B vitamins, which are components of coenzymes, the cells will be unable to synthesize the coenzymes needed for catabolism - this will lead to a lack of energy, weakness...
• Types of protein-energy malnutrition
Marasmic Kwashiorkor- combination of chronic energy deficit and chronic or acute protein deficiency - stunted, blonde brittle hair, pale skin, swollen limbs
• Know generally what the most common pathogens in the US are
Norovirus: - food-borne pathogen - severe vomiting, diarrhea, cramps - most common in the US Rotavirus: -food-borne pathogen - diarrhea, vomiting, fever
⁃ Common food-borne pathogens
Norovirus: - food-borne pathogen - severe vomiting, diarrhea, cramps - most common in the US Rotavirus: -food-borne pathogen - diarrhea, vomiting, fever
• Essential nutrient definition
Nutrients that mist be supplies by food because the body does not synthesize the nutrient or make enough to meet its needs water: water carbs: glucose Lipids: fats containing linoleic acid Vitamins: A, Thiamin, riboflavin, niacin, pantothenic acid, biotin, folate, B-6, B-12, C, K, E, D, choline Minerals: some major and trace minerals A nutrient is essential if: 1. a deficiency disease results from it missing 2. when added back the disease goes away 3. there is an explanation about why the abnormalities occur when the substance is missing Conditionally essential nutrients: A nutrient can be essential only under specific circumstances: pregnancy, metabolic disorders, serious illness
• Definition of nutrient science
Nutritional science deals with the organism's responses to the diet. It includes studies not only on the nutrients themselves but also on molecular interactions, metabolic and signaling pathways, physiology, pathology, and toxicology.
• Overweight and obesity definitions and consequences
Overweight: has extra body weight that is contributed by bone, muscle, body fat and/or water - so, overweight can be all muscle Obesity: - excessive body fat Causes: - type 2 diabetes - coronary artery disease - stroke - certain cancers - social stigma - psychological damage - gout -gallbladder - infertility - ...
• Food security vs. Food insecurity
Security: - state in which individuals have access to enough food at all times ot lead a healthy, active life Insecurity: - state in which individuals are concerned about running out of food of not having enough money to buy more food
Classification of carbohydrates
Simple or complex simple - monosaccharides: glucose, fructose, galactose - disaccharides: maltose, lactose, sucrose * each gram supplies 4 kcal complex: - oligosaccharides - polysaccharides
• Key enzymes of the small intestine
Small intestine: sucrase, maltase, lactase - breaks down certain sugars into simpler sugars intestinal lipase - digests fat
• Where nutrients can be stored in the body
Storing carbohydrates: - liver glycogen - muscle glycogen Storing fat: - adipose cell triglycerides
• Subcutaneous vs. Visceral fat
Subcutaneous: - accumulation of adipose cells in the tissue under the skin Visceral: - deposits of adipose tissue that are around abdominal organs and in the omentum
• Water requirements
The Adequate Intake (AI) for total water intake is approximately 11 cups (2.7 L) for young women and approximately 15.5 cups (3.7 L) for young men
• Factors influencing water balance
The body maintains the balance of compartmental fluids primarily by controlling concentrations of ions in each compartment. Ions are mineral elements or small molecules that have electrical charges, such as sodium, potassium, phosphate, and chloride ions. These ions are also called electrolytes.
• Non-exercise activity thermogenesis definition
The energy expended for everything we do other than sleeping, eating, or sports-like exercise - think fidgeting - NEAT
• Calorimetry
The precise measurement of heat flow out of the body for chemical and physical processes - direct: body's heat impact on water indirect: body's heat impact on air
• Direct vs. Indirect calorimetry
The precise measurement of heat flow out of the body for chemical and physical processes - direct: body's heat impact on water indirect: body's heat impact on air
• Small intestine - 3 parts, their sizes, and their roles
Three parts: 1. Duodenum - where most nutrients are absorbed (short) 2. Jejunum - some absorption in upper part (medium) 3. Ileum - absorbs remaining nutrients (longest) Digestions: - the major cite of chemical AND mechanical digestion through enzyme activity, peristalsis and segmentation Segmentation: the regular contractions of circular intestinal muscles followed by relaxations that mix chyme in portions of the SI - simple diffusion - high to low concentration - facilitated diffusion- transport molecule, high to low concentration - active transport - transport molecule, low to high concentration - solvent - water/osmosis - endocytosis -
• Adipose tissue, total body fat, and essential fat definitions
Total body fat: adipose tissue and essential fat Adipose tissue: fat cells Essential fat: fat that is vital for survival, found in cell membranes, certain bones, and nervous tissue
• Lipoprotein definition and structure
Very-low-density lipoproteins (VLDL) - carries triglycerides in the bloodstream Low-density lipoprotein (LDL) - carries cholesterol to tissues, HIGH LDL is linked to increased CVD High-density lipoprotein (HDL) - transports cholesterol away from tissues to the liver for elimination, LOW HDL is liked to increased CVD
• Adiponectin
a hormone produced by adipose tissue that increases muscle cells' uptake of fatty acids from the bloodstream and metabolism of the fatty acids for energy
• Oxidizing agent definition
a substance that removes electrons from atoms or molecules - an oxidation reaction can form a free radical, a substance with an unpaired electron
A
a. Retinoids (preformed vit A) vs Retinyl esters definition (storage form of vit A) vs carotenoids (yellow orange pigments in fruits and vegs) - retinol, preformed and provitamin A - fat-soluble - family of compounds commonly called vitamin A (retinol, retinal retinoic acid) - retinol: the alcohol form and most active form of vitamin A in the body - found in plants and animals Major function: normal vision, reproduction, cellular growth, immune system function sources: - preformed: liver, fortified milk, fortified cereal - provitamin: yellow-organe and dark green fruits and vegetables signs of deficiency: night blindness, xerophthalmia, poor growth, dry skin, reduced immune system function signs of toxicity: nausea, vomiting, headache, bone pain, fractures, hair loss, liver damage, interference with vitamin K absorption RDA: 700-900ug - generally met in US
• Function of lipids
absorb fat-soluble vitamins cushion body form cell membranes insulate body produce steroid hormones provide and store energy (triglycerides)
• Role of kidneys
aldosterone hormone secreted from adrenal glands in response to dehydration; stimulates kidneys to conserve sodium and water antidiuretic hormone - ADH - hormone secreted from pituitary glands in response to dehydration; stimulates kidneys to conserve water
• Obesogenic environment definition
all the factors surrounding a person that promote weight gain, such as increased food intake, especially of unhealthy choices, and decreased physical activity
• Malnutrition definition
bad-nutrition - state of health that results from improper nourishment - lack of nutrients (undernutrition) - excessive amounts of nutrients (over nutrition) - can be caused by: poor diet, disease, medication, poor sanitation, parasite, traditions, conflict/unrest, disease
• What food labels must include
country of origin - ingredients (order by weight) - amount of product - Nutritional fact panel with Daily Values (DV) -- required: total fat, cholesterol, sodium, total carbohydrate, fiber, total sugar, added sugar, protein, vitamin D, potassium, calcium, iron - serving size is set by company
• Literal meaning of term vitamin
derived from the chemical name amine and the Latin word vita, "life," because vitamins are required for life and were originally thought to be amines
• Biological activity differences
describes the vitamin's degree of potency or effect in the body - vitamin E is better in the natural form - folic acid is more active in the synthetic form
⁃ Pathogens in food
disease-causing microorganisms
⁃ Water and hydration
does not need to be digested - your body obtains water from beverages and foods, especially fruits, vegetables, and meats. The body makes some water as a result of metabolism. - body is 50-75% water - lean muscle contains more water, fat contains less - babies have more, old people less - is a major solvent for substances like glucose - Water helps transport water-soluble substances within and outside cells. The Adequate Intake (AI) for total water intake is approximately 11 cups (2.7 L) for young women and approximately 15.5 cups (3.7 L) for young men
• Color additives definition
dyes, pigments, or other substances that provide color to food
⁃ Energy balance
energy in = energy out
• Intentional additives definition
food additive assed purposefully by a food manufacturer to enhance the food
• Know the likely causes and consequences of listeriosis
food-borne illness that results from ingesting Listeria monocytogenes - often in milk or milk products that have not been pasteurized - can be passed to unborn child through placenta and result in miscarriages, premature birth - signs include fever, fatigue, aches, vomiting,
• Organic food definition and labeling rules
foods that are produced without the use of antibiotics, hormones, synthetic fertilizers and pesticides, genetic improvements, or ionizing radiation types: - 100% organic - 100% - Organic - at least 95%, 5% from allowed list - made with organic ingredients (can't use USDA seal)
• Tocopherols definition
group of four structurally similar forms of vitamin E
• Tolerable upper level intake definition and risks
highest average daily intake level of a nutrient likely to pose no risk of negative health effects - for many vitamins and minerals - usually happens through taking suppliments
⁃ Food-borne illness
infection caused by microscopic disease-causing agents in food
• Prions
infectious pathogens that are composed of misfolded proteins - mad cow disease
• Metabolism definition
involves chemical pathways that enable the human body to obtain and use energy from macronutrients and alcohol
• Cofactor definition and roles
ion or small molecule that an enzyme requires to function - magnesium and copper
⁃ Major minerals
major minerals - essential mineral elements required in amounts of 100 mg or more per day trace minerals
• Ph scale
measurement system used to indicate the concentration of hydrogen ions (H+) in solution; ranges from 0 to 14 A digestive fluid secreted by the stomach. - has a ph of 2, which is more than lemon juice
• Viruses, especially norovirus
microbe consisting of a piece of genetic material coated with protein - must have a living cell host tp produce the virus - do not secrete toxins so do not cause intoxication Norovirus: - food-borne pathogen - severe vomiting, diarrhea, cramps - most common in the US
Definition of transport
movement of nutrients to where they are needed in the body
• Genetically modified organism definition, example
new organisms created by altering the genetic material (DNA) of existing organisms; usually in an attempt to remove undesirable or create desirable characteristics in the new organism.
• Food-borne illness definition and consequences
nfection caused by microscopic disease-causing agents in food
• Role of the stomach in carbohydrate digestion
not digested in stomach
chyme
once food/the bolus enters the stomach it is called chyme
• Treating dehydration
oral rehydration therapy: specially prepared solutions of water and electrolytes used to prevent and treat dehydration
organic vs. inorganic
organic: contains carbon inorganic: does not contain carbon
• Osmosis definition
osmosis - movement of a solvent, usually water, through a selectively permeable membrane
• Retinoids definition
preformed vitamin A - family of compounds commonly called vitamin A (retinol, retinal retinoic acid)
• Pasteurization definition
process that kills the pathogens in food and beverages as well as many microbes for spoilage
• Set-point theory
scientific notion that the body's fat content and body weight is genetically predetermined
• Selectively permeable membrane definition
selectively permeable membrane - barrier that allows the passage of certain substances and prevents the movement of other substances
• Fungi
simple organisms that live on dead or decaying organic matter
• Bacteria, especially salmonella
single-cell microorganisms
• Deficiency disease definition, signs, and symptoms
state of health characterized by certain abnormal physiological changes that occur when the body lacks a nutrient
Undernutrition
state of undernutrition occurring when energy and nutrient intakes are insufficient to meet an individual's needs over an extended period of time - especially harmful during periods of rapid growth, pregnancy, infancy, childhood, elderly
• Aflatoxins
substances produced from molds that can have toxic effects when consumed
⁃ Food additives
substances that are accidentally in foods
• Pesticide definition and examples
substances used to kill or control unwanted insects, weeds, or other organisms
• When ketone bodies are formed
the by-products of the incomplete breakdown of fat
• Energy definition
the capacity to perform work - can't be created or destroyed - undergoes transformations
catabolism
the metabolic pathway that breaks down larger molecules into smaller ones - example: glycogen to glucose - result in the release of energy that is more than what is needed to create the reaction
anabolism
the metabolic pathways that build larger molecules from smaller ones - example: glucose to glycogen - they require some energy to happen - the new molecules store energy for use later
• Segmentation definition
the regular contractions of circular intestinal muscles followed by relaxations that mix chyme in portions of the SI
⁃ Water-soluble vitamins
thiamin riboflavin niacin vitamin B-6 pantothenic acid folate biotin vitamin B-12 vitamin C - dissolve in the watery components of food in the body - can leach out in water when foods are cooked/washed
• Seafood toxins
toxin that forms as a result of bacterial breakdown of fish tissue that has been improperly stored
Trace minerals
trace minerals - essential mineral elements required in amounts that are less than 100 mg per day
• Definitions of absorption
uptake and removal of nutrients from the gastrointestinal tract