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The proteasome : system that degrades proteins within cells discovered in 1990s DRI : developed during WW EAR : good estimate done due to studies RDA : strongest DRI because many balance studies done, scientist agreed with final value Upper limit DRI of a nutrient: highest amount able to consume without toxicity Joseph Goldberger : scientist in charge of investigating outbreak of pellegra Fire and metabolism : both need oxygen, provide fuel, create C Fire works : binds between atoms in fuel are split and oxygen carries away the electrons and the carbon atoms of fuel Fat: 9kcal/gram Gas: 11kcal/gram Alc: 7kcal/gram Eric Heiden : highest VO2 max ATP (adenosine triphosphate): molecule formed from energy in the body that allows movement Starch : long chains of glucose (glucose is made by plants) stored in endosperm of plants (seeds and kernels), similar to glycogen Thortons rule: energy used/release is related to oxygen consumed: we use for sleep, biking, bowling, running Disaccharide : 2 glucoses linked together. A glucose and a… Glycogen found in humans is: very small- just enough for about a day or two Starch can be used to make high fructose corn syrup Glucose is co-transported with sodium into enterocyte cell The discovery in 1960 of the biochemical mechanism of glucose transport into the enterocyte cell led to: hydration therapy for infants and cholera victims Newly absorbed amino acids travel first in the blood past the pancreas and then to the liver The high efficiency in which amino acids from newly degraded cellular protein proteins are reused within cells for new protein synthesis explains why the protein requirement for adults is fairly low In vitro : invoking use of cells not part of living organisms “in glass/outside” In vivo : involving study or natural phenomena in living organism RCT : randomized, double-blind, placebo controlled ( find strongest method for testing treatment intervention) Nutrition is updated every 5 years Atwater number are accurate Cooking starches and meats are absorbed getting cause heat begins breaking down molecule and extract energy and nutrients 1900 cause of death: infectious diseases, diarrhea, pneumonia, strokes 1950 : chronic diseases, heart disease, cancer, infectious, antibiotics helped reduced infectious diseases Today : chronic, heart, cancer, stroke, lower respiratory diseases Macronutrients : carbs, proteins, fats (are energy yielding) Micronutrients : vitamins, minerals, water Organic contains carbon, inorganic doesn’t Zoonutrients: compounds in animal-based foods giving nutrients and energy ATP : bodies molecular battery, is the reason we can move Gobekli Tepe : older temple
- people are better nutrient flour
Pellegra : niacin deficiency common after roller milling (white flour) bran and germ removed (nutrient). Came from untreated corn- cornbread, grits, maize based meals lacking niacin and tryptophan. People though it was insect born fleas) Milling : decreases nutrient Brand : fibers Germ : vitamins Pellegra appeared in US because: many people ate corn, lacks niacin (Vitamin b3), poverty and poor 3M diet: meat, molasses , maize (corn) 1st report of pellegra: Georgia 1902 Dr. Joseph Goldberger : discovered pellagra wasn’t contagious, it was from poor nutrient Nicotinic acid : type of vitamin B3 helps body turn food into energy and keep skin nerves and digestion healthy 1941 : flour was ordered to be enriches with all nutrients (corn needed soaking in limewater for absorption) Brewers yeast : found by Goldberger, rich in niacin, cured black tongue in dogs Conrad Elvehjem : biochemist who identified niacin was the vitamin deficient in pellagra Discovery of essential nutrients (vitamins) and nutrient balance studies: 1st Foundation of nutrition 1990s-1950s Atwater numbers : measure energy in food Nutrition balance studies: performed in humans and health learn about the nutrient (vitamin) and how much is needed daily Scurvy : lack of vitamin C, sailors given citrus in Cape of Good Hope EAR (estimated average requirement): intake to meet mean requirement of healthy individuals in particular life stage RDA (recommended dietary allowance): better, more data, average daily amount of a nutrient considered adequate to meet the know nutrient needs of practically all healthy people
DV (daily value) amount of nutrient recommended to be consumed to maintain good health, based on 2,000 or 2,500 calorie
diet, ages 4 and older use AI, EAR, RDA Taking less vitamins is: better DSHEA : Dietary supplement health and education act in 1994, FDA lost against them, 50$ billion in sales, playbook was formatted by tobacco industry to neutralize criticism and undercut calls for regulation, used in pharmaceutical co., food co., food supplement co, politics, antivax Big food companies: owned by historically known tobacco companies Olestra : fat substitute failed because too much causes diarrhea Sugar sweetened beverages (SSB ): one of largest source of added sugar in diet Marion Nestle : provided insights on how industries support scientist in different field of nutritional research, probably most studied with industry funding are tainted are reasonable We are the food industry’s: Guinea pigs, they won, we behold them Synaptic pruning : process where the synaptic connections in the brain that are used are preserved, and that’s aren’t are lost- happens with maturity Energy comes from photosynthesis : plants make glucose and which that starch (stored energy) or cellulose (used by every plant cell for structure) Starch : long chains of glucose linked by alpha bonds (stored) Cellulose : long chains of glucose linked by beta bonds (structure) Chemical bonds : attractive forces that hold atoms together, lets them form different molecules Valence shell electrons : outermost shell “glue’ that holds atoms together in a molecule by forming chemical bonds Methane (CH4 ); simplest carbon, organic, burn things Hydrogen : 1 proton, 1 electron Molecular energy : amount of energy found in a molecule and is determined by the shape of the molecule
Endosperm : starches and proteins macronutrient Bran : fiber, protects grain Amylose : simplest starch, straight chained Amylopectin : branched, holds water Lipid transport protein : protein molecule that moves lipids between cellular membranes by binding them in a hydrophobic pocket and transferring them through aqueous cytoplasm Potato’s have: amylose and amylopectin Fructose : naturally occurring monosaccharides: honey, fruit, veg, sweetest monosaccharide (corn syrup) Galactose : few foods contain it, easily converted to glucose, used for energy Disaccharide : double sugar, 2 monosaccharide, glucose +… Poly : carbs made of more than two monosaccharides Glycogen : in humans and aminals, many branch points allowing for rapid break down for glucose to be release A lot of carbs stored in body? No very little, plants store more than us. 2600 kcal carb in body Triglycerides (fats storage); 95,600 kcal Protein storage : 24,000 kcal Muscle glycogen : 2,000 kcal Liver glycogen ; 570 kcal Foods that contain mostly starches are called: principle starches about 74% starch and 11% fiber Starch can’t have a lot of protein Paleo diet : myths, people were hunters and gathers but mostly gatherers-women supplied most calories Corn : largest crop in US 110,000 million pounds Most consumed veg: potatoes and tomatoes Sugar : disaccharide, entered English diet around 1650 as sucrose Monosaccharides : glucose, fructose, galactose (one sugar) Sweeteners haven’t gown up in past 40 years Dietary fiber : plant polysaccharides that humans can’t digest in in SI Humans can break alpha bonds in carbs like starch but Only bacteria can break beta bonds in cellulose- why humans can’t digest starch but not fiber Pectin : glue, one of soluble fibers Cellulose : largest soluble fiber Galactose : milk sugar Fruits have: soluble fiber Grains have: insoluble fiber (not dissolve in water) Barley malted starch : able to make beer discovered with bread left out Look for 100% whole grain Men/women fiber intake: 38g/25g (avg. us intake is 13-17g) Glucose goes to liver , muscle , and fat Pancreas : produces insulin and glucagon B cells : increase blood glucose A cells : decrease blood glucose Insulin : lowers blood glucose, small peptide protein hormone, tranced to blood signal tissues to respond to glucose, binds to insulins, in liver speeds up metabolism, moderately stimulates protein synthesis Glucagon : raises blood glucose Type 1 diabetes: childhood, low insulin, need insulin injection, lack of insulin secretion
Type 2 diabetes: body is resistant to insulin, due to obesity, transport of glucose to muscle is slowed, adult onset, lack of insulin response, loosing weight can reverse this PVD: legs feet arms don’t have enough blood circulation Diabetes : body isnt able to effectively produce or use insulin, blood glucose increases- hyperglycemia, fatty liver can be reversed Amino acid : building block protein, body uses 20 to make proteins, contain nitrogen 9 -essential 11 -nonessential Nitrogen : secreted in urine as urea Oxygen is secreted as water or part of C Aminos acids can link together and form peptide bind and proteins Proteins are long chains of amino acids that perform almost every function imaginable in cells in our body (support, catalyst, transport, defense, movement, regulation, stay in cells) SOLUBLE Peptide bond : bonds that connect amino acids (2+) Protein synthesis : formation of proteins by using information contained in DNA and carried by mRNA Requirement for protein is really a requirement for amino acids, can feed no protein but all essential aminos acids and nutrients and be fine Proteins are secreted from cells by digestive enzymes, blood proteins, clotting proteins, apoliproteins, and enterocytes Proteins come in different shapes and sizes and are highly digestible High quality protein : contain adequate amounts of all essential amino acids, important for infants Low quality protein : incomplete, low amounts of 1 essential or more amino acids (corn, gelatin) Intake of protein and zinc correlate with good growth in humans Growth spurt : in stairs, not enough then growing stops and stops too many times = stunted, can resume after getting complete protein Infections : leading chase of stunting Egg protein : highest quality protein Chemical score of protein : taking lowest essential aminos acids in a grain of protein in food and basing it on egg. Based on amino acid patterns and estimates of digest ability Pea protein : low in methionine and cysteine, good vegetable protein, Plants and aminals all have: carbs, proteins, and fat Every plant cell needs to have: protein in it Proteins digested: gastrin , HCl acid, Secretin : food enters SI and this is secreted by cells of upper intestine which causes the release of enzymes from pancreas Leucine : causes insulin secretion Amino acids to to all cells and tissues: liver , muscle , fat Protein synthesis / degradation : controlled by muscle, a lot of amino acids increases synthesis and drastically decrease degradation. Synthesis is consistent except after a meal and exercise (tortoise) speed up and jump (hair). Synthesis requires all essential amino acids (10) and if you miss one synthesis will stop. Synthesis increases after meal. Degradation increases during injury, stress, cancer, older people. Synthesis varies during day breakfast is better Body normal recycles 90-95% amino acids in body How much protein is in a tissue like muscle depends on the relative rates of protein synthesis and protein degradation in the cells of that tissue 2 ways to stimulate protein synthesis: 1. Amino acid availability (leucine) activating mTORC1, 2. Insulin and Glucose uptake
