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Life Sciences
Danny M.Pincivero

Introduction to Nutrition: What is nutrition?  All processes involved in the talking in and utilization of food substances; by which growth, repair, and maintenance of activities in the body o Includes ingestion, digestion, absorption and metabolism What is food?  Any material that provides the nutritive requirements of an organism to maintain growth and physical well being What role does food play in the world?  Social welfare  Geopolitics  Nutrition and health  Armed conflict  Economic prosperity Food, science and world peace?  Norman Borlaug won Nobel Peace Prize; invented strain of wheat which was disease resistant and generated high yields to combat world hunger before getting it copyrighted/patented Why is nutrition important?  Can prevent disease o Diseases caused by nutrient deficiency:  Scurvy  Goiter  Rickets o Diseases influenced by nutrition:  Chronic diseases (i.e. heart disease) o Disease in which nutrition plays a role:  Osteoarthritis  Osteoporosis o Occupational health: meaningful work or vocation o Physical health: includes nutrition and physical activity o Spiritual health: spiritual values and beliefs o Emotional health: includes positive feelings about oneself and life o Social health: includes family, community, and social environment Why we eat the way we do? 1. Physiological hunger; regulated by insulin and leptin 2. Sensory stimulation; food flavor and texture 3. Personal preferences 4. Habits: 3 meals/day 5. Ethnic heritage or tradition; cultural beliefs and traditions, religion 6. Social interactions 7. Availability, convenience, and economy 8. Positive and negative association: commercial advertising 9. Emotions: comfort; instinctive for newborns, cravings, pica 10. Values 11. Body weight and image 12. Nutrition and health benefits Sports supplements; mostly not worth it unless intensely training 1. Sports drinks o Provide CHOs and fluid, enhance exercise performance and recovery 2. Sports food o Found in bar format o Nutrient dense; provides health benefits beyond their nutritional value o Whey and soy 3. Sports supplements o Build muscle tissue, increase energy stores, decrease body fat o Tablets, powders, ready to drink o Whey, soy, creatine, L-canitine and amino acids Nutrient: any substance in food that the body can use to obtain energy, synthesize tissues, or regulate physiological/physical functions Essential nutrient: a substance that must be ingested because the body cannot make it or adequate amounts of it Macronutrient: a nutrient that is needed in relatively large amounts in the diet  Carbohydrates o Purpose; supply energy to cell o Storage; liver and skeletal muscles o Example food sources; simple or complex CHOs o Problems/diseases specific to CHO; diabetes mellitus  Lipids: fats, oils, cholesterol, phospholipids o Purpose;  building block of phospholipids and glycolipids,  protein modification by attaching to fatty acids,  fuel,  derivatives serve as hormones and intracellular messengers o Storage; white and brown adipose tissues (WAT & BAT) o Example food sources; meat, dairy, coconut, olives, avocado o Problems/diseases specific to lipids; obesity, coronary heart disease, coronary artery disease  Proteins o Purpose; structure and energy o Storage; all tissue o Example food sources; meat fish, dairy, grain, legumes, veggies o Problems/diseases specific to protein; kwashiortor (lack of protein, fat deposits on liver, swelling), excess protein linked to heart disease, increased fat, cancer and osteoporosis  Non-protein nitrogenous compounds o Composed of amino acids, but not considered to be proteins  Glutathione  Carnitine  Carnosine  Creatine  Choline Micronutrients: a nutrient that is needed in relatively small amounts in the diet  Vitamins: organic compounds containing C and H (and N, O, P) o Function;  Energy extraction from macronutrients  Calcium balance  Blood clotting o 2 groups: 1. Water soluble: B viatmins (8) and vitamin C 2. Fat soluble: vitamin A, D, E, K  Minerals: inorganic nutrient needed for growth/regulation of normal physiology (16 minerals) o Macrominerals: major minerals required in the diet in larger amounts than the trace minerals  Na, K, Cl, Ca, P, Mg, S o Trace minerals: required in small amounts in the diet  Fe, Zn, Cu, Mo, Mn, Se, I, Fl  Water; considered a nutrient Organic food: food growth without use of fertilizer, hormones, antibiotics, etc  Must meet standards of Canadian Organic Products Regulations  Crop production  Livestock production  Processing  Cleaners, disinfectants, sanitizers  Health care products Antioxidant: a nutrient that combines with or neutralizes free radicals, preventing oxidative damage to the cell  Exercise increases free radical production Phytochemicals:  Plant chemical  Complex chemicals that vary from plant to plant  Function: fight bacteria and viruses, UV lights, free radicals  Health benefits: cancer prevention (free radical and hormone neutralizing), lowers cholesterol What is energy?  An ability to cause changes in, or perform, work, heat and/or mass o calorie : the amount of energy needed to raise the temperature of 1 gram of water by 1 degree o 1, 000 calories = 1 kcalorie = 1 Calorie  Energy density: amount of energy in a food source relative to its’ mass; less energy dense foods are usually healthier  Nutrient density: amount of nutrients in a food source relative to its’ energy content; more nutrient dense foods are usually healthier  Food energy is in the chemical bonds  Nutrients provide energy via macronutrients  Food energy is used for metabolism to support life Energy Balance Equation: EIN E OUT+ E STORED How much energy macronutrients provide;  Carbohydrates = 4 kcal/gram  Proteins = 4 kcal/gram  Lipids (fats) = 9 kcal/gram Ex/ half an avocado; 101 g, 2 g of protein, 9 g of CHOs, 15 g of fat = 161 kcalories (2 x 4) + (9 x 4) + (15 x 9) = 179 kcalories Why do they not add up?  When you take a look at individual macronutrients; not all carbs are exactly the same: o Starch (complex carbs; storage form of carbs in fruits and vegetables) o Fibre (complex carbs; monosaccharides connected chemically in way that digestive system cannot break apart, for absorption; enzymes are required) o Sugar (simple carbs) Dietary Reference Intakes:  Standards defined for energy nutrients, other dietary components, physical activity  Recommendations apply to healthy people; may be different for specific groups Estimated Average Requirement (EAR):  average daily intake level of a nutrient that will meet the needs of half of the people in a particular category  used to establish the RDA Recommended Dietary Allowances (RDA):  the average daily intake level required to meet the needs of 97-98% of people in a particular category o example; protein intake for a 19 year old woman ~ 46 g/day (10-35% should be protein)  dependent on exercise level, mass etc. Adequate Intake (AI):  recommended average daily intake level for a nutrient  based on observations and estimates from experiments  used when the RDA is not yet established eg. calcium, vitamin D, fluoride o example: vitamin K for 15 year old male = 75 ug/day o blood clotting factor synthesis, bone protein formation o sources: liver, green leafy vegetables, cabbage family Tolerable Upper Intake Level (UL):  highest average daily intake level that is not likely to have adverse effects on the health of most people  consumption of a nutrient at levels above the UL is not considered safe  protects against over-consumption o example: vitamin C; antioxidant, promotes iron absorption, amino acid metabolism o toxicity: nausea, abdominal cramps, diarrhea, hemolytic anemia Estimated Energy Requirement (EER):  average dietary energy intake (kcal) to maintain energy balance  based on age, gender, weight, height, level of physical activity Acceptable Macronutrient Distribution Ranges (AMDR)  describes the portion of the energy intake that should come from each macronutrient  expressed as ranges (percentage of total energy) with upper and lower boundary o CHOs – 45-65% o Fats – 20-30% o Proteins – 10-35% Nutrition Assessment: Individual Level:  Deficiency of excess over time leads to malnutrition  Symptoms of malnutrition o Diarrhea o Skin rashes o Fatigue o Others  Total picture of an individual; o Historical information; health status, diet history o Anthropometric measurements; height and weight o Physical examinations o Laboratory tests Basics of a Healthy Diet: Adequate Diet: a diet that provides enough of the energy, nutrients, and fibre to maintain a person’s health Moderation: refers to eating the “right” amounts of foods to maintain a healthy wright and optimize the body’s metabolic processes Goal: gauge energy intake with energy expenditure on a daily basis Balanced Diet: a diet that contains the combinations of foods that provide the proper balance of nutrients Variety: refers to eating many different foods each day Energy density: amount of energy in a food source relative to its’ mass Nutrient density: amount of nutrients in a food source relative to its’ energy content Canada’s Food Guide:  Designed to reduce the risk of chronic disease and obesity through healthy eating  Food groups; vegetable and fruit, grain products, milk and alternatives, meat and alternatives Daily Values:  Amount of nutrients provided in a serving of food  Uses 2 reference points; 1. Recommended Daily Intakes: most vitamins and minerals 2. Reference Standards Food Groups: 1. Breads and cereals (wheat, rice, maize, oats, barley, rye)  Provides starch and dietary fibre (70-77% of the grain)  Protein (6-15% of the grain) o Gluten – major protein in wheat and rye o Oryzenin – major protein in rice  Whole grains (whole rather than refined) – higher thiamin, vit. E and fibre  Grains: o Provides CHO, fibre, B-vitamins o Wheat plant: endosperm, germ, bran, husk o Refined: finely ground endosperm, low in nutrients (all that is left is starch component) o Enriched: nutrients added back in after processing o Whole grain: food made from the entire grain  Wheats: o Covers more the earth’s surface than any other crop o Requires milling and sifting; produces flour, bran, germ, semolina (pasta)  White flour: o Outer portion of kernel is removed; decreased nutrient content (unless enriched)  Rice: o Feeds over half the worlds population o Brown rice – bran layer is retained (healthier) o White rice – brown rice is milled and polished (virtually no thiamin)  Maize (American corn): o Dry milled (protein and starch not separated); corn meal, grits, flour o Wet milled (protein and starch separated); starch, dextrose, corn syrup solids, glucose  Oats: o Steamed or kiln-dried, then dehulled o Rolled (to make oat flakes) o Granulated (fine oatmeal) o Advertised to have a cholesterol lowering effect (significant amount of dietary fibre inhibits absorption of dietary cholesterol)  Barley: o Milled (same processing as wheat) o Used for baking, brewing, vinegar, soups, flour for flatbread  Rye: o Milled and baked into bread and breakfast cereals 2. Legumes:  Edible seeds from the Leguminosae family  Dried peas, beans, soya beans, lentils, peanuts  Most adequately meets RDA standards  High in CHO and fibre  Adequate level of protein (soya beans, lentils, provide complete PRO)  Vitamins/minerals (thiamin, niacin, zinc, calcium, magnesium)  Low in fat (except soya beans and peanuts) mostly monounsaturated and polyunsaturated (healthier fat) 3. Nuts and Seeds:  Eaten raw or roasted, processed for oil  Nuts; almonds, walnuts, pecans, cashews  Seeds; sunflower, sesame, pumpkin  Regular consumption decreases risk for coronary artery disease (action of the vit E and unsat. fat) 4. Fruit  Fleshy or dry ripened ovary of a plant enclosing the seeds  Inadequate in protein, sodium, calcium, iron, zinc  Low in energy (fat); nutrient dense  Higher intake related to decreased risk of heart disease, stroke, cancer o Mainly because of fibre content and low saturated fats 5. Vegetables  Refers to any plant part, except for seeds and fruit 6. Milk and milk products o Delivers water, high quality protein o Carbohydrate: lactose digested by lactase o Fat: 25% monounsaturated, 66% saturated o Vitamins/minerals: calcium, vitamin D (fortified), vitamin A  Pasteurization: o Destroys disease causing bacteria o Heated to 72 deg C for 15 seconds, then immediately cooled  Yogurt: o Contains less lactose than milk, but more sugar (if sweetened) o Probiotics: live bacterial cultures to aid GI health  Cheese: o Concentrated source of many milk nutrients, more fat and sodium o Less protein because whey is filtered out 7. Meat and poultry o Encompasses muscle tissue and organs (liver, kidneys, stomach) o High source of protein and minerals (Fe, Zn, K) and fat o Iron more bioavailable than plant iron  Meat products: o Curing (ham and bacon); nitrates and nitrites added as a preservative  Related to cancer due to preservatives o Short shelf life; stored at low temperatures to prevent microbial growth 8. Fish and seafood o High quality protein o Fat content: 0.5% to 15% o Fish oils: long chain omega-3 fatty acids (EPA and DHA) o B-vitamins, vitamin D, vitamin E o Fatty fish (salmon); grilled or baked o Lean fish (cod); fried  Dangers: o Undercooked fish; tapeworms active (destroys B-vitamins) o Tetradoxin poisoning (puffer fish) o Bacterial spoilage o Metal (mercury) contamination (tuna)  Health benefits: o Cardioprotective (due to omega-3 fatty acids) o Try to minimize addition of saturated fats (frying) and salt 9. Eggs  High quality protein, high bioavailability  Yolk contains high cholesterol  Whites contain “good stuff” (protein, vitamins, water) 10. Fats and oils o If solid at room temperature = fat, if liquid = oil o Over consumption is health concern o Main source: dairy products, vegetable oils/spreads, baked goods o Saturated and trans-type fatty acids linked to cardiovascular disease  Unsaturated oils: o Prone to oxidation and light damage (store in dark, sealed container) o Polyunsaturated decomposes at high temperatures  Plant sterols: o Plant counterpart to animal-based cholesterol o Inhibits the absorption of cholesterol in GI system o >1.5 g plant sterols will reduce blood cholesterol by 10-15%  Animal fat: o High in saturated fat and cholesterol  Vegetable fat: o Seed: canola, sunflower, safflower o Legumes: soybean, peanut o Fruits: olive  Extra virgin olive oil: o Made by cold-pressing (temperature controlled crushing of olives) o Vitamin E and anti-oxidant loss is minimized (costs money) 11. Herbs and spices o Spices: parts of dried seeds, bark or root o Herbs: fresh or dried leaves of plants, used as ingredients for medicine  Presents a very concentrated form of plant chemicals, not usually nutrients  Used to add distinctive flavor to food  Parsley: calcium and iron  Fresh herbs: source of beta-carotene and vitamin C (removed by drying and grinding)  High anti-oxidant activity: oregano, sage, peppermint, thyme, bay leaf, dill, rosemary  Anti-carcinogenic properties: basil, mint, oregano, rosemary, ginger (anti-emetic), parsley Anatomy and Physiology of Digestion: Digestive System: 2 main groups; 1. Alimentary canal  Gastrointestinal tract  Continuous digestive tube through whole body  Function: o Digestion;  Breaks food into smaller fragments  CHOS – must be broken down into smaller fragments  monosaccharides  Fats/lipids – must be broken down into smaller fragments  fatty acids  Proteins – must be broken down into smaller fragments  amino acids (building blocks for life)  Monosaccharides, fatty acids, and amino acids are the smallest “usable” fragments o Absorption;  Moves the digested fragments from the alimentary canal into the blood, food not absorbed will continue along the canal and be excreted  Anatomical structures; o Mouth (lips, cheeks, palate, tongue, teeth, salivary glands) o Pharynx o Esophagus o Stomach (cardiac orifice, fundus, body, pyloric canal, pylorus, pyloric sphincter, omentum) o Small intestine (duodenum, jejunum, ilieum)** o Large intestine (cecum, ascending colon, transverse colon, descending colon, sigmoid colon, rectum, anal canal) ** major absorptive organ 2. Accessory digestive organs  Refers to the breaking down of food into manageable molecules  Teeth, tongue, gallbladder, liver, pancreas Digestive System Activities: 6 essential activities; 1. Ingestion  physically taking food into the digestive system o the act of eating 2. Propulsion  moving food through the alimentary canal; muscles in and around the mouth a. Swallowing  Voluntary
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