Leading Causes of Death Attributed to Nutrition
Heart Disease, Cancer, Stroke
Nutrient Classification: Energy Yielding Nutrients
Carbs, Protein, Fats
Nutrient Classification: Macronutrients
Carb, Protein, Lipids, Water
Nutrient Classification: Micronutrients
B Vitamins, Vitamin C, vitamin A, Vitamin D, Vitamin E, Vitamin K, Calcium, Iron
Nutrient Classification: Inorganic
Minerals, Water
Nutrient Classification: Organic
Carbohydrates, Lipids, Protein, Vitamins
Amount of Energy Carbohydrates Provides
4 kcals
Amount of Energy Protein Provides
4 kcals
Amount of Energy Fat Provides
9 kcals
Amount of Energy Alcohol Provides
7 kcals
Nutrient Density
A measure of nutrient a food provides compared to its energy content i.e.: broccoli vs. french fries, low-fat milk vs. sweetened iced tea.
nutrient dense foods
fruit/nut trail mix, fresh fruit, baked chips, oatmeal raisin cookies
Balance Study
The type of nutrition study that focuses on the amount of nutrient consumed compared to the nutrient leaving the body
Epidemiological Study
Observing relationships between diet, health and disease patterns in different food populations
Case Control Studies
Compares individuals with a particular condition to similar individuals without the condition
Depletion-Repletion Studies
The nutrient is eliminated in the diet until deficiency symptoms appear. Then the nutrient is added back to the diet to a level which may eliminate the symptoms
A nutrition supplement or product is considered credible if...
Results were based on scientific studies that used the proper controls, adequate experimental subjects, and the data was quantifiable
Adequate Intake (AI)
Established due to insufficient scientific date to establish an EAR and calculate an RDA
Estimated Average Requirements (EARS)
Amount needed to meet 50% of people in the same gender and life-stage group
Recommended Dietary Allowances (RDA)
Intakes that meet the needs of nearly all (97-98%) of individuals in each gender and life-stage group
Tolerable Upper Intake Levels (ULs)
Maximum daily intake that is unlikely to pose a risk of adverse health effects to almost all individuals in a specific life-stage and gender group
Differences between the energy recommendations AMDR and EER
Estimated Energy Requirements (EERs): average energy intakes predicted to maintain body weight by calculating the amount of kilocalories
Acceptable Macronutrient Distribution Ranges (AMDRs): Intakes of macronutrients (carbohydrate, protein, and fat) are expressed in %. Expressed as a % of total energy intake
Dietary Guidelines
Nutrition/ lifestyle recommendations published by the U.S. Department of Health and Human Services. Only recommendation with major emphasis on FOOD SAFETY
MyPlate vs. My Pyramid Differences
Plate Shape vs. Pyramid
Protein Group vs. Meat & Beans
Section on Fats and Oils- present on the Pyramid, but not the Plate
Physical Activity Emphasis- Present on the Pyramid, but not the Plate
Exchange Lists
Based on food groups to determine overall energy and macronutrient intake
Healthy People Initiative
National health promotion and disease prevention objectives for the U.S.
Food Labels
Food and Drug Administration (FDA): regulates all foods except meat and poultry
United States Department of Agriculture (USDA): meats and poultry only
Structure/Function Label Claim
"Calcium builds strong bones"
Nutrient Content Claim
"low" "high" "free" "reduced" "lean""antioxidant"
Health Claims
Relationship between a food, food component, and a dietary supplement ingredient
Anthropometric Measurement
Weight, height, or skin fold evaluation
Organization of Life
Atoms, Molecule, Cells, Tissues, Organ, Organ System
Organs of the Digestive System: Mouth
Chews food and mixes it with saliva
Organs of the Digestive System: Salivary Glands
Produce saliva, which contains starch-digesting enzyme
Organs of the Digestive System: Pharynx
Swallows chewed food mixed with saliva
Organs of the Digestive System: Esophagus
Moves food to the stomach
Organs of the Digestive System: Stomach
Churns and mixes food; secretes acid and a protein-digesting enzyme
Organs of the Digestive System: Liver
Makes bile, which aids in digestion and absorption of fat
Organs of the Digestive System: Pancreas
Releases bicarbonate to neutralize intestinal contents; produces enzymes that digest carbohydrate, protein, and fat
Organs of the Digestive System: Gallbladder
Stores bile and releases it into the small intestine when needed
Organs of the Digestive System: Small Intestine
Completes digestion; absorbs nutrients into blood or lymph
Main site of digestion and absorption in the body
Organs of the Digestive System: Large Intestine
Absorbs water and some vitamins and minerals; home to intestinal bacteria; passes waste material
Organs of the Digestive System: Anus
Opens to allow waste to leave the body
Accessory Organs of the Digestive System
Pancreas, Liver, Gallbladder
Digestive Enzymes
Protein molecules that speed up the rate of chemical reactions without undergoing any changes. Accelerate the nutrient breakdown during digestion. Specific enzymes that break down different nutrients
Digestive Enzymes: Amylase
Location: Mouth
Breaks starch into shorter chains of glucose
Digestive Enzymes: Lactase
Breaks lactose into glucose and galactose
Digestive Enzymes: Maltase
Breaks maltose into glucose
Digestive Enzymes: Sucrase
Breaks sucrose into glucose and fructose
Digestive Enzymes: Lipase
Breaks triglycerides into monoglycerides, fatty acids, and glycerol
Digestive Enzymes: Pepsin
Breaks proteins into polypeptides and amino acids
Heartburn
Stomach acids leaking into the esophagus
Peptic Ulcers
erosion on stomach or esophageal wall due to H. pylori exposure, or use of aspirin or ibuprofen
Cardiovascular System
Transports carbohydrates and proteins
Collects nutrient-rich blood form the digestive organs and delivers them to the liver
Lymphatic System
Transport lipids (via lacteals)
Drains excess fluid from the spaces between cells, transports fat-soluble substance from the digestive tract, contributor to immune function.
Lacteals transport fat digestion products
Catabolism
Breaking down substances for energy where nutrients are used as fuel
Anabolism
Smaller molecules combine to form complex substances where nutrients are used as raw materials
Metabolic Wastes from the Lungs and Skin
Water, minerals, and carbon dioxide
Metabolic Wastes from the Urinary System
Water, minerals, metabolic waste products
Refined Carbohydrates
Refers to foods that have undergone processing that changes or removes various components of the original food
Unrefined Carbohydrates
Natural sources of food i.e.: oatmeal, whole-wheat bread, whole-wheat pasta, raspberries, baked potato
Structure of a Grain
Endosperm: starch & protein
Bran: fiber & vitamins
Germ: vegetable oils & vitamin E
Carb Classification: Monosaccharides
Glucose, galactose, and fructose
Carb Classification: Disaccharides
Maltose, sucrose, and lactose
Carb Classification: Polysaccharides
Glycogen (humans and animals), starch (plants), and fiber
Role of Fiber in Digestion
Slows nutrient absorption (followed by gradual rise of glucose in the blood)
Metabolic Reactions: Breakdown of Carbs Glycolysis
Takes place in the Cytoplasm of the cell. Anaerobic Reaction
Glucose is broken down to form ATP electrons and two Pyruvate.
Metabolic Reactions: Breakdown of Carbs Acetyl CoA Formation
Takes place in the Mitochondria and is An Aerobic reaction.
Pyruvate is broken down to form three products are formed from this reaction, Carbon Dioxide, Electrons, and Acetyl CoA
Metabolic Reactions: Breakdown of Carbs Citric Acid Cycle
Takes place in the Mitochondria and is an Aerobic reaction.
Acetyl CoA and Oxaloacetate trigger this reaction and in turn form three products, carbon dioxide, electrons and ATP
Metabolic Reactions: Breakdown of Carbs Electron Transport Chain
Takes place in the Mitochondria and is an aerobic reaction.
Glucose Regulation: Role of Insulin
Released so that glucose can be taken into cells to lower glucose concentrations back to fasting levels
Glucose Regulation: Role of Glucagon Hormones
Released so that glycogen can be broken down and glucose can be synthesized in response to low blood sugar
Type 1 Diabetes
Autoimmune disease. Immune system destroys the cells that make insulin. Typically diagnosed before age 30, 5-10% of diagnosed cases of diabetes. Genetics, viral infections, toxin exposure, abnormalities in immune system
Type 2 Diabetes
Accounts for 95% of diagnosed cases of diabetes. Insulin resistance (cells do not respond to insulin) therefore limited glucose enters cells. Family history, overweight sedentary lifestyle. Present in native americans, alaskan, african american and hispanic minority groups
Gestational Diabetes
Pregnancy, possible causes lay within hormonal changes. High levels of glucose in the mother's blood can increase risk of complications for the unborn child. Disappears after birth, but may have increased risk for developing type 2 diabetes
Fiber- Role in Protecting Against Heart Disease
Diets high in sugar may raise blood lipid levels and increase hearth disease risk. Diets high in whole grains have been found to reduce risk of heart disease.
W/o Soluble Fiber: Bile and dietary cholesterol are absorbed into the blood stream
With Soluble Fiber: Bile and dietary cholesterol are excreted in the feces
Carbohydrate Recommendations RDA & Fiber
RDA: 130 g/day (adults and children)
Fiber: 25 g for female; 38 g for males
Calculating Percent Energy from Carbohydrate
Energy from carbs = g carbohydrate x 4 kcal/g
% Energy = kcal carbs/total carbs x 100
Lipids
Organic molecules that are not soluble in water (soluble in fat only)
Types of Lipids: Triglycerides
Comprised of glycerol backbone attached to 3 fatty acids and glycerol molecule
Types of Lipids: Phospholipids
Phosphorus chemical group attached to lipids. Glycerol molecule, two fatty acids, and a phosphate group
Types of Lipids: Cholesterol
Cholesterol is a type of sterol found only in animals. 90% of cholesterol in the body is found in cell membranes. Diets high in cholesterol (from animals) can increase the risk of heart disease. Plant sterols can help reduce cholesterol in the body
Saturated Fat
Carbon and hydrogen atoms- single bonds in between carbon atoms
Unsaturated Fat
Contains some carbons that are not saturated with hydrogens (C=C bonding)
Monounsaturated Fatty Acids: unsaturated fatty acid with one carbon-carbon double bond
Polyunsaturated Fatty Acid: unsaturated fatty acid with two or more carbon-carbon double bonds
Cis Fatty Acids
Hydrogens are on the same side of the double bond and cause a bend in the carbon chain
Trans Fatty Acid
An unsaturated fatty acid in which the hydrogen atoms are on opposite sides of the double bond
Hydrogenation
The process that forms trans fats
Beta-Oxidation
Breaks down fatty acid into acetyl CoA
Deamination
Removal of Nitrogen Group; amino acid into acetyl CoA
Glycolysis
Breakdown of carbs into pyruvate
Lipid Digestion Process: Step 1
A small amount of digestion occurs in the stomach due to the action of gastric lipase produced in the stomach
Lipid Digestion Process: Step 2
The liver produces bile, which is stored in the gallbladder and released into the small intestine to aid in the digestion and absorption of fat
Lipid Digestion Process: Step 3
The pancreas produces the enzyme pancreatic lipase, which is released into the small intestine to break down triglycerides into monoglycerides, fatty acids, and glycerol
Lipid Digestion Process: Step 4
In the small intestine, the products of fat digestion and bile acids form micelles, which move close enough to the microvilli to allow lipids to diffuse into the mucosal cells
Lipid Digestion Process: Step 5
Inside the mucosal cells, fatty acids and monoglycerides are reassembled into triglycerides and incorporated into lipid transport particles, which enter the lymph
Lipid Digestion Process: Step 6
Since fat absorption in the small intestine is efficient, very little fat is normal lost in the feces
Role of Lipoproteins: Chylomicrons
Transport lipids from the mucosal cells of the small intestine via the lacteals
Role of Lipoproteins: VLDL (Very-low-density lipoproteins)
Packages cholesterol and triglycerides in the liver. Transport protein that delivers lipids to the body cells. Becomes smaller in size when triglycerides are removed
Role of Lipoproteins: HDL (High-density lipoprotein)
Picks up cholesterol from cells and transports it to the liver so that the cholesterol can be eliminated from the body.
High levels decrease cardiovascular disease risk
Role of Lipoproteins: LDL (Low-density lipoproteins)
Binds to the LDL Receptor on the cell membrane. LDL is internalized into the cell. Few LDL receptors result in high blood cholesterol with an increased risk for heart disease