Nutrition Essentials and Dietary Guidelines

8 Essential Amino Acids

• Threonine, valine, tryptophan, isoleucine, leucine, lysine, phenylalanine, methionine

2 Essential Fatty Acids

• Linoleic acid and linolenic acid

Essential Vitamins

• Fat-soluble (A, D, E, K) and water-soluble

Epidemiological Studies

• Large-scale comparisons between populations

Intervention Studies

• Manipulating populations

Longitudinal Studies

• Research that follows and retests the same people over time

Registered Dietitian Requirements

• Term regulated by law
• Member of provincial regulatory board
• Optional: Membership with Dieticians of Canada
• Undergraduate degree + internship

Diet Recall vs Record

• 24 hours, client may lie
• 3-5 days, recording may change eating habits

AMDR

• Acceptable Macronutrient Distribution Range
• CHO: 45-65%
• Fat: 20-35%
• Protein: 10-35%

RDA

• Recommended Dietary Allowance: intake goals

EAR

• Estimated Average Requirement: average intake based on life stages

AI

• Adequate Intake

UL

• Tolerable Upper Intake Level

Factors Not Considered in DRI

• Activity level
• Diet type
• Geography/socioeconomic/cultural
• Illness/disease states

Factors Considered in DRI

• BMI
• Age

Nutritional Labelling Micronutrient Requirements

• Sodium, calcium, iron, potassium

Benefit of a Diet Low in Sodium and High in Potassium

• Less hypertension

Benefit of Calcium and Vitamin D in the Diet

• Less osteoporosis

Benefit of a Diet Low in Saturated and Trans Fats

• Less heart disease

Benefit of a Diet High in Fruits and Vegetables

• Less cancer

Benefit of a Diet Low in Fermentable Carbohydrates

• Less dental caries

Phytochemicals

• Natural plant compounds with potential health benefits

Phytochemical Found in Tomatoes

• Lycopene

Phytochemical Found in Garlic

• Organosulfur

Phytochemical Found in Flaxseeds

• Lignans

Role of Flavonoids in Health

• Antioxidants

Foods Rich in Flavonoids

• Soy, wine, tea, chocolate

Health Benefit of Phytoestrogens

• Osteoporosis prevention

Functional Foods

• Contain biologically active compounds
• Benefits beyond basic nutrition

Parasympathetic Nervous System (Digestion)

• Regulates digestion via gastric juices

Sympathetic Nervous System

• Stress, "fight or flight"

Bile

• Cholesterol-containing digestive fluid that emulsifies fat
• Made by the liver, stored in the gallbladder, released in the small intestine

Nutrient Absorption

• Movement of nutrients from the small intestine into the blood or lymph via villi and microvilli

Nutrient Transport for Water-Soluble Nutrients

• Via blood; small intestine -> processed in liver -> liver distributes to the rest of the body

Nutrient Transport for Fat-Soluble Nutrients

• Via lymphatic system; small intestine -> lymph system

Stomach Chemical Digestion

• Gastric juices (hydrochloric acid (HCl) and pepsin, etc.)
• Hydrochloric acid: strong acid/low pH
• Pepsin: enzyme to break down protein

Small Intestine in Digestion

• Pancreas (Bicarbonate neutralizes acid. Enzymes to break down CHO, protein, and fat)
• Liver and gallbladder (bile emulsifies fat)

Enzyme for Carbohydrate Digestion (Pancreas)

• Pancreatic amylase

Enzyme for Fat Digestion (Pancreas)

• Pancreatic lipase

Enzyme for Protein Digestion (Pancreas)

• Trypsin and chymotrypsin

Liver and Gallbladder Function

• Creation and storage of bile (emulsifies fat in small intestine)

GERD

• Gastroesophageal reflux disease

Nutrient Storage Systems

• Fat: adipose tissue
• CHO: glycogen in liver and muscles
• Minerals: bones (calcium, phosphorus)

Alcohol Consideration

• Depressant

Alcohol Absorption

• Stomach and small intestine (80%)

Alcohol Metabolism Location

• Liver (80% via alcohol dehydrogenase (ADH)), 10% MEOS

MEOS

• Microsomal ethanol-oxidizing system (chain of enzymes that break down alcohol).

Alcohol's Effects on Bodily Functions

• Slows nerve signals
• Judgement
• Muscle control
• Heart and Breathing

Alcohol's Effects on Cells

• Dissolves lipids, penetrates cell's membranes readily
• Denatures cell proteins
• Fat accumulation in liver

Alcohol Increases Risk Of

• High blood pressure
• Dementia
• Mouth, liver, breast cancers
• Muscle deterioration
• Thiamin deficiency (Wernicke-Korsakoff syndrome)

Wheat Kernel

• 4 Parts (Germ, endosperm, bran, husk).

Refined

• Removal of bran, germ

Monosaccharides

• Glucose, fructose, galactose

Disaccharides

• Sucrose (fructose + glucose), lactose (galactose + glucose), maltose (glucose + glucose)

DRI Recommendation for Fiber

• 25g

DRI Recommendation for Sugar

• Less than 25% of calories from sugar

Starch

• Storage of glucose in plants (branched or unbranched), insoluble

Water Soluble Fiber Includes

• Gums, mucilage, pectin, psyllium, some hemicellulose

Water Soluble Fiber Aids In

• Lowering blood cholesterol
• Slowing glucose absorption
• Reducing heart and diabetes risk

Water Insoluble Fiber Includes

• Cellulose, lignin, some hemicellulose

Water Insoluble Fiber Aids In

• Increasing bulk
• Reducing diverticular disease, hemorrhoids, appendicitis

Small Intestine in CHO Digestion

• Enzymes (disaccharides -> monosaccharides)
• Pancreatic amylase (starches -> disaccharides)
• Monosaccharides -> liver -> glucose

CHO Digestion/Glucose Conversion Occurs In

• Small intestine (monosaccharides are converted to glucose)

Type 1 vs Type 2 Diabetes

• Type 1: autoimmune destruction of insulin-producing cells (little to no insulin produced)
• Type 2: cells become resistant to insulin (90% of cases)

Postprandial CHO Digestion

• Blood sugar increases after consumption
• Amount of increase reflects consumed amount, rate of digestion, glucose entry into blood stream, and glucose uptake rates by body cells.

Type 2 Diabetes Increases Risk Of

• Cardiovascular disease
• Kidney disease

Sugar Alcohols

• Sorbitol, xylitol, malitol

Artificial Sweeteners

• Aspartame, sucralose, acesulfame-k

Lactose Intolerance vs Milk Allergy

• Lactose intolerance: lack of lactase enzyme;
• Milk allergy: immune response to milk protein