HED 235 - Nutrition - Exam 2 Study Guide

Unit 8 – Calories! Food, Energy, and Energy Balance

3 Types of energy-requiring processes:

1)   Basal Metabolism – Body’s life support ~ weight * 10 (female) OR * 11 (male)

2)   Physical Activity – Level of physical activity à Active (4+ hrs exercise) = 75% BMR,  Average (2-4 hrs light activity) = 50% BMR, Inactive (<2 hrs activity) =30% BMR

3)   Dietary Thermogenesis – Energy for digestion, absorption, and food storage = 0.10(BMR+Physical activity)

Total calories need = (BMR + (0.3, 0.5, or 0.75 * BMR) + (0.10 * BMR+physical activity))

Food energies:

·      Carbs = 4 calories/g

·      Proteins = 4 calories/g

·      Fats = 9 calories/g

·      Alcohol = 7 calories/g

·      Fiber = 2 calories/g

Energy density (calories-density) = Calories of food/Food in grams à Calories/grams

Energy balance:

·      Calories consumed > calories used = weight GAIN

·      Calories consumed < calories used = weight LOSS

·      Calories consumed = calories used = balance, weight maintenance

Unit 12 – Useful Facts about Sugars, Starches, and Fiber

Carbohydrates – sugars à Major source of energy (~ 45-65%)

·      Simple sugars –glucose, fructose, galactose (Must be listed in order of weight in labels) à Problem: Provide ONLY calories, Low in nutrients; tooth decay

§  Monosaccharides

o   Glucose – Only simple sugar can use to form energy. Excess stored as fat and glycogen (Only animals).

o   Fructose

o   Galactose

§  Disaccharides

o   Sucrose (glucose + fructose)

o   Maltose (glucose + glucose)

o   Lactose (glucose + galactose)

·      Alcohol sugars – simple sugars w/ alcohol group

§  Ex: Xylitol, mannitol, sorbitol

§  Does NOT promote tooth decay

·      Artificial Sweetener Facts

§  Not significant sources of energy/nutrients

§  Used as sweetening agents

§  Does NOT promote tooth decay

§  Ex: Saccharin, aspartame, sucralose, acesulfame potassium, neotame, rebiana

·      Complex carbohydrates (starches)

§  Polysaccharides: Many molecules of monosaccharides (starch, glycogen, dietary fiber)

§  Oligosaccharides: 3 – 10 monosaccharides

·      Fiber

§  Functional fiber: Specific type of nondigestible carbs that benefit health (psyllium, pectin, gels, gums) à Fullness, slows glucose absorption, prevents constipation, decrease fat & cholesterol absorption.

§  Dietary fiber: Naturally occurring, intact forms of nondigestible fiber in plants and “woody” plant cell walls (contains nutrients & other plant substances)

§  Total fiber: Sum of functional & dietary fiber (Recommend daily intake of fiber).

o   Soluble fibers – Combine chemically with water

o   Insoluble fibers – Do NOT combine chemically with water

Glycemic index: How much blood glucose is raised by 50g portion of carbohydrate compared to glucose/white bread.

- Low glycemic index carbohydrates: (Fructose, xylitol, hummus, apples)

·      Improve blood glucose control

·      Reduce elevated blood cholesterol & triglycerides

·      Increase HDL

·      Reduce risk of DM2, cancer & heart disease

- High glycemic index carbohydrates: (Glucose, white bread, baked potatoes, jelly beans)

·      Tooth Decay (cavities – disintegration of teeth b/c acids produced by bacteria

·      Stickiness & frequent consumption of sugary/starchy food increases tooth decay

·      Baby bottle caries – develop when infants/children fall a sleep while sucking bottle

Unit 15 – Proteins & Amino Acids

Protein = Essential component of all living matter composed of polymer chains of amino acids linked by peptide bonds.

FUNCT:

v Structural material in muscles, CT, organs, and hemoglobin (RBC)

v Basic component of enzymes, hormones, + other chemicals

v Mains & repairs protein containing tissues (fibrin)

v Serves as an energy source (4 calories/g)

·      ALL proteins in body are continually broken down & rebuilt.

·      Does NOT have storage form in body.

·      154 lb man contains ~ 124 lb protein (50% muscle)

·      High protein diets usually HIGH in FAT and LOW in FIBER

·      “Lean” meats have varying levels of fat: Hamburger 90% lean = 45% fat, Baked chicken breast no skin = 19% fat.

Amino Acids – 20 common

·      Order of Amino acids determined by DNA (Primary structure)

·      Sub-structures formed among amino acid chains (Secondary structure)

·      Chains of amino acids can form 3D shapes (Tertiary structure)

·      3D structure consisting of the aggregation of 2+ individual polypeptide chains (subunits) that operate as a single functional unit (Quaternary structure)

Ø  Essential amino acids – CANNOT be synthesized in enough in body, from diet

o   Phenylalanine

o   Valine

o   Threonine

o   Tryptophan

o   Isoleucine

o   Methionine

o   Histidine

o   Leucine

o   Lysine

Ø  Nonessential amino acids – Produced by humans from components of diet

o   Alanine

o   Arginine

o   Asparagine

o   Aspartic acid

o   Cysteine

o   Glutamic acid

o   Glutamine

o   Glycine

o   Proline

o   Serine

o   Tyrosine

Complete Proteins = Contains all essential amino acids in amounts needed to support growth (In animal products such as meat, milk, eggs).

Incomplete Proteins = Deficient in one/more essential amino acids (Plants – usually different complements combined to make up)

v Amino acid supplements can lead to adverse effects (eg. Disrupt protein protection)

v TO GROW MUSCLE – Resistance training, then high quality protein foods.

Protein deficiency can occur by itself/with other calorie & nutrient deficiencies.

- Kwashiokor = protein-energy malnutrition à causes swelling, fatty liver, poor appetite NOT corrected by protein intake.

EXCESS PROTEIN: > 45% calories form protein (nausea, weakness, diarrhea)

High protein diets à weak bones, kidney stones, cancer, hear disease, obesity

Unit 18 – Fats and Cholesterol in Health

Fats = subcategory of lipids (Compounds insoluble in water eg. Triglycerides, oils, cholesterol, essential fatty acids, sat/unsat fats)

Recommended – 20-35% of total calories from fat

FUNCT:

v Energy source ~ 1 lb of body fat = 3500 calories (9 calories/g)

v Carriers of fat-soluble nutrients (essential fatty acids, fat soluble vitamins DEKA)

v Cushion & protect internal organs

v Insulation against cold

v Increase flavor and palatability of food

v Contribute to sensation of feeling full

v Components of cell membranes, vitamin D and sex hormones

✪ Essential fatty acids = linoleic acid + alpha-linolenic acid

Ø  Linoleic acid (Men 5g/day, Women 12 g/day)

§  Ω-6 fatty acid

§  Component of all cell membranes

§  Required for growth, skin, reproductive system

§  Regulation of BP, clotting – inflammatory

§  In sunflower, safflower, corn & soybean oils

Ø  Alpha-linolenic acid (Men 1.6 g/day, Women 1.1 g/day)

§  Ω-3 fatty acid

§  Compoent of all cell membranes

§  OPPOSITE effect on linoleic acid w/ BP & clotting – Anti-inflammatory

§  In walnuts, dark green leafy vegetables, flaxseed, canola & soybean oils

Other Ω-3 fatty acids EPA & DHA – Found in fish and shellfish (common fish oil additive)

Ø  Eicosapentaenoic acid (EPA)

§  Precursor compounds used for blood clotting & blood pressure regulation

§  Limits damage from inflammatory & oxidative reactions

Ø  Docosahexaenoic acid (DHA)

§  Needed for brain & eye formation

Types of fat:

      I.         Glycerides

A.     Monoglycerides

B.     Diglycerides

C.     Triglycerides (98% of fat intake, most of body’s fat storage, used for energy and maintenance)

    II.         Saturation (Unsat/sat)

A.     Saturated (Max # of H atoms, (s) @ room temp, animal products)

B.     Unsaturated fats

1)   Cis form – zis same side (most common, naturally occurring form of unsat fatty acid)

2)   Trans form – opposite sides (increase cholesterol lvls, heart risk, - 2.2 g/day

a.     Monounsaturated – 1 double bond

b.     Polyunsaturated – 2+ double bonds

Hydrogenation: unsaturated fats à saturated fats, (l) à (s) (used to extend shelf life of processed foods)

Cholesterol: Organic molecule, a sterol, a type of lipid. Biosynthesized by all animal cells and is an essential structural component of animal cell membranes.
FUNCT:

v In all cell membranes – flexible lipid bilayer

v Major component of nerves & brain

v Needed to produce estrogen, testosterone, vitamin D

v CANNOT be used for energy

Labeling

·      Specify fat, saturated fat, trans fat, and cholesterol fat

Types of fat more important than amount:

·      Good fat = DHA, EPA, Unsaturated fats, Alpha-linoleic acid

·      Bad fat = Trans, saturated fats, cholesterol (rec <200mg/day)

Unit 20 – Vitamins and Your Health

Vitamins – Chemical substances that perform specific functions in the body, essential nutrients

·      Water soluble (B-complex, C)

§  Thiamin (B₁)

§  Riboflavin (B₂)

§  Niacin (B₃)

§  Vitamin B₆ (pyridoxine)

§  Folate (folacin, folic acid)

§  Vitamin B₁₂ (cyanocobalamin)

§  Biotin

§  Panthothenic acid (pantothenate)

§  Choline

§  Vitamin C (ascorbic acid)

v ONLY vitamin B12 stored in body all other water sol vitamins, deficient in weeks if NOT consumed

v Niacin, B6, choline, and Vitamin C can effects if over consumed

·      Fat soluble (DEKA)

§  Vitamin D (1,25 dihydroxy-cholecalciferol)

§  Vitamin E (tocopherol)

§  Vitamin K (phylloquinone, menaquinone)

§  Vitamin A (retinol, provitamin = ß-carotene)

v Stored in body fat, liver – allows deficiencies to take longer to develop, excess build up in fat

FUNCTS: Depends on vitamin, many coenzymes, antioxidants (vita C, E, ß-carotene)

Some items misinformed OR exaggerated (Bogus vitamins)

✖  Bioflavonoids (vitamin P)

✖  Coenzyme Q₁₀

✖  Gerovital H-3

✖  Hesperdin

✖  Inositol

✖  Laetrile (vitamin B₁₇)

✖  Lecithin

✖  Lipoic acid

✖  Nucleic acids

✖  Pangamic acid (vitamin B₁₅)

✖  Para-amino benzoic acid (PABA)

✖  Provitamin B5 complex

✖  Rutin

NAME	Adequate Intake	FUNCT	Deficiency	Overdose (OD)
Thiamin  (Vitamin B1)	♂ 1.2mg ♀ 1.1mg	Release energy from carbs ingested; facilitates growth & muscle; normal appetite	Fatigue, weakness, nerve disorders, apathy impaired growth, swelling, heart irregularity (beriberi)	High intakes rapidly excreted by kidneys.
Riboflavin (vitamin B2)	♂ 1.3mg ♀ 1.1mg	Help capture & use energy released from carbs, proteins, fats; aids in cell division; promotes growth & tissue repair; normal vision	Reddened lips, cracks at corners of mouth, fatigue	NONE
Niacin (Vitamin B3)	♂ 16mg ♀ 14mg	Helps capture & use energy released from carbs, proteins, fats; assists in body fats; maintain normal nervous system	Skin disorders, nervous & mental disorders, diarrhea, indigestion, fatigue (Pellagra)	Flushing headache, cramps, tachy, nausea, diarrhea, decreased liver funct
Pyridoxine (Vitamin B6)	♂ 1.3mg ♀ 1.3mg	Needed for rxn in building proteins & protein tissues; assists tryptophan à niacin convert; promotes normal nervous system	Irritability, depression, convulsions, twitching, muscular weakness, dermatitis near eyes, anemia, kidney stones	Bone pain, loss of feeling in fingers & toes, muscular weakness, numbness, loss of balance (mimicking MS)
Folate (folacin, folic acid)	♂ 400mg ♀ 400mg	Needed for rxns using utilize amino acids for protein tissue formation; promotes normal formation of RBC	Megaloblastic anemia, diarrhea, red sore tongue; neural tube defects, elevated homocysteine	May cover B12 deficiency
Cyanocobalamin (Vitamin B12)	♂ 2.4mcg ♀ 2.4mcg	Helps maintain nerve tissues; aids in rxns that build up protein tissues; needed for normal RBC	Neurological disorders, tingling, brain degeneration, pernicious anemia	NONE, may cause temp heightening energy
Biotin	♂ 30 mcg ♀ 30 mcg	Needed to manufacture fats, proteins and glycogen	Seizures; vision problems; muscular weakness; hearing loss	NONE
Pantothenic acid	♂ 5 mg ♀ 5 mg	Needed to release energy from fat & carbs	Fatigue, sleep problems, vomiting, nausea	NONE
Vitamin C (ascorbic acid)	♂ 90 mg ♀ 75 mg	Making collagen; help fight infection, repair wounds; antioxidant; enhance iron absorption	Bleeding and easy bruising, slow recovery from infections and poor wound healing, fatigue, depression	Intake of 1g or more/day causes nausea, cramps, diarrhea, increase kidney stone risk
Choline	♂ 550 mg ♀ 425 mg	Structural & signaling component of membranes; needed for normal development of memory & attention; transport of fat & cholesterol	Fatty liver, infertility, HTN	Hypotension, sweating, diarrhea, fishy body odor, liver damage
Retinol (vitamin A)	♂ 900 mg ♀ 700 mg	Need for formation & maintenance of mucous membranes, skin, and bone; vision in dim light	Increase infection risk, impaired vision	> 500,000IU and >50,000IU/day nausea, irritability, blurred vision, weakness, headache, skull pressure, liver damage, hair loss, dry skin
ß-carotene	N/A	Acts as antioxidant	Similar to vitamin A	>12mg/day may turn skin yellow-orange
Vitamin E (alpha-tocapherol)	♂ 15 mg ♀ 15 mg	Acts as antioxidant; reduces ability of LDL cholesterol	Muscle loss, nerve damage, anemia, weakness	>800IU/day may increase bleeding, Avoid supplement w/ anticoags
Vitamin D	♂ 5 mcg ♀ 5 mcg	Absorption of Ca and P for use in bone formation, nerve and muscle activity, stops inflammation	Weak, deformed bones, loss of Ca from bones, increase cardio-vascular risk	Mental retardation in children, abnormal bone growth, nausea, diarrhea, weight loss, Ca deposits in organs >10,000IU/day toxic
Vitamin K	♂ 120 mcg ♀ 90 mcg	Essential component of blood clotting mechanisms; aids incorporation of Ca into bones	Bleeding, bruises, decreased Ca in bones, Rate deficiency	Toxicity only issue when synthetics are taken à may cause liver disease