NutritionWhat should my diet look like?

Old Food Guide Pyramid

One Size Fits All : (

MyPyramid.gov

• Developed by USDA• Personal guide to

healthy eating & physical activity

• Based on age, gender, activity level

• How does this pyramid compare to the old Food Guide Pyramid?

Anatomy of MyPyramidActivity: • Importance of daily

physical activity• At least 30 min. / day• 60 min. / day of

moderate to intense activity more beneficial

Moderation:• Narrowing of each

food group• Base represents

nutrient rich food w/ essential vitamins and minerals & fewer calories

• Top represents foods containing more added sugars & solid fats

Proportionality:• Different widths of food

groups• Widths suggest how much

food should be eaten from each group

Variety:• 6 color bands

representing 5 food groups & oils

• Food from all groups are needed for healthy nutrition

Personalization & Gradual Improvement:• Small steps everyday for YOU!!!

• Orange = Grains• Green = Vegetables• Red = Fruits• Yellow = Healthy

Fats/Oils• Blue = Dairy• Purple = Meat &

Beans

MyPyramid.gov

What Are YOUR Caloric Needs?

• Use MyPyramid.gov to discover YOUR needs– Individual food plan for caloric needs

– Tract diet & physical activity for up to 1 year

– Detailed info on each food group’s serving sizes, nutrients, & health benefits

– Info for special populations (i.e. pregnant, overweight, elderly, children)

6 Categories of Nutrients• Carbohydrates (CHO)• Lipids (Fats)• Proteins• Vitamins• Minerals• Water

Macronutrients

Micronutrients

Division of Total Daily Caloric (kcal) Intake

• CHO: 50-60%• Fat: 25-30% or less• Protein: 10-20%

– (0.8 grams per kg of body weight)

Carbohydrate2 Hydrogen for each Oxygen

C6H12O6

Glucose = simplest form of sugar

A Sugar is a Sugar is a….

•Glucose•Dextrose•Fructose•Lactose•Maltose•Sucrose

•Granulated sugar

•Confectioner’ sugar•Brown sugar•Corn syrup•Honey

•Invert sugar•Maple syrup•Molasses•Mannitol•Sorbitol•Sorghum

Categories of Carbohydrates

• Monosaccharides (glucose, fructose, galactose)

• Disaccharides (sucrose, maltose, lactose)

• Polysaccharides (starch, fiber, glycogen)

Monosaccharides = Simple Sugar Units• Glucose - Blood Sugar

– Found in fruits & vegetables– Used for:

• Cell energy• Stored as glycogen in muscles & liver• Converted to fat for energy storage

• Fructose - “Fruit Sugar”– Found in fruit, honey, corn syrup

• Galactose– Found as part of lactose in milk

Disaccharides = 2 Monosaccharides

Monosaccharides & Disaccharides = Simple Sugars

Sucrose = Glucose + Fructose (brown sugar; 25% of sugar intake)

Lactose = Glucose + Galactose (milk sugar; least sweet)

Maltose = Glucose + Glucose (honey)

50% of average American dietary CHO intake = simple sugars

Polysaccharides = 3 or more simple sugars combine

• Plant Polysaccharides:– Starch

• Peas, seeds, corn, grains, cereals, potatoes, roots

– Cellulose• Fiber (technically not a nutrient – resistant to digestion)

– Water-insoluble– Water-soluble– ***Recommended fiber intake = 20-35 g per day

Dietary Fiber

• Water-Soluble Fiber – Depress synthesis & absorption of cholesterol in gut– Bind existing cholesterol to facilitate excretion in feces– Ex: pectin & guar gum in oats, beans, peas, carrots, fruits

• Water-Insoluble Fiber – Hold water & give bulk to food residues in small intestine

increasing stool weight/volume– Ex: cellulose, hemicellulose, lignins, pectins in brown rice,

corn, & wheat bran• Health Implications of Fiber:

– Colorectal cancer, diabetes, intestinal disorders (stool issues), cholesterol effects

Dietary Fiber• Average American eats 12 g of fiber / day

• Recommended Intake of Fiber = 20-35 g / day– Insoluble to soluble = 3:1

• Guess who has the highest incidence of colorectal cancer?

Polysaccharides = 3 or more simple sugars combine

• Animal Polysaccharides:– Glycogen

• Ranges in size from few hundred to thousands of glucose molecules liked together like sausage links

• Storage form of glucose• 375-475 g stored in body (liver, muscle, kidney)• Can be modified by diet & exercise• Most important energy fuel

Functions of CHO

• Important Energy Source

• Protein Sparer

• Metabolic Primer

• Central Nervous System Fuel

Source of CHO• Dairy• Fruits• Cereals• Breads• Pasta

Big Issue = Simple vs. Complex CHO

Preferred Choice=

Complex CHO

BUT…

Recommended CHO Intake

• Percent of daily total caloric intake = 50-60%

• So, if I eat 1200 kcal / day, 600 – 700 kcal should be from carbohydrates

• 1 gram of CHO = 4 kcalCalorie (kcal) =

unit of heat used to express energy

value of food

What are the Fates of Blood Glucose?

Blood Glucose

Muscle Glycogen

Adipose Tissue

Used for Energy

Kidney Excretion

Liver Glycogen

Nature of Lipids

• Same structural elements as CHO but linking of atoms is different (C, H, & O)

• The H to O2 ratio is typically 18.3:1– (CHO is 2:1)

• Found in both plants & animals• 3 kinds of lipids

– Simple, Compound, & Derived• Generally greasy to touch & insoluble in water

Kinds of Lipids – Simple Fats

• aka Neutral Fats• Triglyceride

– Most common & plentiful fat in body

– More than 95% of body fat is triglyceride (primary storage form)

– Composed of 2 different atom clusters

• Glycerol (3 carbon sugar) + 3 Fatty Acids

Simple Fats:

Fatty Acids• Give each fat unique qualities of flavor & texture• Differ in:

– Length of carbon chain– Bonding of carbon atoms & arrangement of

hydrogens along carbon chain• 3 Kinds of Fatty Acids:

– Saturated– Unsaturated– Essential

Saturated Fatty Acid• A saturated fatty

acid contains only single bonds between C atoms; all remaining bonds attach to hydrogen– The fatty acid

molecule holds as many H+ atoms as possible - thus the term saturated

• Found primarily in animal products:– Beef– Lamb– Pork– Chicken– Egg yolk– Cream, milk, butter, cheese (Dairy)– Coconut and palm oil– Vegetable shortening– Hydrogenated butter

Saturated Fatty Acids

• Contain one or more double bonds along the main C chain - the fatty acid is unsaturated with respect to H+

• Mono-unsaturated: 1 double bond (olive, canola, and peanut oil)

• Poly-unsaturated: 2 or more double bonds (safflower, sunflower, soybean, corn oil)

Unsaturated Fatty Acids

Unsaturated Fatty Acids

Each double bond takes the

place of 2 hydrogen

atoms

Saturated vs Unsaturated Fat

Regardless of the degree of saturation, all

lipids have essentially the

same number of calories per unit

weight.

1 g of fat = 9 kcal

Essential Fatty Acids

• Polyunsaturated fatty acids– Linoleic acid = Omega-6 fatty acid

• Vegetable oil, corn oil, sunflower oil, peanut oil

– Alpha-linolenic acid = Omega-3 fatty acid• Green leafy vegetables, canola oil, soy products, fish

• Must be consumed from food/diet• Serve as precursors of other fatty acids which

body can not synthesize

Eicosapentaenoic acid (fish oil)

–Found in oils of shell fish, cold-water tuna, herring, sardines, mackerel & sea mammals

• CHD protective • Prevents blood clot formation on arterial walls• Lowers blood pressure• Increases plasma HDL• Decreases LCL cholesterol

Omega-3 Fatty Acids

Eat fish – 10 ounces / week!!!

Hydrogenation• Oils exist as liquids & contain unsaturated fatty acids• Hydrogenation changes oils to semi-solid fat

– Bubbles liquid hydrogen into vegetable oil w/ mineral catalyst nickel

• Reduces unsaturated fatty acids’ bonds from double bonds to single bonds– More hydrogen attach to carbons

• Firmer fat results b/c hydrogen increases lipid’s melting temp.• Hydrogenated oil behaves like a saturated fat

Trans Fatty Acids• Hydrogenation of vegetable oils

– Unsaturated corn, soybean & sunflower oil

• Results when one of the H+ moves from its naturally occurring position to the opposite side of the double bond– 17-25% in margarine– 7% in butter– Possible links to heart disease

• (30,000 deaths / year)

Kinds of Fat - Derived Lipids• Cholesterol

– Exists only in animal tissue– No FFA but shares similar characteristics– Exists as endogenous cholesterol

• 0.5 - 2.0 g/d production• More forms with high saturated diets

– Functions include: building plasma membranes, synthesizing Vit D, adrenal gland hormones and sex hormones (estrogen, androgen, progesterone), bile; tissue and organ formation during fetal development.

Recommended Cholesterol Intake• 300 mg (1/100 oz) / day or LESS!!!

• 100 kCal per 1000 kCal ingested– 1 cup skim milk = 4 mg– 1 cup whole milk = 33 mg– 3 oz beef = 680 mg

Fat in the Diet• Average American now consumes 15% of total kCal

(>50 lbs) of saturated fat per year, most of which is animal in origin

• 25-30% of total daily kcal intake should be fat– More unsaturated– Less saturated– Try to avoid trans fat, hydrogenated fats

Fat in the Diet

Roles of Fat 1. Energy source and reserve

-9 kCal/g2. Protection and insulation3. Vitamin carrier4. Satiety

Protein• Most abundant

organic compound in body

• Found in living matter

• Growth & repair of body tissue

Protein Organization• Chemical organization similar to fats & CHO,

except protein also contains nitrogen

• Nitrogen = 16% of protein molecule

• Basic units – “building blocks” – of protein are Amino Acids (AA)

Proteins & Amino Acids (AA)• Amino Radical – NH2

• Organic Acid Radical – COOH• Side Chain – R

– Determines differences between amino acids

Amine + Acid = Amino Acid

23 Different Amino Acids

Essential/Nonessential AAEssential (cannot be synthesized by the body and be obtained from food)

HistidineIsoleucineLysineMethioninePhenylalanineThreonineTryptophanValine

Nonessential (made in the body)

AlanineArginineAsparagineCysteineGlutamic acidGlutamineGlycineProlineSerineTyrosine

Proteins in Foods• Proteins can be found in both animals and plants

• Nothing “better” about an amino acid from animal compared to same amino acid from plant origin

• Proteins in food classified as complete or incomplete depending on amino acid content

Proteins in Foods

• Complete aka High-Quality Protein– Contain all essential AA in quality & correct proportion to

maintain nitrogen balance & promote normal growth– Usually animal products (eggs, milk, meat, fish, poultry)

• Incomplete aka Lower-Quality Protein– Lacks one or more of the essential AA– Usually plant products (nuts, lima beans, lentils)

Complimentary Function of Proteins• All essential amino acids can be consumed by eating

variety of vegetable foods

• Example: Grains & legumes– Grains lack AA lysine which legumes have– Legumes lack AA methionine which grains have– Tortillas & beans; rice & beans; rice & lentils; rice & peas;

peanuts & wheat bread

• B/c large amounts of these foods must be eaten to obtain required amount of AA, people eat animal products

Protein RDA0.8 - 0.9 grams/kg BW

Examples–50 kg (110 lb) person = 40 g (1.4 oz)–85 kg (187 lb) person = 68 g (2.4 oz)

Your Protein Needs

• Determine ideal body weight• Determine protein needs:

– Older Teen – 0.9 g / kg BW– Adult – 0.8 g / kg BW– Adult Athlete – 1.1 – 1.6 g / kg BW– Pregnant – add 10 g– Lactating – add 15 g for 1st 6 months & 12 g after

• Body Weight X Need = Protein Requirement

Functions of Proteins

• Anabolism• Structural proteins• Enzymes• DNA, RNA• Blood Plasma• Vitamin precursor• 1g = 5.65 kCal

– Reduces to 4 kcal

FATE OF AMINO ACIDS

• Gluconeogeneis - 18 AA serve as a source for glucose synthesis

• Energy Source - Oxidized for energy in Krebs cycle

• Fat Synthesis - All AA provide a potential source for fat synthesis

Semivegetarian - avoids only certain kinds of meat, fish, poultryLacto-ovo vegetarian - avoids eating any animal flesh, but uses dairy products and eggsLacto-vegetarian - avoids eating animal flesh and eggs, but uses dairy productsVegan - avoids all foods of animal origin, even dairy products and eggsMacrobiotic Vegetarian - ten dietary stages; Fruitarian- includes only fruit, nuts, honey and olive oil

Nonprotein Consumers

WHAT ARE VITAMINS?

• Essential organic substances • Needed in MINUTE amounts by body • Perform specific metabolic functions

• When vitamin is synthesized from existing chemicals in body the ingredient to make the conversion are called pro-vitamins– Ex: Carotine – Vitamin A

Where do Vitamins Come From?

• All vitamins found in green leaves & roots of plants (photosynthesis)

• Exception: Vitamin B12 – found only in animals

• Man cannot synthesize Vitamin C & most of fat soluble vitamins

FUNCTIONS OF VITAMINS• essential links and regulators in metabolism• tissue synthesis

2 Types of Vitamins

• Fat-Soluble– A (Retinol)– D (Cholecaciferol)– E (Tocopherol)– K (Menadione)

• Water-Soluble– C (Ascorbic Acid)– Thiamin– Riboflavin– Niacin– B-6 (Pyridoxine)– Pantothenic Acid– Biotin– Folate– B-12

FAT SOLUBLE VITAMINS

A, D, E, K–Daily ingestion unnecessary –Stored in the liver, fat cells and

subcutaneously–No mechanism to leave the body–Can be toxic in excess

VITAMIN ARDA = 0.8 - 1.0 mg

• Functions– Constituent of visual pigment– Antioxidants– Maintenance of epithelial tissues

• Food Sources– Yellow-orange vegetables– Orange fruits– Dark-green leafy vegetables

VITAMIN D

RDA = .005 - .01 mg• Functions

– Promote growth & mineralization of bones– Increases absorption of calcium

• Food Sources– Dairy products– Cod-liver oil– Eggs– (Non-food source) Sunlight!!!

VITAMIN D Deficiency

• Rickets = vitamin D deficiency disease of children

• Osteomalacia = vitamin D deficiency in adults (softening of bones, making them brittle)

VITAMIN E• A vitamin in search of a disease!

“no known evidence of dietary deficiency of vitamin E in humans”

RDA = 15 mg

• Functions– Anti-oxidant to prevent cell membrane

damage• Food Sources

– Seeds– Green leafy vegetables– Margarines & shortenings

VITAMIN K

• Functions– Blood clotting– Formation of bone

• Food sources– Green vegetables– Liver– Egg yolks

RDA = .06-.08 mg

Water Soluble Vitamins• Vitamin C & B-complex group

– Transported throughout water medium of the body

– Not stored in body– Voided in urine– Must be consumed regularly - daily

B Vitamins• B vitamins act primarily as

coenzymes• Work as catalysts• Function in energy-producing

metabolic reactions• Includes:

– Thiamin 1.1 -1.2 mg/day– Riboflavin 1.1-1.3 mg/day– Niacin 14-16 mg/day– B6 1.3-1.7 mg/day– Folate 0.2 mg/day– B12 0.002 mg/day

VITAMIN C

• Increases absorption of iron• Influences serum cholesterol• Affects immune system• Affects synthesis of collagen• Affects drug metabolism• Protects DNA in sperm• Maintains intercellular matrix of cartilage, bone, &

dentine

RDA = 75-90 mg

Minerals• 4% of body mass

composed of 22 metallic elements called minerals

• Important minerals found in enzymes, hormones, & vitamins

• Classified as major or minor

Major and Minor Minerals

• Minor Minerals(intake needed < 100 mg/day)

– iron– zinc– copper– selenium– iodine– fluorine– chromium– molybdenum– manganese

• Major Minerals• (intake needed >100 mg/day)

– sodium– potassium– calcium– phosphorus– magnesium– sulfur– chlorine

Bioavailability of Minerals

• Extent that mineral is absorbed by body & made available for its biologic functions

• Affected by:– Vitamin-Mineral Interaction

• Synergism in consuming some vitamins & minerals together

• Example: calcium & vitamin D

– Fiber-Mineral Interaction• Example: Too much fiber decreases absorption of

calcium, zinc, magnesium, iron

Where Do Minerals Come From?• Occur freely in nature (rivers, lakes, oceans, topsoil,

under earth’s surface)

• Found in root systems of plants and in body structures of animals that consume plants and water

• Best sources of minerals are animal products (because they are more concentrated in animal tissues than in plants)

Functions of Minerals

• Provide structure in formation of bones & teeth

• Maintain normal heart rhythm, muscle contractility, nerve conduction, & acid-base balance of body fluids

• Regulatory role in cellular metabolism

• Part of enzymes & hormones that modify & regulate cellular activity

• Involved in catabolism & anabolism of nutrients

• Body’s most abundant mineral (1.5 to 2.0% of body mass; 1400 g)

• Ca combines with P to form hydroxyapatite, the crystalline structure of bones and teeth

• Ionized, Ca serves these functions:• Muscle contraction• Transmission nerve impulses• Activation of enzymes• Blood clotting• Fluid movement across membranes

Calcium

Osteoporosis• When calcium is deficient, bones

“give up” their calcium to try & restore deficit

• Bones become hollow or porous leading to breaks & fractures

• Hormone estrogen linked to osteoporosis– b/c estrogen enhances Ca

absorption, a decrease in estrogen no longer offers a protective effect

Osteoporosis:Bone Disease of Epidemic Proportions

• 1.5 million fractures yearly• 500,000 spinal fractures• 230,000 hip fractures

• Each year, 1.3 million osteoporetic women will fracture one or more of their bones

• About 1 of 6 older men & 1 of 3 older women will sustain hip fractures (death will occur in 20%)

• Often, x-rays don’t detect the disease until bone loss reaches 30 to 50% of its total mineral content!

Progressive Disease

• 30-50% bone loss by age 70 y

• Shrinkage of spinal vertebrae

Who Gets the Disease?

• By age 50:– Men lose about 0.4% bone each year– In women, the loss is about 0.8% starting at age 35

(double the loss 15 years sooner!)

• During menopause, bone loss accelerates to between 1% to 3% each year. Thus, by age 60, a woman can lose about 15% of her bone mass, and by age 70, bone loss can be as much as 30%

Where Does The Bone Loss Occur?• Most occurs in the vertebrae

– person shrinks in stature by up to 6 inches from age 45-50 to age 70

• The “spongy” bone (trabecular bone) loses its mineral content, causing the bone to crumble. The inside of the bone becomes honeycombed (like a beehive) and porous

CALCIUM AND EXERCISE HELPS

• Exercise -weight bearing help– weight training important for “bone fitness”

• 1200-1500 mg Calcium daily• Sardines, pink salmon, ricotta

cheese, dried figs• Calcium carbonate & calcium

citrate can help• Meat, salt, coffee, alcohol

inhibit Ca absorption

• Excessive intake increases fluid volume and peripheral vascular resistance– sodium-induced hypertension (occurs in 1/3 of individuals

with hypertension in U.S. and Japan)

• Recommended level = 1100 to 3300 mg/day – average in U.S = 3000 to 7000 mg/day– amount actually needed = 500 mg/day

• Sodium plentiful in table salt, MSG, soy sauce, condiments, canned foods, baking soda, baking powder

Sodium: How Much is Enough?

Vitamins and minerals do not appear to have any ergogenic value in amounts beyond the

RDA. Amounts greater than RDA probably does

not improve performance.

Vitamins & Minerals: The Bottom Line