nutrition study guide for exam 2

proteins provide how many calories per gram

4

AMDR of protein

10-35% of daily calories

general recommendation for calories per kilo gram

0.8 g protein per kg body weight

recommendation for calories per gram for active people

1.2-2.0 g protein per kg body weight

70 kg person

70 × 0.8 = 56 g protein/day

building blocks for protein

• amino acids

• 20 total amino acids

basic chemical structure for amino acids

• carbon

• amino group (NH2)

• carboxyl group (COOH)

• hydrogen (H)

• R-Group (determines function)

amino acids are joined by

peptide bonds

types of peptide bonds

• dipeptide= 2 amino acids

• tripeptide= 3 amino acids

• polypeptide= many amino acids

digestive and absorption of protein

1. stomach

   1. acid denatures protein

   2. pepsin begins breakdown

2. small intestine

   1. pancreatic enzymes

      1. chymotrypsin

      2. trypsin

      3. carboxypeptidase

      4. break into smaller peptides

3. absorption

   1. amino acids absorbed into blood stream

   2. transported to liver- then body tissues

key protein digesting enzymes

• pepsin

• trypsin

• chymotrypsin

• carboxypeptidase

essential amino acids (9)

must be obtained from diet

nonessential amino acids (11)

body can make them

branched chain amino acids

• leucine

• isoleucine

• valine

  • important for muscle repair and energy during exercise

denaturation

• protein loses its shape due to:

  • heat

  • acid

  • mechanical action

    • does not destroy nutritional value, just structure

what makes proteins unique

• proteins contain nitrogen

• carbs and fats do not

positive nitrogen balance

• intake> loss

• growth, pregnancy, muscle building

negative nitrogen balance

• loss> intake

• illness, starvation, injury

complete proteins

• contain all 9 essential amino acids

• ex. meat, fish, eggs, dairy, soy

incomplete proteins

• missing one or more essential amino acids

• ex. beans, grains, nuts

complementary proteins

• combine incomplete sources to make complete

• ex. rice, bean

nine essential amino acids

• histidine

• isoleucine

• leucine

• lysine

• methionine

• phenylalanine

• threonine

• tryptophan

• valine

why the body needs protein

• builds and repairs tissues

• makes

  • enzymes

  • hormones

  • antibodies

• maintains fluid and pH balance

• can provide energy if needed

what are enzymes

• proteins that speed up chemical reactions

• essential for digestion, metabolism, and cell function

animal protein food sources

• meat, poultry, fish, eggs, dairy

plant protein food sources

• beans, lentils, tofu, nuts, seeds, whole grains

kwashiorkor

• severe protein deficiency

• common in developing countries

symptoms of kwashiorkor

• swollen belly (edema)

• muscle wasting

• weak immune system

vegetarian

no meat

vegan

no animal products at all

benefits of vegan/ vegetarian

• lower risk of heart disease, obesity, type 2 diabetes

risks of vegan/vegetarian

• possible nutrient deficiencies if not planned well

nutrients that may be lacking in a vegetarian diet

• vitamin b12

• iron

• calcium

• vitamin d

• omega 3 fatty acids

• zinc

muscle protein synthesis

• process of building new muscle proteins

• stimulated by:

  • resistance exercise

  • protein intake

• important for:

  • muscle growth

  • recovery

sodium

• major nutrient

• AI= 1500 mg

• DV= 2300 mg

• sources

  • NaCl (salt)

  • processed/ packaged foods

  • restaurant foods

  • bread, pizza, sandwiches, soup

• major functions

  • electrolytes (fluid balance)

  • muscle/ nerve function

• raises blood pressure

potassium

• major nutrient

• DV= 4700 mg

• sources

  • fruits/veggies

  • potatoes

  • beans

  • milk products

• major function

  • electrolyte (fluid balance)

  • muscle/ nerve function

• lowers or normalizes blood pressure

chloride

• major nutrient

• sources

  • NaCl (salt)

• major functions

  • electrolyte (fluid balance)

  • nerve function

calcium

• major nutrient

• 1000 mg- 1200 mg for older adults

• sources

  • dairy products

  • plant based milks

  • tofu

  • green veggies

• major functions

  • bones

  • blood clotting

  • muscle/ nerve function

• deficiency

  • osteomalacia

  • osteoporosis

  • peak bone mass in teens/ 20s

• vitamin d helps absorb calcium

• most abundant mineral in body

• 99% stored in bones

phosphorus

• major nutrient

• sources

  • milk

  • cheese

  • meat

  • grains

• major functions

  • bones

  • teeth

  • dna and rna

  • atp and pcr (energy)

• 2nd most abundant mineral in the body

magnesium

• major nutrient

• sources

  • plant based (veggies, beans, whole grains)

• major function

  • bones

  • energy metabolism

  • enzymes

• stored in bones

sulfur

• major function

• sources

  • protein rich food

• major function

  • structure of amino acids

iron

• trace mineral

• sources

  • meat (heme)

  • grains and bones (non heme)

• major function

  • hemoglobin/ myoglobin in red blood cells to transport oxygen

• deficiency

  • iron

  • anemia (most common widespread mineral deficiency

• heme= absorbed much better

• non heme= poorly absorbed

• vitamin C improves absorption of non heme

• accidental poisoning in children

zinc

• trace mineral

• source

  • protein rich foods

  • whole grains

• main function

  • enzymes

  • shorten duration of colds (if taken within first 24 hours)

• may affect taste

copper

• trace mineral

• sources

  • protein rich foods

  • nuts

  • dark chocolate

• main function

  • enzymes

  • energy metabolism

  • protect cells (antioxidant)

manganese

• trace mineral

• sources

  • grains

  • nuts

  • veggies

• main function

  • energy metabolism

iodine

• trace mineral

• sources

  • iodized salt

• main function

  • thyroid hormones

  • function metabolism

• deficiency

  • goiter

selenium

• trace mineral

• sources

  • seafood

  • meats

  • grains

• main function

  • antioxidant

  • immunity

chromium

• trace mineral

• source

  • widespread

• main function

  • blood glucose regulation

  • insulin sensitivity

fluoride

• trace mineral

• source

  • toothpaste

  • mouthwash

  • flaunted water

  • tea

• main function

  • teeth

  • prevents cavities

• not in bottled water

functions of water

• transport: carries nutrients, oxygen, and waste in blood

• temperature regulation: sweating cools the body

• lubrication: cushions joints and tissues

• chemical reactions: needed for metabolism/ digestion

• maintains blood volume and pressure

• waste removal: urine removes toxins

inputs for water

• beverages

• foods

• metabolic water

outputs for water

• urine

• sweat

• breathing

• feces

hyponatremia

• blood sodium levels are too high

• usually caused by drinking too much water without electrolytes

symptoms of hyponatremia

• headache

• nausea

• confusion

• some seizures

how much water makes up human body

60%

how much water makes up muscles

70-75%

water intake recommendations

• men: 3.7 liters a day/ 125 oz

• women: 2.7 liters a day/ 91 oz

electrolytes

• minerals that carry an electric charge when dissolved in water

key electrolytes

• sodium (Na+)

• potassium (K+)

• chloride (Cl-)

functions of electrolytes

• fluid balance

• nerve signaling

• muscle contraction

two categories of minerals

• major minerals

• trace minerals

major minerals

• needed in large amounts

trace minerals

• needed in small amounts

bioavailability

• refers to how well a nutrient is absorbed and used by the body

example of bioavailability

• iron from meat (heme)= high bioavailability

• iron from plants (non heme) = low bioavailability

vitamin A

• fat soluble

• sources

  • animal products

• major functions

  • vision

  • immunity

  • cell differentiation

• deficiency

  • night blindness

  • blindness

• preformed vitamin A= in animal foods

• provitamin A= beta carotene (found in orange and green veggies)

• retinol

• acne

vitamin D

• fat soluble

• sources

  • sun

  • fortified dairy

  • fatty fish

  • fortified cereals

• major function

  • regulates calcium levels

  • immunity

  • decreases risk for many diseases

• defiency

  • rickets

  • osteomalacia

  • muscle pain/ weakness

• “sunshine vitamin”

• UV rays hit skin and cholesterol is needed to convert to vitamin D like a hormone and a vitamin

• may raise RDA

Vitamin E

• fat soluble

• sources

  • vegetable oils

  • nuts/seeds

• major function

  • antioxidants

Vitamin K

• fat soluble

• sources

  • leafy greens

  • green veggies

  • vegetable oils

• major function

  • bones

  • blood clotting

• bacteria in large intestine that can make vitamin K

• newborns are given an injection of vitamin K within 6 hours of birth

thiamin (B1)

• water soluble

• sources

  • grains

  • sunflower seeds

  • potatoes

  • pork

• major functions

  • energy metabolism

• deficiency

  • beriberi

riboflavin (B2)

• water soluble

• sources

  • grains

  • milk/ yogurt

  • liver

• main function

  • energy metabolism

• exposure to light breaks it down

grains are a good source of most of all

B vitamins

most B vitamins function in

energy metabolism

niacin (B3)

• water soluble

• sources

  • grains

  • poultry

  • meat

  • fish

• main function

  • energy metabolism

  • lowers LDL

  • raises HDL

• deficiency

  • pellagra

• used to treat high cholesterol

• can be made from tryptophan (amino acid)

pantothenic acid (B5)

• water soluble

• sources

  • widespread among food groups

• main function

  • energy metabolism

vitamin (B6)

• water soluble

• source

  • grains

  • potatoes

  • meat/fish/poultry

• main function

  • energy metabolism

  • immunity

  • synthesizes many compounds

biotin (B7)

• water soluble

• sources

  • grains

  • egg yolks

  • wide spread

• main function

  • energy metabolism

folate (B9)

• water soluble

• sources

  • grains

  • legumes

  • green veggies

• main function

  • energy metabolism

  • healthy red blood cells

  • prevention of birth defects

• deficiency

  • one type of anemia

  • neural tube defects

• greatest needs are during pregnancy= right after conception

  • also known as folic acid (grains are fortified with folic acids)

Vitamin (B12)

• water soluble

• sources

  • meat/ poultry/fish

  • dairy

• main functions

  • energy metabolism

  • healthy red blood cells (works with folate)

• deficiency

  • one type of anemia

• stored in liver

• natural vs. fortified

• older adults and vegans at risk for deficiency

Vitamin C

• water soluble

• sources

  • citrus fruit

  • peppers

  • green veggies

  • potatoes/ tomatoes

• main function

  • antioxidant

  • immunity

  • collagen

• deficiency

  • scurvy

• also known as ascorbic acid

• smokers need more

• helps absorb non heme iron

• from plant foods

• may shorten duration of colds

choline

• vitamin like

• main function

  • healthy cells

• important during pregnancy

what are antioxidants?

• substances that protect cells from damage

• they neutralize free radicals

  • helps reduce chronic diseases, aging related damage

what vitamins are antioxidants

• vitamin c

• vitamin e

• vitamin a

what are preformed vitamins

• already in their active form

• can be used by the body immediately

what are provitamins

• inactive forms that must be converted by the body

what are the 2 categories of vitamins

• fat soluble vitamins

• water soluble vitamins

fat soluble vitamins

• stored in body fat

• absorbed with dietary fat

water soluble vitamins

• not stored much in the body

• excess is excreted in urine

are vitamins organic or inorganic?

• organic compounds meaning they contain carbon

how are fat soluble vitamins absorbed

• absorbed with dietary fat

• require bile for digestion

• enter lymph system first, then bloodstream

how are water soluble vitamins absorbed

• absorbed directly into the bloodstream

• do not require fat

• travel freely in blood

bioavailability

• the degree to which a nutrient is absorbed and used by the body

factors that affect bioavailability

• food source

• preparation method

• interacts with other nutrients

alcohol calories per gram

• alcohol provides 7 calories per gram

• these are considered empty calories (no nutrients)

alcohol proof

2 x % alcohol by volume

40% alcohol is

80 proof

is alcohol a stimulant or depressant

• depressant

  • slows down the central nervous system

each drink contains

14 grams of pure alcohol

standard drink sizes

• 12 oz beer

• 5 oz wine

• 1.5 oz liquor

BAC

0.08%