Nutrition - Midterm

macronutrients… aka “energy yielding”

• carbs

• protein

• fats

micronutrients

• vitamins

• minerals

non-energy-yielding nutrients

• vitamins

• minerals

• water

what happens when the body uses energy yielding nutrients?

The bonds between the atoms break and release energy.

• we need to blow up foods to utilize them

• breaking bonds releases energy

calorie

amount of energy needed to raise the temperature of 1 gram of water by 1 degree celsius

carbs calories per gram

4 kcal/g

fat calories per gram

9 kcal/g

protein calories per gram

4 kcal/g

alcohol calories per gram

7 kcal/g

Which of the following facilitates the release of energy from

carbohydrate, fat, and protein without actually providing energy?

vitamins - lots of B vitamins are involved in the release of energy from macronutrients

Dietary Reference Intakes (DRI)

set of nutrient intake values for healthy people in the Unites States and Canada

what does DRI include

• estimated average requirements

• recommended dietary allowance

• adequate intakes

• tolerable upper intake levels

RDA nutrient compared to EAR

RDA is set well above the EAR

EAR

estimated average requirement

• daily necessity to live

RDA

Recommended Dietary Allowance

• is there a limit?

AI

adequate intake

• we gather information and conclude how much we should be absorbing

UL

tolerable upper intake levels

• limit for intake

magnesium RDA

through food there is no limit, through supplements it is 350 mg

The estimated average requirement (EAR) meets the needs of ___% of the population

50

Tolerable UL protect against _______

toxicity

The ____ meets the needs of most healthy people in the population

RDA

The adequate intake (AI) is when there isn’t enough evidence

to establish the ___. It is used instead of the ___.

EAR, RDA

The RDA will always be set above/below the EAR.

above

EER

estimated energy requirement

PAL

physical activity level

carbohydrate macronutrient distribution range

45-65%

protein macronutrient distribution range

15-25%

fat macronutrient distribution range

20-35%

What is the maximum number of grams of fat recommended on a

1800 kcal diet based on the AMDR?

70

top 3 leading causes of death in the united states

1. heart disease

2. cancer

3. unintentional injuries

4. stroke

causes of death that food has a large role in

• heart disease

• cancer

• stroke

• diabetes

• chronic liver disease

criteria of ultra processed foods

• depends hoe extensively the food was processed

• nutritional value diminishes when changes are extensive

• no longer represent a whole food

what is true of digestion?

it breaks food down into nutrients

start of digestion

mouth

• bolus of food passes through the pharynx and then upper esophageal sphincter

digestion: esophagus and stomach phase

bolus moves into the stomach and chyme forms

digestion in the small intestine

• pancreatic juices from pancreas to digest and neutralize

• bile from gallbladder to emulsify fats

• intestinal enzymes break apart macros

digestion in large intestine (colon)

• resorption of water

• fiber fermentation

• excretion of waste

two types of digestion

• mechanical

• chemical

bacteria roles

ferments some fibers

fiber role

retains water

undigested foods

fibers, connective tissue, and cellular debris

the colon role

absorbs water and recycles dissolved salts

fat and protein take longer to digest than carbs (t/f)

true

when fat and protein are present, intestinal motility slows to allow time for digestion (t/f)

true

when fat is present in the intestine, the pancreas contract and releases bile into the intestine (t/f)

false - gallbladder and liver produce bile

the upper esophageal sphincter closes after the bolus passes through and prevents reflex from the stomach (t/f)

false - lower, not upper

digestive enzymes are comprised of carbohydrases, lipases, and proteases

true

nutrient absorption

mostly occurs in small intestine

how vitamins get absorbed

they require a carrier

active transport

requires energy to move products across the membrane

• glucose and amino acids

what happens to nutrients in the bloodstream

• water-soluble nutrients and smaller products of fat digestion

• go to liver first

what happens to nutrients in the lymphatic system

• for larger fats and fat-soluble vitamins

• chylomicrons carry fats

• bypass liver at first

how the lymph and blood stream differ

• blood stream - nutrients are collected from the intestine and go to the liver via hepatic portal vein

• lymphatic system - nutrients absorbed into lymph do not go to liver first. They instead go to the heart which pumps it to all the body’s cells. Cells remove the needed nutrients and then the liver deals with the remains

prebiotics

• feel good bacteria

• fiber that help fuel the good bacteria

• reach gut microbiome

probiotics

• fight bad bacteria

• in foods that contain live bacteria

• beneficial bacteria

microbes in the GI tract…

are directly influenced by diet that contains prebiotics and probiotics

how the digestive system should be

• sensitive and responsive to environment

  • immunity against intestinal diseases

  • defense against foreign invaders

• create and maintain healthy system

  • adequate sleep, exercise, stress management, diet balance, moderation, adequacy, and variety

role of bile

emulsify fats

monosaccharides

• glucose

• fructose

• galactose

disaccharides

• sucrose (glucose and fructose)

• lactose (galactose + glucose)

• maltose (glucose + glucose)

polysaccharides

• starches

• fibers

• glycogen

The brain uses ____ as its primary energy source

glucose

Muscles store simple sugars in the form of .

glycogen

excess sugars are stores as

fat

amylopectin

hundreds of glucose molecules in branched chains

• type of starch

amylose

hundreds of glucose molecules in unbranched chains

• type of starch

starchy foods

• bread

• cereals

• pasta

• rice

• potatoes

• beans

• chestnuts

Glycogen and starch are examples of ________

polysaccharides

Glycogen is the storage form of energy in ______.

animals

Starch is the storage form of energy in _____

plants

carbohydrate digestion organs

• mouth

• stomach

• small intestine

• large intestine

mouth role in starch digestion

• salivary glands secrete saliva

• amylase begins digestion of starch into small polysaccharides and maltose

mouth role in fiber digestion

mechanical action crushes and tears fiber and food and mixes it with saliva to moisten it for swallowing

stomach role in starch digestion

acid inactivates amylase which halts digestion

stomach role in fiber digestion

• not digested

• delays gastric emptying

small intestine and pancreas role in starch digestion

• pancreas produces an amylase that is released into the small intestine to break it down to polysaccharides and maltose

• disacchridase enzymes on small intestine surface hydrolyze them into monosaccharides

which carbs require active transport

• glucose

• galactose

which carbs require facilitated diffusion

fructose

liver role in carb absorption

converts fructose and galactose to glucose

what takes place in the large intestine during carb digestion?

fiber attracting water

health effects of sugar

• obesity

• chronic diseases like diabetes and CVD

• nutrient deficiencies

• dental caries

The Dietary Guidelines for Americans urge consumers to

limit intake of added sugar to

10% of total kcal/day

type of carbs that cause blood glucose concentrations to rise faster

simple and added sugars

AMDR for carbs

45-65% of energy requirement

RDA for carbs

130 g a day

DV for fiber

11.5g/1000 kcal

AI for fiber

14g/1000 kcal

health benefits of fiber

• reduced coronary heart disease risk

• reduced type 2 diabetes risk

• reduced colorectal cancer risk

• reduced body weight, cholesterol, and blood pressure

health benefits of fiber

• delay emptying of stomach - slowing entry of glucose into bloodstream

• typically do not cause blood glucose to rise

• cholesterol-lowering effect reduces risk of heart disease

negatives of overconsumption of fiber

• insufficient energy or nutrients

• abdominal discomfort, gas, diarrhea

• GI obstruction if not consuming enough fluids

tips to eat more fiber

• whole grains

• nuts and seeds

• beans and legumes

• high fiber snacks

dominant lipids in our diet

triglycerides

saturated fatty acids

no double bonds

unsaturated fatty acids

have a double bond

monounsaturated

one double bond

polyunsaturated

multiple double bonds

structure of triglycerides

• 3 fatty acids

• glycerol

linoleic

• omega-6 fatty acid

• 2 double bonds

• sunflower, safflower, corn, and soybean oils

linolenic

• omega-3 fatty acid

• 3 double bonds

• soybean and canola oils, flaxseed, walnuts

ends of the fatty acid chains

• methyl or omega end on the left

• acid or alpha end on the right