Nutrition Exam 1

Nutrient

-a chemical needed by an organism to live and grow

-found naturally in foods- not made by body

what is a calorie?

the amount of heat it takes to raise the temperature of 1 gram of water by 1 degree celsius

6 classes of nutrients:

1. carbohydrates

2. fats

3. proteins

4. vitamins

5. minerals

6. water

macronutrients

energy yielding nutrients

how many cal/g of energy in carbohydrates

4 cal/g

how many cal/g of energy in fat (lipid)

9 cal/g

how many cal/g of energy in protein

4 cal/g

is alcohol a nutrient

NO, because it is not essential and interferes with growth

micronutrients

non-energy yielding

-vitamins and minerals

Function of water as a nutrient

fluid balance, temperature, chemical reactions, wastes

which is the most energy dense of the 6 nutrients?

fat (lipids)

Phytochemicals

non-nutrient compounds of vegetal origin that confer color, taste, or other characteristics. Some are bioactive food components and contribute to health

Bioactive Foods

non-essential molecules present in foods that can modulate one or more metabolic processes, promoting health

7 types of DRIs:

1. Recommended Dietary Allowances (RDA)

2. Adequate Intakes (AI)

3. Chronic Disease Risk Reduction Intakes (CDRR)

4. Tolerable Upper Intake Levels (UL)

5. Estimated Average Requirements (EAR)

6. Acceptable Macronutrient Distribution Ranges (AMDR)

7. Estimated Energy Requirement (EER)

Recommended Dietary Allowances (RDA)

98% of the population

Adequate Intakes (AI)

least evidence (good for water and fiber)

-for males 19-30 years: 38g of fiber, 3.7L of water

-for females 19-30 years: 25g of fiber, 2.7L of water

Tolerable Upper Intake Levels (UL)

how much you can eat of something until its toxic

-not a goal, but a ceiling

-UL for vitamin C for adults: 50 microliters per day

Estimated Average Requirements (EAR)

at least ½ of the population

-females need about 2000 kcal/day

-males need about 3000 kcal/day

Estimated Energy Requirement (EER)

how many calories you can eat

Acceptable Macronutrient Distribution Ranges (AMDR)

carbs: 45-65% total energy

protein: 10-35% total energy

fat: 20-35% total energy

If a male should consume 3000kcal a day, how many carbs did he eat this day in grams?

50% of his diet was carbs

energy from carbs: 4 cal/day

(3000/4) x 0.5 = 375g

0.5 comes from 50%

3 options when body needs energy:

1. transfer food energy into ATP: fed state

2. transfer stored energy into ATP: fasting state

3. suffer from energy deficit

Energy balance

energy intake vs output

positive energy balance leads to:

weight gain

basal metabolism

energy used to maintain essential functions

BMR= basal metabolic rate

-where most energy expenditure occurs

thermic effect of food

energy used to breakdown nutrients and store energy from food (minimal)

-where least energy expenditure occurs

who has a 10x risk of dying compared to peers?

-young adults ages 15-24 with anorexia

-males in comparison to females

Orthorexia

obsession with healthy eating and/or lifestyle- not a medical diagnosis

what is %DV used for

comparing brands or products

-reflects highest level of nutrient needed among all populations age 4 and older

-generally based on 2000 kcal diet

Daily value of fiber in g for 14%, 4 servings per container

(100/14) x 4 = 28

general guides for DV

-5% DV or less of a nutrient per serving is considered low

-20% DV or more of a nutrient per serving is considered high

How often are the dietary guidelines for Americans updated?

every 5 years

What is the DGA recommendation for sodium?

less than 2300 mg/day

What is the DGA recommendation for added sugars?

less than 10% of calories

What is the DGA recommendation for saturated fat?

less than 10% of calories

What is the DGA recommendation for alcoholic beverages?

males: 2 drinks or less per day

females: 1 drink or less per day

ex: if a person eats 2000 calories a day, how many calories should come from added sugars? How many grams of sugar contain 200 calories?

1. 200 calories

2. 50g (carbs provide 4cal/g so 200/4)

Which nutrients are underconsumed?

calcium, potassium, fiber, and vitamin D

How much of your grains should be whole?

1/2

enrichment vs. fortification of grains

enrichment: adding nutrients back to a food to return content to original levels after processing

fortification: addition of nutrients above what natural food normally contains

Healthy Eating Index (HEI)

range from 0-100

-tool to evaluate diet quality

how many cups of fruit are suggested per day?

2 cups

how many cups of veggies are suggested per day?

3

how many ounces of grains are suggested per day?

8

how many ounces of protein are suggested per day?

6.5

how many cups of dairy are suggested per day?

3

Legumes

-a plant in the family Fabaceae or the fruit or seed of such a plant

-have nitrogen fixing bacteria in root nodules

Absorption:

when nutrients move through wall of GI tract to enter blood or lymphatic vessels

GI Tract consists of:

mouth, esophagus, stomach, small intestine, large intestine

2 types of digestion:

mastication and enzymes

which enzyme is found in the mouth

salivary amylase

food passes through ____ to enter stomach.

lower esophageal sphincter

digestion in the stomach =

churning (physical) + gastric juices (chemical)

-secretes intrinsic factor

-protein and lipids begin chemical digestion here

stomach secretions:

-mucus

-gastric acid

-gastric lipase

-intrinsic factor

Digestive enzymes in gastric juice:

gastric lipase and pepsin

chyme

food bolus + gastric juice

How often does the stomach empty out

every 2-4 hours but depends on quantity of food and quality/nutrient content

Small Intestine outer layer:

holds blood and lymph vessels that pick up newly absorbed nutrients

submucosa layers:

innervated by nerves and blood vessels

mucosa layer

skin cells

-make substances and enzymes needed for digestion

-allow nutrients to pass into blood and lymph vessels

Small intestine

16-20 feet long, divided into 3 sections

-major site of digestion and absorption

-carbs, proteins, and lipids digested to completion

secretin:

in the small intestine

-signals secretions from stomach and pancreas

SI

release of mucus, pancreatic enzymes and bicarbonate ions

CCK:

signals gallbladder to release bile

components made by small intestinal cells:

-mucus by goblet cells

-digestive enzymes for carbs, fats, and proteins

-hormones that regulate digestion processes

components made by accessory organs

-bicarbonate ions to neutralize acid

-digestive enzymes for carbs, fats, and proteins

-bile to help digest fats

Intestinal enzymes:

peptidases, sucrase, lactase, maltase

pancreatic juice:

pancreatic amylase, pancreatic lipase, pancreatic proteases

gastric juice

protease, gastric lipase, and hydrochloric acid

Liver

-body’s most metabolic organ

-makes bile

-sends bile to gallbladder for storage

large intestine (colon):

reabsorbs water and minerals

bile

emulsifies fat