NUSC 1165 - unit 1 review

What is nutrition?

science which studies all interactions that occur between living organisms and food

what are nutrients?

chemical substances in what we consume that provide energy + structure that help regulate body processes

how are nutrition and disease related?

- Poor nutrition leads or underlies disease and death- Good nutrients prevent disease and death

what are some ways we see the science of nutrition in practice?

- Public health- Behavioral science + nutrition- Obesity, social/cultural practices

what are the 6 factors that affect food choice?

1. availability
2. health concerns
3. culture
4. psychological & emotional
5. social acceptability
6. personal preference

what is similar between nutrition and nutrients?

they both refer to nourishment

how does nutrition differ from nutrients?

nutrients are the ones that provide the nourishment that nutrition talks about

how healthy is american diet?

* American adults eat more calories than they did 50 years ago
* 2/3 of Americans are overweight
* Americans don't eat enough of the foods needed to make up a healthy diet
* current dietary patterns and lack of physical activity increase risk of chronic diseases

what are the 3 aspects/concerns to the american diet healthfulness?

1. increase in food consumption and calories
2. underconsumption
3. overconsumption

how does the increase in food consumption and calories relate to the american diet?

means today most americans consume larger portion sizes, fast food, salty snacks, and sweetened beverages- also increase in dining out

how does underconsumption relate to the american diet?

most don't consume enough:

\- whole grains, legumes, veggies, fruits, seafood, and low-fat dairy

\--

these foods all contain nutrients that promote health

how does overconsumption relate to the american diet?

they over eat : meats, fat, and sugars

\- this can be potential link to chronic disease risk

what are non-essential nutrients?

* substances in food that not essential for life BUT beneficial to health
* they are produced by human body
* ex: Lecithin: egg yolks --> needed for nerve function

what are essential nutrients?

* obtained solely from diet
* not produced by body or in large amounts to meet needs --ex: Vitamin C

what are the 5 categories of nutrients? (how are nutrients classified)

1. energy yielding
2. macronutrients
3. micronutrients
4. inorganic
5. organic

What are the energy yielding nutrients?

carbs, proteins (4 kcal/g), lipids/fats (9kcal/g)

What are macronutrients?

Carbohydrates

Lipids

Proteins

Water

What are micronutrients used for?

vitamins, minerals, supplements.

(used by body, not for energy production)

What are the micronutrients (trace elements)?

vitamins and minerals:

* B Vitamins
* Vitamin C
* Vitamin A
* Vitamin D
* Vitamin E
* Vitamin K
* Calcium
* Iron

What are inorganic nutrients?

minerals and water

what are organic nutrients?

carbohydrates, lipids, proteins, vitamins

what do inorganic molecules NOT contain in their chem structure but organic molecules do?

carbon

When considering the nutrient density of a food or beverage, what two factors should an individual compare?

1. How much energy it gives you (energy contribution)
2. Comparing nutrients in one and the other

What is nutrient density?

a measure of the nutrients a food provides compared to its energy content

what is a common known fact that relates to nutrient density?

Fresh fruits and vegetables are lower in calories AND have high nutrient density.

what are the 3 components to a healthy diet?

variety, balance, moderation

what is a variety in relation to diet?

Involves selecting nutrient dense foods from each food group and within each group.

what is a balance (diet)?

One food lacking in a nutrient, balance with another food that does

what is moderation? (diet)

* knowing all types of food are okay
* Not consuming too much energy, fat, sugar, or alcohol
* exercising or increasing your energy intake can help

what is a source that can help us choose a healthy diet? (with variety & balance)

MyPlate

what is the scientific method?

the general approach that helps us explain observations of the world

What are the steps of the scientific method?

observation, hypothesis, experiment, conclusion (theory)

\- if first hypothesis doesn't work you can restart with another

What is an observational study?

An observational study measures the value of the response variable without attempting to influence the value of either the response or explanatory variables.
- there's correlation of 2 or more factors- can include case control studies (compares indiv.)

what is an intervention study?

manipulating something and wanting to see its effect

\- there can be control vs experimental groups

What is epidemiology?

looking/observing at what is happening around us and trying to find patterns

what are lab studies?

* Nutrient function
* Evaluates relationships
* Cell to organism
* Biochemistry different in nutrition (does not go fully in depth

why were nutrition labels updated?

to present realistic calories and serving sizes so people know what exactly they are putting in their bodies

what changes/additions are seen in new food label?

* Calories from fat removed + vitamins A and C
* (Type of fat)
* Serving size: now has actual vs ideal consumption
* Packages with 1-2 servings
* Vitamin D, potassium, calcium added as well as their %DV
* New footnote more clearly explains meaning of % DV
* calories much larger
* added sugars now shown

what 2 things listed in %DV are to be limited?

added sugars and saturated fats

when is a nutrient considered high on a food product?

it must say 20% or above on %DV

when is a nutrient considered to have low amount on food product?

anything below 5% DV

what are 3 typed of nutrition claims?

1. health
2. nutrient
3. structure/function

what are nutrient content claims?

describe level or amount of a nutrient in food product (approved by FDA)

\--Frequent words (by FDA) "low", "high", "free", "reduced", "lean", "high potency", "antioxidant", "light"

what are structure/function claims?

describe how nutrient affects human body structure or function, such as "iron builds strong blood"

* do NOT focus on disease reduction (health claims do that) they are NOT FDA approved

What are health claims?

describe a relationship between a food or dietary compound and a disease or health-related condition

\--\*cheerios best example: they say they are good for your heart (marketing)

what are dietary supplemental claims/why are they used?

Any product intended for ingestion as a supplement to the diet:

* not strictly regulated as drugs
* Manufacturers responsible for product safety

What does the Dietary Supplement Health and Education Act do?

requires all dietary supplements carry a standard label under DSHEA specifications

what does it mean when a label claims it has "good source"?

that food contains 10-19% of the DV for a particular nutrient per serving

what does it mean when label claims "reduced"?

Nutritionally altered product contains 25% or less of a nutrient or of energy than the regular or reference product

how does labeling of food served at restaurants work?

They don't have to adhere to labeling...unless they have a large restaurant chain of more than 20 restaurants

* They must have nutrition info available upon requests in restaurant that has claim made about a menu item's nutritional content
* 20 or more vending machines fall under this rule too

who was the healthy people initiative developed by?

US Department of Health and Human Services (Surgeon General Julius Richmond)

what are goals of healthy people initiative/what do they help with?

- Increase quality and the length of healthy life- Eliminate health disparities

how often does the Healthy People renew?

every 10 years

Goals of Healthy People 2020

1. Attain high-quality, longer lives free of preventable disease, disability, injury, and premature death.
2. Achieve health equity, eliminate disparities, and improve the health of all groups.
3. Create social and physical environments that promote good health for all.
4. Promote quality of life, healthy development, and healthy behaviors across all life stages.

what are the organ systems responsible for obtaining and using nutrients in food?

* digestive system
* nervous system
* endocrine system

what does digestive system do?

* ingestion and digestion of food
* facilitates movement of nutrients into body
* responsible for eliminating unabsorbed waste

what does nervous system do?

"like our simulating tool"

* sends nerve signals to help control the passage of food throughout the digestive tract (gi tract)

what does endocrine system do?

"all about hormones"- produces hormones to regulate food intake and the function of digestive organs

what are the organ system responsible for the elimination of metabolic waste products?

* urinary system
* respiratory system


* integumentary system

what does urinary system do?

elimination of fluids

what is purpose of respiratory system?

removes carbon dioxide from the body, delivers oxygen to blood

whats the purpose of the integumentary system?

removal of water and minerals through the skin

what is the order of the organization of life?

Atoms → Molecules → Cell → Tissue → Organ → Organ System → Organism

atoms...

can't be broken down (carbon, hydrogen, oxygen, nitrogen)

molecules

formed from atoms held together by chemical bonds

cells

formed from molecules

tissue

groups of similar cells from tissues

organs

perform specialized functions

organ system

group of organs that work together(ex: digestive system)

organism

functioning of organ systems

what are the 2 functions of digestion?

1. Breaking food into components small enough so it can be absorbed into body
2. Energy yielding nutrients: carbohydrates, protein and fats

what has to happen before digestion?

absorption

what is absorption?

process of taking substances directly into the body

what is the main site of digestion & absorption?

Organs of the gastrointestinal tract & Accessory Organs

what are organs of gastrointestinal tract?

mouth,

pharynx

esophagus

stomach

small intestine

large intestine

anus

mouth

chews food and mixes it with saliva

Moistens the food, cleanses mouth, protects teeth, and lubricates the upper digestive tract.

pharynx

swallows chews food mixed with saliva

esophagus

moves food to stomach

stomach

churns and mixes food; secretes acid and a protein-digesting enzyme

small intestine

completes digestion; absorbs nutrients into blood or lymph

large intestine

absorbs water and some vitamins and minerals; home to intestinal bacteria; passes waste material

where can colon and rectum be found?

gastrointestinal tract

anus

opens to allow waste to leave the body

what do organs of the gastrointestinal tract come DIRECTLY in contact with?

digested food

What are the accesory organs?

salivary glands, liver, gallbladder, pancreas

salivary glands

produce saliva which contains a starch digesting enzyme

liver

makes bile, which aids in digestion + absorption of fat

pancreas

Releases bicarbonate to neutralize intestinal contents; produces enzymes that digest carbohydrate, protein, and fat

gallbladder

stores bile and releases it into the small intestine when needed

what is purpose of accessory glands?

* They produce substances that assist with digestion
* They have no direct contact with the digested food

What enzyme is present in saliva?

salivary amylase

the stomach is..

constructed of three layers of strong muscle tissue Temporary storage site for food:

Production of hydrochloric acid

Chyme

Stomach Wall

structure of gut wall..

* Lumen→
* Mucosa- There is some digestive and absorption that actually occur
* 5 day lifespan in the cells in mucosa
* Connective tissue→ surrounds mucosa: Contains nerves and blood vessels; keeps structure alive
* Gives support to liver nutrients and sends nerve signals IMPORTANT for contraction


* Smooth muscle: Helps with mixing of foods with all these digestive products → Surrounds connective tissue to contract and push food forward
* Also made up of some connective tissue + provides another layer of support

where are the specialized cells of the stomach found?

in gastric glands and produce gastric juice

what are the specialized cells of the stomach?

1. parietal cells 2. chief cells 3. mucous cells

What are parietal cells?

hydrochloric acid intrinsic factor (needed for vitamin B12 absorption)

what are chief cells?

they Secrete pepsinogen (inactive enzyme),

* includes gastric lipase: Acid in stomach activates pepsinogen to pepsin

what are mucous cells

* they secrete mucus-
* Protects lining of stomach from acid and pepsin

the small intestine is the main site of what?

digestion and absorption

what 4 things are found inside small intestine?

* villi
* microvilli
* lacteals
* capillaries