Nutrition Exam 1

What is nutrition?

The science of food; the nutrients and the substances therein; their action, interaction, and balance in relation to health and disease; and the process by which the organism ingests, digests, absorbs, transports, utilizes, and excretes food substance

Nutrients

Substances essential for health that the body cannot make or makes in quantities to small to support life

Characteristics of essential nutrient

• has specific biological function

• absence from the diet leads to decline in biological function

• adding missing substance back to the diet before permanent damage occurs restores normal biological function

Functional categories of nutrients

• primarily provide energy

• important for growth and development

• keep body functions running smoothly

Some overlap exists among the groupings

Macronutrients are needed in large amounts

carbs, lipids, proteins, water

micronutrients are in small amounts

vitamins, minerals

Carbs

• composed of C, H, O

• primarily obtained from fruits, veggies, grains, and beans

• 4 kcal/g

Protein

• composed of C, H, O, N

• main structural component in the body

• 4 kcal/g

• formed from bonding of amino acids

Lipids

• composed of C, H, O

• insoluble in water

• 9 kcal/g

Organic molecules that yield energy

Carbs, proteins, lipids

Vitamins

13 vitamins

• fat and water soluble

• unique functions

facilitate energy release but do not provide energy

almost every bodily action requires assistance from vitamins

organic molecules

vulnerable to destruction by heat, light, and chemicals

Minerals

16 essential minerals

• major minerals needed in gram amounts daily

• trace minerals needed in <100 mg daily

Inorganic substances

not destroyed by cooking

yield no energy

required for normal body function

Ex: iron, magnesium, potassium, sodium, copper

Water

needed in the largest quantity of all nutrients

vital functions: solvent, lubricant, transports nutrients, and regulate body temp

sources: food and drink, byproduct of metabolism

nutrients that provide energy

most carbs, proteins, most lipids

nutrients that promote growth and development

proteins, lipids, some vitamins, some minerals, and water

nutrients that regulate body processes

proteins, some lipids, some vitamins, some minerals, and water

phytochemical

physiologically active compounds found in plants that may provide health benefits

zoochemicals

physiologically active compounds found in foods of animal origin that may provide health benefits

phytochemical and zoochemicals are ________ essential nutrients

not considered

energy sources

carbs, proteins, fats, and alcohol

with energy, we can

build new compounds, move muscles, transmit nerve impulses, and balance ions within cells

What is a calorie

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

kilocalorie

amount of heat energy needed to raise the temperature of 1000 gram of water 1 degree celsius

more appropriate unit for food

physiological fuel values

carbs =4 kcal per gram

fat =9 kcal per gram

protein =4 kcal per gram

alch =7 kcal per gram

what influences our food choices?

daily food intake is a mix of our need to satisfy hunger and social and psychological needs

hunger: physical need for food

appetite: psychological desire to eat

appetite and food choice depend on many factors

nutrition timeline

Early 1900s- discovering nutrients

1950s -discovery of dna

2000s- nutrigenomics

2012- human microbiome sequenced

defining research

• systematic process of collecting, analyzing, and interpreting information/data to extend knowledge

• systematic process typically refers to scientific method

• researches use scientific methods to guide research studies

quality research is the ________ for nutrition practices

foundation

Lab animals

only used when cant test on humans

Limitation of using lab animals

• physiological differences

• mechanisms of cancer is diff

• dietary needs

• animals can control everything

Human studies

must be approved by research review board and obtain informed consent

observational: cohort studies, case control, cross sectional

experimental: randomized controll trials, single arm trial

cohort study

• observe a group of individuals over a period of time

• limitation: cant claim cause and effect

case control study

individuals who have the condition are compared to those that do not

strongest studies compare groups that are similar in multiple factors

Limitation: cannot claim cause and effect

Correlation ____ causation

is not

randomized control trials

• gives more definitive testing of a hypothesis

• experimental group follows a protocol

• control group usually receive a placebo

• in a single blind study only the participant does not know who is receiving the placebo or the treatment

• To help reduce bias

  • neither study participants nor researchers know who is in which group (double blind)

  • expected effects of protocol are not disclosed reducing the chance of placebo effect

peer review

other scientists review

ensures most unbiased, objective findings are published

follow up studies

one experiment is not enough, results must be confirmed by more experiments by other scientists

systematic review and meta analysis

critical evaluation and synthesis of research studies focusing on a specific topic or research questions

• used to help determine which clinical methods are likely to help patients

evaluating nutrion claims, products, and advice

1. apply basic principles of nutrition

2. be wary when have unusual or extreme statements

3. examine scientific credentials

4. look at the research behind claims

5. look at press headlines and other hype

nutritionist

literally anyone

registered dietitian

• national certification

• licensure in some states

scope of practice

legal scope of work based on academic training, knowledge, and experience

protect consumers and practitioners

specific recommendations by qualified practitioners

recognize limitations of knowledge, training, and expertise

dietary reference intakes (DRI)

standard defined for almost 40 nutrients

• energy

• nutrients

• other dietary components

Who are DRIs for?

differe by life stage

• age group

• gender (After age 9)

• pregnancy

• lactation

what are DRIs used for?

scientific basis and tool to determine dietary guidelines

Types of DRIs

Estimated average requirements

adequate intakes

estimated energy requirements

recommended dietary allowances

tolerable upper intake levels

adequate macronutrient distribution ranges

DRIs are ________ as new research is available and synthesized

updated

Estimated average requirements

ears meet the needs of 50% of those in a life stage

set based on optimal intake for functional markers of the nutrient

EAR are used to evaluate

adequacy of diets of population R

Recommended Dietary Allowances

daily nutrient intake amounts suf to meet needs of nearly all individuals in a life stage

RDA=

EAR*1.2

RDA is an amount to prevent

deficiency and chronic disease

Adequate intake used when

not enough info on EAR

Adequate intake is based on

observed or experimental determined estimates of the average intake that appears to maintain a defined nutritional state

Every nutrient has EAR or AI…not

both

Tolerable upper intake levels

maximum daily intake without adverse health effects

UL are based on nutrient intake from

all sources

UL are not a

goal but a ceiling

Estimated energy requirements

average daily energy need for each life stage group

Acceptable macronutrient distribution ranges

not a DRI but guidance for carbs, proteins, fat and essential fatty acids

Appropriate Uses of the DRIs

• intended for diet planning

  • should aim to meet any RDAs or AIs set

  • Goals intended to be met through foods

• Recommendations-does not mean optimal

  • Do not exceed the upper level for a nutrient

• Can be applied to healthy people

  • May not be appropriate for the undernourished or those disease or other health conditions

higher nutrient density=

more nutritious choice

3 examples of nutrient dense food

protein bar, fruits, veggies

3 examples of low nutrient dense food

candy, chips, chocolate

achieve the goal of healthy eating: meal planning

goal: eating pattern that provides

• needed nutrients without excess energy (calories)

6 diet planning principles

1. adequacy

2. balance

3. energy control

4. nutrient density

5. moderation

6. variety

dietary guidelines for Americans

• USDA and DHHS release the dietary guidelines every 5 years

• foundations of US government nutrient policy and education

• designed to meet nutrient needs and reduce the risk of chronic disease

dietary guidelines for americans

1. follow a healthy dietary pattern at every life stage

2. customize and enjoy nutrient-dense food and beverage choices to reflect personal preferences, cultural traditions, and budgetary

3. Focus on meeting food group needs with nutrient-dense foods and beverages, and stay within calorie limits

4. Limit foods and beverages higher in added sugar, saturated fat, and sodium, and limit alcoholic beverages

Key themes of healthy dietary patterns in the dietary guidelines

• a variety of vegetables from all subgroups-dark green, red and orange, bean and peas, starchy vegetables

• fruits, especially whole fruits

• grains, at least half of which are whole grains

• fat-free or low-fat dairy, including milk, yogurt, cheese, and/or fortified soy beverages

• a variety of protein foods, including seafood, lean meat and poultry, eggs, legumes, and nuts, seeds, and soy products

• oil

USDA Food patterns are based…

on the dietary guidelines for americans.

healthy eating patterns are…

flexible to accommodate an individual’s personal, cultural, traditional preferences and financial resources

Dietary guidance for individuals

Consider:

• traditions

• access to food

• food preparation skills

• possible health needs

• food preferences

MyPlate

• designed by the USDA

• MyPlate depicts the key elements of a healthy diet

• Emphasizing the fruit, vegetable, grain, protein, and dairy food groups

• The goal is to remind consumers to think about building a health plate at mealtimes

Who has oversight of food labels?

US Food and Drug administration has oversight

Nutrient Facts Panel must haves

• total calories

• total fat, saturated fat, and trans fat

• cholesterol

• sodium

• total carbs, fiber, total sugars, added sugar

• protein

• vitamin D

• potassium

• calcium

• iron

What is required on labels?

• product name

• name and address of manufacturer

• amount of product in the package

• ingredient list in descending order by weight

• ingredients that are common allergens

• nutrition facts panel

Whats on the nutrition facts panels

represents information for a single serving of food

• serving sizes are specified by FDA

• based on typical serving size eaten by Americans

• consistent across similar products

• 1 serving does not necessarily mean 1 servings in the USDA

% daily value

• how much nutrient in a single servings of an individual packaged food or dietary supplement contributes to a 2000 calorie diet not your individual dietary needs

Daily values

• generic standards developed by the US food and drug administration

2 sets of main dietary standards

RDI and DRV

Reference daily intakes

standards tend to be set at the highest RDA value for any life-stage group

Daily Reference Values

For energy-producing nutrients, cholesterol, sodium

How to use DV?

helps put it into context to know high/low

Types of food label claims

Nutrient Content Claims: describes the amount of a nutrient in a food and closely regulated by FDA

Health Claims

A relationship between a disease and a nutrient, food or food constituent and closely regulated by FDA

Structure/function claims

not FDA approved

FDA qualified health claims

• need research requirements and must have disclaimer

Structure/functional claim

certain nutrient has function in body

What about “natural”?

controversial label as nothing is truly natural as it has been processed

USDA definition of natural

no artificial ingredients, minimally processed

Factors affecting nutrient composition

• Farming conditions

• Maturity and ripeness of plants

• food processing

• shipping conditions

• storage time

• cooking processes

4 types of tissues

Epithelial, connective, muscle, nervous

tissues combine to form

organs

several organs form

organ system

Major and accessory organs of GI tract

Mouth and salivary glands —> esophagus —> stomach —> small intestine —> large intestine —> rectum —> anus

Lumen

inner space

sphincters

ringlike muscles that work like valves to control flow of contents

prevent contents from moving through the GI tract too quickly

Sphincter order

lower esophageal—> pyloric —> heptapancreativ—> ileocecal —> anal

where does digestion begin?

mouth

• mixed with saliva

food becomes bolus

Saliva is made of what three things?

Lysozyme, mucus, amylase