Nutrition Exam 1

Variety, Balence, and moderation in food choices.

A healthy diet includes

Calories from foods that offer little to no nutritional value, often found in sugary or processed foods.

Empty Calories

Published every 5 years since 1980 by HHS/USDA

Dietary Guidlines

fruit/vegies/grains, fat free or low fat dairy, protein sources, oils, exercise.

5 overarching Concepts in dietary guidlines by HHS/USDA

solid fats and added sugars/salt

Healthy Pattersn limit (SoFAS)

Foods with nutrients added to them.

Fortified Foods

Nutrients are added back that were removed during processing (Thiamin, Riboflavin, Niacin, Folate, Iron)

Enriched Foods

Increses quality of life for all

eliiminate health disparities

make social and physical environments

Healthy people 2020 (objectives)

Recommended Dietary Allowances for specific nutrients (for healthy people and catagorized by age group)

Dietary Reference Intakes (DRI)

General recommendationns for how many calories one should eat a day based on age, gender, weight, height, and activity level.

Estimated Energy Requirements (EER)

Carbs: 45%-65%

Fat: 20%-35%

Protein: 10%-35%

Acceptable Macronutrietn Distribution Range (AMDR)

USDA’s MyPlate is daily plan for food intake

Replaced MyPyramid

MyPlate

• Vegetables

• Fruits

• Grains

• Dairy

• Protein

5 food groups of MyPlate

• lets you enter personal info to get a personal meal plan

  • Number of servings from each food group

SuperTracker

• Vegetables → 3 cups

• Fruits → 2 cups

• Grains → 6 oz

• Dairy → 3 cups

• Protein → 6 oz (RDA 0.8g per Kg)

How much of each food group to eat

• Food and Drug Administration FDA (do the Packaged foods)

• Food Safety and Inspection Service of the USDA (perishables)(meat, poultry, and eggs)

Regulations for food contents regulated by 2 federal agencies

• 5% or less = low 

• 20% or more = high

HIgh or low percentages for food labelling

Describes a relationship between a food and a reduced risk of a disease or a health-related condition (HAS TO ADDRESS OR LINK TO A DISEASE)

Health Claims

Describes level of nutrient in a foods (such as 50% less sugar or fat free)

Nutrient Content Claim

Describes the role of a nutrient or ingredient on the structure or function in human body (helps build strong bones) (does not have a disease addressed) (packed with vitamin C)

Structure/Function Claim

50%

EAR- estimated average Requirements (good for ___ of people)

98%

RDA - recommended Dietary average (good for ___ of people)

External

is the GI tract internal or external environment

Mouth → esophagus → stomach → small intestine (3 segments) → large intestine → anus/rectum

The tract itslef (6 segments)

Duodenum(short), jejuneum(long), ilieum(short)

Segments of small intestine

intrinsic factor and HCl and pepsin, by parietal cells

What does the stomach produce and what produces it

vitamin b12

what does intrinsic factor bind to

Bile (12 oz a day)

what does the liver produce

digests and absorbs fats/lipids (has hydrophobic and hydrophillic ends)

what does bile do

97% water, 3% bile salts

What is bile made of

cholesterol

what are bile salts

4 ringed structure with a steroid nucleus

structure of cholesteraol and what does it have

Fat

what macronutrient is cholesterol

Stores bile

What does the gallbladder do

It emulsifies fat droplets from food letting them move through your body

What does cholesterol (bile) do (and what does it do this to)

mixing of layers

What is emulsification

insulin and glucagon

What does the pancreas secrete

Insulin (most anabolic hormone in body.

Glucagon is catabolic

secreted into bloodstream

What are the endocrine functions of the pancrease

secreted out of bloodstream

pancreatic juice goes into first portion of duodenum back up the route bile took to get there

Exocrine functions of pancrease

This contains Amylase, Lipase, and Protease (one more thing there is bicarbonate ion (neutralizes stomach acid)

What does the pancreatic juice contain

• Breakdown of food to smaller components

• Done at primary site of small intestine up until jejunum

What is digestion and where does it happen

The period of time it takes food to travel length of the digestive tract (mouth to anus)

Transit time

Fiber (30g) and exercise decreases Transit time (Its good to have fast transit time since it reduces risk of colon cancer)

How to decrease Transit Time

Involves chewing, mixing, and peristalsis (swallowing)

Mechanical Digestion

Peristalsis: wavelike muscular movements (move food along tract)

What is peristalsis

bowel movement

Evacuation

Secretions and enzymes

Chemical processes

Circular muscles that separate organs of GI tract (stops back tracking)

Sphincters (what are they?)

• Lower esophageal sphincter

  • Separates esophagus and stomach

• Pyloric sphincter

  • Separates stomach and duodenum

• Ilececal valve

  • Between Ilium and colon (at cecum)

What are the 3 main sphincters

Once food mixes with stomach acid it becomes Chyme

What is Chyme

We can only absorb monosaccharides (not di or tri)

What are carbs broken down to to be absorbed

What are proteins broken down to to be absorbed

Monopeptides (single amino acids), Dipeptides, Tripeptides, are all absorbable (Oligopeptides (4) are unabsorbable)

We can absorb glycerol (3-carbon chain) or fatty acids (cannot absorb diglycerides or triglycerides)

What are fats/lipids broken down to to be absorbed

Enterocytes (intestine cells) have enzymes in their cells that cleave peptides into individual amino acids

What cleaves and breakesdown peptide chains in your body

Fibers on cribriform plate that detect smell

What in the nose detecrts smell

glucose

What is the sweetest carb

Brain, digestive system, and smell areas have taste receptors

what places in our bodies have taste receptors

Saliva is added to help lubricate food
Enzymes are released

• Salivary amylase (amylase also found in pancreas

• Lingual lipase (tongue lipid enzyme)

Chemical Digestion

Mainly mouth and stomach

where does digestion take place

Absorption takes place in intestine not stomach

Where does absorption take place

Only water and alcohol are absorbed in stomach

Whats absorbed in the stomach

The inactive form is pepsinogen and the enzyme that unfolds and breaks down complex protein peptides.

What does pepsin do and what is the inactive form

product of food mixing with stomach acid (gastric secretions)

What is chyme

HCl, Mucus (from goblet cells), pepsinogen, and hormone gastrin (causes stomach to contract)

What is secreted when food enters

sticky due to carbs (sugars) and protein in it

why is saliva and mucus sticky

30g of fiber

how much fiber do we need a day

determined by shape and structure

how is protein function determined

folding tissues in inner stomach (makes room by collapsing)

Gastric Rugae

Stomach and oral cavity

Where is Rugae found

3 mL of chyme squirted in intervals into small intestine

how much and how does food enter duodenum

When chyme goes thorugh pyloric spphinctor and into duodenum

Where does neutralization of stomach acid happen

Bicarbonate Ion from pancreas neutralizes stomach acid in the duodenum when it mixes with the chyme.

What neutralizes stomach acid in the duodenum

Villi

Microvilli

they both secrete digestive enzymes

what small structures assist in nutrient absorption

In the small intestine and increase SA, using villi and microvilli to increase absorption

where are Plicae circulares and what do they do

Proteins and Carbs. absorbed into villi and into bloodstream

what macronutrients are water soluble and where are they absorbed

Entrocytes

What are the cells of the intestine

Into lymphatic systemw

Where do lipids (fatty acids and glycerides) get absorbed

Jejunum

what part of the small intestine has the most absorption and digestion

neutralizes acidic chyme from stomach from pancreas

what does Alkaline bicarbonate do and where

fats

Gallbladder assists in digestion of _____

Lacteals and Then travel through lymph system

Fat and fat-soluble substances are absorbed into

Most minerals (NOT electrolytes)

whats absorbed in the Duodenum and upper jejunum

Carbs, amino acids, water soluble vitamins

whats absorbed in the Jejunum and upper ileum

Lipids and fat soluble vitamins

B12

whats absorbed in the Terminal segment the ilium

Little water, plant fibers (30g), indigestibles, bacteria

Digestive contents at terminus of ileum

Have phospholipids (like diglycerides with a phosphate group)

What do enterocytes have

Fatty acids (hydrophobic) flow right into them

Fat can also go down concentration gradients

How do fats get absorbed into enterocytes

Denatures proteins carrying nutrients and vitamins to unlock them

what does HCl do in stomach

acts as chaperone protein for B12

What does intrinsic factor do

Large Intestine

Where are the microbes that breakdown (Eat) fiber

12-24 hour

how long is normal transit time

Propulsion, absorption of water and sodium, prep of waste loss

Large Intestine functions

Produces 80% of body's Vitamin K and some B Vitamin

Ferments (breakdowns) fiber to short chain fatty acids (4-3 C chain)

What does bacteria in Large Intestine produce

Short chain fatty acids are #1 fuel source for intestine

SCFA strengthen Gap junctions between colonocytes and enterocytes
(links fiber to colon health)

What do Short chain fatty acids do for Intestine

In duodenum with pancreatic Amylase

Digestion of Carbs

• Maltose (Maltase)

  • Glucose + Glucose

• Lactose (Lactase)

  • Glucose + Galactose

• Sucrose (Sucrase)

  • Glucose + Fructose

What 3 enzymes digest disaccharides

always present on enterocytes (on microvilli)

(Usually they are secreted by pancreas but these are different)

where are maltase, Lactase, and Sucrase

transports dietary fats (only dietary fats) (through eating)

What does chylomicrons do

into lacteals of lymphatic system

Where do fats get transported