final part 2

constipation causes

ignoring urge to, diabetes, ibs, depression, pregnancy, medications, low fiber diet, age

inadequate enzyme production results in

incomplete digestion and limited absorption

causes of ulcers

infection w h.pylori and heavy use of NSAIDs

ulcerative colitis

inflammation and ulceration of the colon and rectum

Gastrointestinal hormones

key to orchestrating digestion

Sodium Bicarbonate

neutralizes acidic chyme

absorption in SI

ntr move from lumen into absorption cells in 4 ways

passive diffusion (4 ways)

nutrtients move form high concentration to low concentration

Heartburn and GERD

when stomach acid backflows into the esophagus (2x/week = gerd)

accessory organs

secrtions are delivered to SI through common bile and pancreatic ducts. those ducts come together at the end of the hepatopancreatic sphincter

dietary assessment

24 hour recall & food records

treatment for GERD

-Lifestyle changes → small frequent meals, eat upright, eat slowly, avoid spicy/v acidic foods -Surgery

Adequate Intake (AI)

-a recommended average daily nutrient intake level based on observed or experimentally determined estimates of nutrient intake by a group of healthy people -Insufficient scientific data to determine EAR and RDA Next best estimate of amount of nutrient needed to maintain good health -fiber, fat, linoleic acid, calcium, vit.D &K, Na,K,Cl,water

nutrients absorbed by the SI are delivered to 1/2 circulatory systems

-cardiovascular (water) -lymphatic (fat) * depends on the solubility of the nutrient

HCL

-destroys harmful bacteria and viruses -converts pepsinogen into active enzyme pepsin

ulcer symptoms

-gnawing or burning stomach pain -nausea -vomiting -loss of appetite -weight loss

Enterocytes of small intestine

-have a brush boarder lined with microvilli and covered wit digestive enzymes that contain GLYCOCALYX

Anthropometrics

-height, weight, length, waist circumference, body composition (lean mass and fat)

high energy dense foods

-high in fat, fried foods, sugar -small amounts = high cals

3 main functions of large intestine

-houses mircobiota( keeps GI healthy) -absorbs water and electrolytes (Sa, K) -forms and expels feces

stomach ; holding and mixing tank

-little digestion occurs -secretes gastric juices to aid in process(sensory reactions to food)

probiotics

-live microorganisms that colonize LI -found in fermented foods (yogurt,kefir,miso) and supplement -thought to prevents IBS, diahrrea, food allergies

stomach secretes music from mucous cells

-lubricates and protects stomach from being digested by Hlc and pepsin -production relies on prostaglandins

Tolerable Upper Intake Level (UL)

-max level of intake w/o causing adverse effects -chronic daily use -not a goal but ceiling -vit. A,C,D,E

Daily Reference Intake (DRI)

-new ntr recommendations to prevent deficients and chronic disease

Prebiotics

-non-digestable food ingredients, -promote the growth of beneficial bacteria insulin: ex. chicory, wheat, onions, garlic, asparagus, bananas

Endocytosis (4 ways)

-phagocytosis: cells eating compounds -pinocytosis: cells drinking liquids

RDA

-recommended daily allowance, meets needs of "all healthy people of similar age and gender" -19 impt ntr "generous allowances" -majority of ppl intake below -vit.A,C,D,E -thiamin, riboflavin,niacin, folate, b12 -copper, iodine, phosphorus, selenium, zinc, carbs, protein

sphincters

-ringlike muscles that control flow of contents and prevent them from moving too fast -help propel food

Glucose-dependent insulinotropic peptide (GIP)

-slow the release of chyme int the SI -stomach also produces intrinsic factor need for absorption of vit. b12

digestion starts in the mouth

-teeth: mechanical digestion -saliva: chemical digestion and creates bolus

hydrolosis reaction

-water breaking down molecules too large to pass through GI tract wall -stops simple molecules that are too small to be absorbed -most are produced in pancreas, SI, salivary gland and stomach -most are synthesized by pancreas and SI

3 sections of small intestine

1. Duodenum 2. Jejunum 3. Ileum

GI tract wall layers

1. mucosa - intermost 2.submucosa - connective tissue, blood vessels, nerves 3 muscularis externa - funcions to move foward 4.serosa - secretes fluid to cushion GI tract and reduce frictions

small intestine absorbs about

90% of water

fermentation

creates short chain FA that can be absorbed and used as energy source in the colon( produce gas)

Peristalsis

Involuntary waves of muscle contraction that keep food moving along in one direction through the digestive system.

estimated average requirements (EARs)

Nutrient intakes estimated to meet the needs of 50% of the healthy individuals in a given gender and life-stage group. -can only be set if theres accurate method for measuring whether intake is adequate

large intestine

SI empties in to LI through ileocecal valve (prevents bacteria in LI from going to SI)

Undernutrition

Too little food energy or too few nutrients to prevent disease or to promote growth; a form of malnutrition

gallstones

develop when cholesterol and bile pigments form crystal like particles -related to slow gall bladder motility and bile composition

ulcer treatment

antibiotics, proton pump inhibitor to suppress acid production, stop smoking, avoid ulcer prone foods

diarrhea is caused by

bacterial/viral infections, parasites, food intolerances, medications, vit.c, IBS

What does the liver produce?

bile

gastric juice contains

hydrochloric acid-from parietal cells, pepsinogin- inactive protein digesting enzyme gastric lipase - from chief cells gastrin- hormone that controles release of HCL and pesinogen

ulcer complications

bleeding and perforation

biochemical indices

blood and urine

proteases

break down proteins

Amalayse

breaks down starches

circular folds

cause chyme move slowly down a spiral path; this helps mix chyme w digestive juices and bring ntr to villi

Bile contains

cholesterol, emulsified fats

3 parts of LI

colon- cecum and ascending , transverse , descending and sigmoid colon rectum anus

energy density

comparison of kcal content with weight of food

nutrient density

comparison of vit&min content to number of cals

digestive system

digests foods, absorbs nutrients, excretes waste, acts as physical barrier, produces immune components houses microbiota, which is part of microbiome

pancreatic amylase

digests starch

large intestine is main site where

electrolytes are absorbed : sodium and potassium

Villi is lined with

enterocytes that secrete enzymes and absorb nutrients

Lysozyme

enzyme that kills bacteria

swallowing

esophageal sphincter prevents backflow of acidic stomach contents

overnutrtion

excessive nutrients that result in obesity or from supplements

nutrient density

few cals with lots of nutrients

treatments for constipation

fiber, intake of fluids, relaxation, exercise, medication(if necessary)

treatments for diarrhea

fluids, electrolytes, avoid high fat and sweet foods

GI motility

food is mixed and proposed by peristalsis , then segmentation occurs and breakdown in SI

diarrhea

frequent passage of loose, watery stools, 3x/day -caused by bacterial/viral infections, parasites, food intolerances, medications, vit.c, IBS

5 hormones in role of regulation

gastrin, secretin, CCK, somatostain, glucose:dependent insulinotropic peptide

interior of SI

has circular folds and finger like projections (villi and microvilli)

cardiovascular system

heart and blood, and vessels

when esophageal sphincter malfunctions

heartburn

GERD (gastroesophageal reflux disease) symptoms

heartburn, hoaseness, trouble swallowing, coughing, gagging and nausea

empty calorie foods

high in calories, low in nutrients

facilitated diffusion (4 ways)

high to low concentration BUT carrier protein is needed

digestion in Si also depends on secretions from the

liver, pancreas and gallbladder (accessory organs)

GI tract (aka Alimentary Canal)

long hollow muscular tube, 15 feet from mouth, pharynx, esophagus, stomach, small and large intestine to anus

active transport (4 ways)

low to high concentration area but requires protein carrier and energy

to prevent gallstone formation

maintain healthy weight, avoid rapid weight loss ,eat magnesium rich foods, plant protien high fiber diet exercise no sat fats

Gut Microbacteria

many of the bacteria is beneficial -can synthesize vit.K and biotin -aid in lactose digestion -ferment some fibers and starches

clinical examination

medical history and physical exam

IBS (no known cause)

more common in women irregular bowel function, ab pain and distention stress and diet play role

most individuals DONT have symptoms of gallstones but

pain in right ab, or sholder nausea vomitting gas bloating

pancreas produces

pancreatic juices

IBS treamemtn

peppermint oil, low fat, small meals

water soluble nutrients are transported by the CDV

protein, carbs, B vits, vit.c, short & medium chain fatty acids

lymphatic system

provides alternative route to the bloodstream for large molecules ex.) fat and fat soluble vits. (ADEK)

Adequate Macronutrient Distribution Range (AMDR)

range of macronutrient intake, as percent of energy, -associated with reduced risk of chronic disease while promoting recommended intake of essential nutrients

4 standards of the DRI

rda AI EARs ULS

only treatment for gallstones

removal

constipation

slow feces movement through LI, small indv nuggets(together) that're hard to pass

ulcers

small erosions of top layer of cells in the stomach or duodinum: peptic ulcer

major site of digestion and absorption

small intestine

reliance on empty cal foods

society w inexpensive, readily available, large portions of high energy dense foods

stomach contractions mix food w gastric secretions

solid food -> chyme

contributing factors to GERD

stomach hernias, alc use, overweight, smoking, pregnancy hormones and eating large meals, laying after eating ,caffeinated drinks, fried fatty/ spicy foods

gall bladder

stores and concentrates bile -bile is reabsorbed in the ileum and then returned to the liver

resistent starch

unprocessed whole grains, seeds, legumes , unripe fruit, pasta, potatoes and rice ex. fiber and butyrate

prostaglandins

use of asprin and other NSAIDs result in reduced mucus barrier and stomach wall may be damaged by HCL

"healthy" diet

variety(rainbow), balance( 6 major food groups), moderation (portion size)

low energy dense foods

water,fiber, wh, f&v, -associated with reduced energy intake and enhance satiety -can eat a lot w/o adding sig. cals

serios GERD complications

weight loss, ulceration, bleeding, anemia, and risk of adenocarinoma of esophagus