Ch26: Basic Nutrition & Cultural Considerations
GI Anatomy & Organ Fx
• GI System- mouth, tongue, teeth, pharynx, esophagus, stomach, small intestine, large
intestine, anus
• Accessor organs- salivary glands, liver, gallbladder, pancreas
• Mouth
o First part of digestive tract, contains teeth, tongue, receives secretions from
salivary glands
o Receives food, breaks it into small particles by chewing + mixing w/ saliva
o Assess color & condition of lips first when doing overall assessment
o Routine assessment during oral care: presence/condition of teeth, oral hygiene
practices
o Everyone must be able to chew, if not food changes need to be made
• Tongue
o Composed mostly of skeletal muscle, largest movable organ of mouth
o Manipulates food in mouth for chewing + mixing w/ saliva, helps position food
for swallowing, where taste buds located
o Check under tongue for lesions, open areas, Wharton’s ducts (submaxillary
ducts)
• Teeth
o Adults- 32 teeth, incisors/cuspids/bicuspids/molars
o Grasping, tearing, crushing, grinding food
o Ask pt to remove dentures during assessment if present, assess gums for lesions,
infx, etc
• Parotid glands
o Largest salivary gland, one on each side of body → anterior + inferior to ear
o Secretes saliva into mouth, saliva breaks down food, begin digestion of starches,
chewing stimulates saliva & digestive process
o Need adequate hydration for saliva production
• Pharynx
o Fibromuscular passageway connects nasal + oral cavities to larynx + esophagus,
food forced into pharynx by tongue
o Passageway for food to enter esophagus thru swallowing
• Esophagus
o Collapsible muscular tube 20 cm long, passageway for mvmt of food → stomach
o Lining of esophagus secretes mucus
• Stomach
o ULQ, 1.5 L capacity, 2 sphincters
o Temporary storage place for food
o Churning action of muscles of stomach mixes food w/ gastric juices
o Food changed to semiliquid state for passage to small intestine
o Gastric acids begin digestion of proteins
o Absorbs vit B12 thru action of intrinsic factor secreted from stomach wall
o Normal pH of stomach: 1.5-3.5
o S/s heart burn + acid reflux
o Assess meds r/t GI fx
• Small intestine
o Duodenum, jejunum, ileum
o Receives food from stomach and secretions from liver + pancreas
o Process of digestion is finished in small intestine
o Nutrients absorbed, residue passed to large intestine
• Large intestine
o Cecum, ascending colon, transverse colon, descending colon, sigmoid colon,
rectum, anus
o Site of absorption of f&e, elimination of waste products
• Liver
o RUQ
o Produces + secretes bile into small intestine for digestion of fats
o Plays major role in digestion of fats, carbs, proteins thru its metabolic fx
o How to assess liver:
o Stool depending on liver condition:
• Gallbladder
o Attached to surface of liver by cystic duct
o Stores & concentrates bile
o Fatty foods in duodenum stimulate flow of bile from gallbladder → duodenum
o How pt manages w/o complications after gallbladder removal
• Pancreas
o Along abd wall, head of pancreas on right side of duodenum, tail on left side next
to spleen
o Secretes digestive juices into small intestine for digestion of carbs, proteins, fats
o Secretes insulin for utilization of glucose
Changes in Digestive System w/ Aging
• Increased dental caries & tooth loss → decreased ability to chew food normally
• Decreased sense of taste & small → loss of appetite
• Decreased gag reflex → increased risk of choking + aspiration
• Decreased muscle tone at sphincters → increase heartburn or risk of esophageal reflux
• Decreased gastric secretions → interfere w/ food digestion
• Decreased peristalsis → increased risk of constipation or bowel impaction
Metabolism
• Process of large molecules broken down to smaller molecules
• Makes energy available to the organism
• Enables absorbed nutrients to enter bloodstream following digestion
o Digestion converts food into chemical substances such as proteins and simple
sugars to be used by the body for energy production and cellular metabolism
o US moved from agriculture-based economy to technology-based + sedentary life
style → factor in rising obesity rate in US
o Lack of physical activity & “couch potato” = reexamine metabolic needs
Dietary Guidelines: MyPlate
• Developed by USDA’s Center for Nutrition Policy and Promotion to promote healthy
diets for all Americans
• Shows 5 food groups necessary for good nutrition, explains use of each part
• Fruits, veggies, whole grains, fat-free or low-fat milk/milk products, lean meats, poultry,
fish, beans, eggs, nuts – need variety
• Low in saturated fats, trans fats, cholesterol, sodium, added sugars
• Half plate of food should be fruits + veggies, 3 main meals + 2 snacks/day, adjust
exercise level + food intake to maintain body wt w/n recommended limits, 8oz cooked
seafood recommended weekly
• Factors to consider for healthy diet: time + money
• Obesity + food insecurity (limited access to safe, nutritious food) found in low income,
Hispanic, African American, Native American, Asian/Pacific Island American community,
esp females – ethnic minorities
Protein
• Impt for rebuilding + replacing body tissues
• Helps maintain hormone production, fluid balance, antibody production, transportation
