nfmnt chapter 3 digestion, absorption, and utilization of nutrients
TRANSCRIPT
Nutrition Fundamentals and Medical Nutrition Therapy
Digestion, Absorption, and Utilization of NutrientsCorresponds with LEARNING PLAN 3Copyright 2016 Association of Nutrition and Foodservice Professionals
3
Objectives
Follow the path of digestion
Relate digestion to nutrition
Describe the organs involved in digestion
Differentiate between digestion of protein, fat, and types of carbohydrates
Discuss absorption and its relationship to other body systems
Explain the concepts of absorption and availability of nutrients
Nutrition Fundamentals and Medical Nutrition Therapy • Digestion, Absorption, and Utilization of Nutrients • Learning Plan 3
Follow the Path of Digestion
The digestive system» One of many ‘systems’ in our body» Organs body tissues cells » Specific cells perform specific functions» Organs work together as part of body systems
Nutrition Fundamentals and Medical Nutrition Therapy • Digestion, Absorption, and Utilization of Nutrients • Learning Plan 3
How the Digestive System Works
GI tract is made up of a 30’ long looped tube from mouth to anus
Digestion» Breaks food into smaller components» Converts components into nutrients» Eliminates solid wastes
Several organs involved in the digestive process» Smooth muscle layer helps food move through the tract
Nutrition Fundamentals and Medical Nutrition Therapy • Digestion, Absorption, and Utilization of Nutrients • Learning Plan 3
Brain Break
Identify the location of the organs involved in digestion.
Nutrition Fundamentals and Medical Nutrition Therapy • Digestion, Absorption, and Utilization of Nutrients • Learning Plan 3
Brain Break
Nutrition Fundamentals and Medical Nutrition Therapy • Digestion, Absorption, and Utilization of Nutrients • Learning Plan 3
Food is Broken Down During Digestion Mechanical breakdown
» Physical breakdown of food into smaller pieces- Chewing- 32 permanent teeth to grind and breakdown food
Chemical breakdown» Digestive enzymes chemical reactions breakdown of
complex nutrients
Nutrition Fundamentals and Medical Nutrition Therapy • Digestion, Absorption, and Utilization of Nutrients • Learning Plan 3
Path of Digestion
Mouth» Tongue and saliva form a bolus (mass of food)» Swallowing (from mouth to esophagus)
- Involuntary- Epiglottis prevents food from entering lungs
Esophagus» Lower Esophageal Sphincter (LES)
- Where acid reflux from the stomach can occur when the sphincter doesn't work properly
Nutrition Fundamentals and Medical Nutrition Therapy • Digestion, Absorption, and Utilization of Nutrients • Learning Plan 3
Path of Digestion
Stomach» Muscular contractions called peristalsis» Churns food into liquid consistency (chyme)» Alcohol and aspirin are absorbed
Small intestine» Chyme arrives through pyloric sphincter
Nutrition Fundamentals and Medical Nutrition Therapy • Digestion, Absorption, and Utilization of Nutrients • Learning Plan 3
Path of Digestion
Small intestines » 20’ long» Three parts
- Duodenum, jejunum, ileum
Nutrition Fundamentals and Medical Nutrition Therapy • Digestion, Absorption, and Utilization of Nutrients • Learning Plan 3
duodenumjejunum ileum
Brain Break
If a person no longer has a gallbladder, the digestion of what nutrient may be affected?
» Fat
Nutrition Fundamentals and Medical Nutrition Therapy • Digestion, Absorption, and Utilization of Nutrients • Learning Plan 3
Path of Digestion
Large intestine or colon» Extends from end of the ileum to the rectum» Water and some minerals absorbed here» Healthful bacteria is essential» Receives and stores waste products from digestion» Indigestible fiber attracts and holds water» Waste products released as solid feces through anus
Nutrition Fundamentals and Medical Nutrition Therapy • Digestion, Absorption, and Utilization of Nutrients • Learning Plan 3
Digestion of Nutrients
Carbohydrate» Mouth and small intestine
Protein» Stomach and small intestine
Fats» Small amount in mouth and stomach» Primarily in small intestine
Insoluble fiber» No digestive action
Nutrition Fundamentals and Medical Nutrition Therapy • Digestion, Absorption, and Utilization of Nutrients • Learning Plan 3
Absorption
Nutrients must pass from GI tract to circulatory system» Blood» Lymph
Metabolism» Anabolism – building substances» Catabolism – breaking down substances
Bioavailability of nutrients» How well nutrients are absorbed and used by the body
Nutrition Fundamentals and Medical Nutrition Therapy • Digestion, Absorption, and Utilization of Nutrients • Learning Plan 3
Brain Break
If a person has a GI illness, what might be a concern for the Certified Dietary Manager?
» The client may not be able to absorb nutrients adequately or bioavailability of nutrients may be decreased.
Nutrition Fundamentals and Medical Nutrition Therapy • Digestion, Absorption, and Utilization of Nutrients • Learning Plan 3