Authors: Linda Debruyne, Kathryn Pinna
Edition: Seventh Edition
Source: © 2020 Cengage. All rights reserved.
Identify Carbohydrates:
Monosaccharides, disaccharides, polysaccharides, and their food sources.
Digestion and Absorption:
Summarize how carbohydrates are digested and absorbed in the body.
Blood Glucose Control:
Explain the role of hormones in regulating blood glucose levels.
Health Problems Related to Sugars:
Describe health issues from added sugars and the role of alternative sweeteners.
Health Benefits of Starches and Fibers:
Identify benefits and recommendations regarding starches and fibers.
Glycemic Index:
Discuss the glycemic index and its controversial role in disease prevention.
Energy Source:
Carbohydrates are essential for energy, especially for the brain.
Recommended sources include grains, vegetables, legumes, fruits, and milk.
Sugars:
Monosaccharides: Single sugars (e.g., glucose, fructose, galactose)
Disaccharides: Two linked sugars (e.g., sucrose, lactose, maltose)
Polysaccharides: Chains of monosaccharide units (e.g., starch, glycogen, fibers)
Glucose:
Key energy source, particularly for the brain and nervous system.
Fructose:
Found in fruits, honey; sweetest sugar.
Galactose:
Part of lactose, found mainly in milk.
Sucrose:
Composed of glucose and fructose (table sugar).
Lactose:
Made of glucose and galactose (milk sugar).
Maltose:
Contains two glucose units; formed during starch breakdown.
Major Types:
Glycogen: Stored in muscles and liver; serves as energy reserve.
Starch: Plant-derived energy storage; major carbohydrate in diet.
Fibers: Indigestible components of plant cell walls; beneficial for digestion and health.
Soluble Fibers:
Dissolve in water; help lower cholesterol and glucose absorption.
Sources: oats, fruits, legumes.
Insoluble Fibers:
Do not dissolve; promote fecal bulk and help prevent constipation.
Sources: whole grains, vegetables.
Process Overview:
Goal is to break down carbohydrates into monosaccharides for absorption.
Digestive Pathway:
Saliva in the mouth begins breakdown with enzymes.
Stomach halts carbohydrate digestion.
Pancreas releases enzymes in the small intestine to further digest carbs.
Monosaccharides absorbed by intestinal cells.
Fiber:
Not digested but beneficially alters nutrient absorption and digestion speeds.
Insulin and Glucagon:
Hormones that maintain blood sugar levels; insulin lowers and glucagon raises blood glucose.
Obesity and Heart Disease:
High added sugar intake linked to obesity and lipid buildup in arteries.
Dental Health:
Sugars promote cavity-causing bacterial growth.
Moderation is Key:
Limit added sugars to less than 10% of total caloric intake; ideally less than 5%.
Sugar Alcohols:
Provide fewer calories than sugars; beneficial in sugar-free foods.
Nonnutritive Sweeteners:
Provide sweetness without calories; some concerns exist regarding long-term health effects.
Increase Fiber Intake:
Promote whole grains, legumes, fruits, and vegetables for overall health.
Limit Excessive Fiber:
Can interfere with nutrient absorption and create digestive issues.
Definition:
Measures absorption speed of carbohydrates; informs dietary choices for blood sugar management.
Considerations:
Low-GI foods may reduce chronic disease risk; however, more research is warranted.
Balanced Diet:
Carbohydrates should comprise 45-65% of daily caloric intake; focus on healthy sources.
Food Sources:
Include grains, fruits, vegetables, and legumes to ensure adequate carbohydrate and fiber intake for health benefits.