Chapter 4 Flashcards
Carbohydrates Composition
Composition: Carbohydrates are composed of carbon, hydrogen, and oxygen. They provide about 50% of the energy used by muscles and body tissues.
Carbohydrates Types
Types: Include sugars, starches, and fibers. Carbohydrates are classified as monosaccharides, disaccharides, and polysaccharides.
Glucose
Monosaccharides (Single Sugars):
Glucose: Blood sugar, essential for energy.
Fructose
Monosaccharides (Single Sugars):
Fructose: Sweetest sugar, found in fruits, honey, and high-fructose corn syrup.
Galactose
Monosaccharides (Single Sugars):
Galactose: Found in few foods.
Maltose
Disaccharides
Maltose: Glucose + glucose, found in barley.
Sucrose
Disaccharides
Sucrose: Glucose + fructose, found in fruits, vegetables, and refined for table sugar.
Lactose
Disaccharides
Lactose: Galactose + glucose, found in milk.
Glycogen
Polysaccharides
Glycogen: Storage form of glucose, stored in the liver and muscles.
Starches
Polysaccharides
Starches: Plant polysaccharides made of glucose units (e.g., wheat, rice, potatoes).
Fibers
Polysaccharides
Fibers: Structural parts of plants, not digestible by human enzymes.
Soluble fibers
Dietary Fibers:
Soluble fibers: Dissolve in water, form gels (e.g., pectin from fruit), beneficial for heart disease, diabetes, and weight management.
Insoluble fibers
Dietary Fibers:
Insoluble fibers: Do not dissolve in water (e.g., celery strings), promote GI health.
Resistant starches
Resistant starches: Not digested in the small intestine, may have health benefits.
FODMAP
FODMAP: Poorly digested carbohydrates that may cause GI symptoms; a FODMAP diet can help treat IBS.
Irritable bowel syndrome (IBS)
Carbohydrate Digestion:
Begins in the mouth with salivary amylase, and continues in the small intestine with pancreatic amylase.
Lactose Intolerance:
Lactase activity decreases with age, causing symptoms like bloating and diarrhea.
Management: Include small amounts of dairy, consume fermented milk products, and be cautious of lactose in non-dairy foods.
Glucagon/Epinephrin
Blood Glucose Regulation:
Glucagon/Epinephrine: Raises blood glucose by breaking down glycogen.
Insulin
Blood Glucose Regulation:
Insulin: Lowers blood glucose by moving it into cells.
Glycemic Response:
Refers to how much and how quickly a food raises blood sugar levels.
Health Effects of Sugars:
Excessive sugar intake is linked to obesity, chronic diseases, and dental caries.
Recommended Intakes:
Sugars: Less than 10% of energy intake.
Carbohydrates: 45-65% of total energy intake, 130 grams/day.
Fiber: 25 grams/day for females, 38 grams/day for males.
Health Effects of Starch and Fibers:
Beneficial for heart disease, diabetes, cancer prevention, GI health, and weight management.
