NUTRITION

• Carbohydrates are organic compounds made up of Carbon (C), Hydrogen (H), and Oxygen (O)
• Carbohydrates are produced primarily by plants and provide approximately 4 kcal/g
• Carbohydrates can consist of varying numbers of sugar units
• Monosaccharides are carbohydrates made of a single sugar unit, while disaccharides are made of two sugar units
• Simple carbohydrates include blood glucose, fructose, and galactose
• Glucose is the most abundant monosaccharide and is used as a source of energy (ATP) for cells
• Fructose is a hexose sugar with a 5-sided ring structure
• Galactose is a monosaccharide found in lactose, the major carbohydrate in milk
• Disaccharides consist of two monosaccharides bonded together, such as sucrose (glucose + fructose), lactose (glucose + galactose), and maltose (glucose + glucose)
• Complex carbohydrates include oligosaccharides, polysaccharides like starch and glycogen, and fiber
• Oligosaccharides are composed of 3-10 monosaccharides and are found in beans and legumes
• Starch is a digestible polysaccharide that plants use to store glucose
• Glycogen is the storage form of carbohydrates in animals and humans, stored in the liver and muscles
• Fiber is a non-digestible polysaccharide crucial for good health, with soluble and insoluble types
• Soluble fiber sources include oats, barley, legumes, some fruits, and vegetables, while insoluble fiber is found in whole grains, nuts, seeds, and some vegetables
• Soluble fibers can slow gastric emptying, reduce serum cholesterol, improve appetite control, and normalize blood glucose levels
• Soluble fibers:

  • Slow gastric emptying and may delay absorption of some nutrients
  • Helps reduce serum cholesterol
  • Improve appetite control
  • Normalize blood glucose levels
• Insoluble fibers:

  • Relieves constipation
• Most plant foods contain both soluble and insoluble fibers
• Glucose:

  • Most important monosaccharides
  • All carbohydrates absorbed eventually become glucose
• Lactose:

  • Also known as milk sugar
  • Many people unable to break it down (lactose intolerance)
• Polysaccharides:

  • Strings of glucose molecules
  • Starch is found in food and is broken down during digestion
• Glycogen:

  • Storage form of carbohydrates in humans and animals
  • Stored in muscle and liver
• Fiber:

  • Carbohydrates that are not broken down and absorbed
• Carbohydrate Requirements according to Malaysian Dietary Guideline:

  • Carbohydrate: 55% - 75% of total energy requirement
  • Protein: 10-15% of total energy requirement
  • Fat: 15-30% of total energy requirement
• Major Roles of Carbohydrates in the Body:

  • Glucose supplies energy for the body
  • Primary fuel for most cells in the body and the preferred fuel for the brain, red blood cells, and nervous system
  • Storing glucose as glycogen in liver and muscles
  • Sparing body protein
  • Preventing ketosis
  • Food sweeteners include fructose, sucrose, glucose, maltose, and galactose
• How to Maintain Blood Glucose Levels:

  • Goal for blood glucose is 70 – 100 mg/dl
  • Glucose levels rise after a meal
  • Insulin lowers blood glucose levels by allowing glucose to enter cells and storing glucose as glycogen
  • Glucagon raises blood glucose levels by releasing glucose from glycogen stores
  • Diabetes mellitus is characterized by insulin deficiency or insulin resistance
• Glycemic Response:

  • Glycemic Index (GI) ranks foods based on their effects on blood glucose levels
  • Low-GI foods help control blood sugar levels and reduce insulin secretion
  • Factors influencing GI include sugar content, starch gelatinization, amylose to amylopectin ratio, protein and fat content, fiber content, and intact grains
• Glycemic Load:

  • Assess the overall glycemic effect of a diet based on GI and carbohydrate content per serving
• Carbohydrates and Health:

  • Sugar and Dental Caries
  • Fiber and Obesity
  • Fiber and Type 2 Diabetes
  • Fiber and Cardiovascular Disease
  • Fiber and Gastrointestinal Disorders
• Carbohydrate Digestion & Absorption:

  • Digestion breaks down food into smaller parts for absorption
  • Absorption involves transferring these parts into the blood for transportation
  • Starches must be broken down to yield glucose
  • Lactose intolerance results from insufficient lactase to break down lactose
• Complex carbohydrates:

  • Polysaccharides include starch, fiber, and glycogen
  • Oligosaccharides contain three to ten units and are part of cellulose in cell walls
• Factors which Influence the GI of a Food:

  • Sugar content
  • Starch gelatinization
  • Amylose to amylopectin ratio
  • Protein and fat content
  • Fiber content
  • Intact grains
• Discussion board link: https://padlet.com/mohdrahimi83/CHO_health_GTN104