CARBOHYDRATES
Vocabulary
Simple Sugars:
Complex Carbohydrates:
Soluble Fiber:
Insoluble Fiber:
Amylase:
Insulin:
Glucagon:
Glycogen:
Hyperglycemia:
Hypoglycemia:
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WHAT ARE THE CARBOHYDRATES?
Organic compounds that contain CARBON, HYDROGEN, and OXYGEN in the ratio of 1
carbon atom and 1 oxygen atom for every 2 hydrogen atoms
• Two Main Classes:
• SIMPLE (sugars)
• COMPLEX (starches and fiber)
SIMPLE SUGARS
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MONOSACCHARIDES
Glucose (or Dextrose)
Galactose
Fructose
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DISACCHARIDES
Sucrose = glucose+
Lactose = glucose+
Maltose = glucose+
COMPLEX CARBOHYDRATES
POLYSACCHARIDES
• Starch - long chains of glucose molecules in straight (
) or branching (
arrangement
• Glycogen – animal form of starch (highly branched and composed of multiple glucose
molecules)
)
STARCH: Our bodies treat amylose and amylopectin the same. They are used differently in
manufacturing - example: cornstarch thickens products better than what flour because it has more
amylopectin. The branching creates a more stable product.
GLYCOGEN: After slaughter, the glycogen in muscle breaks down within 24 hours, so there is
no glycogen in this type of meat (organ meats are the exception). Glycogen is not important to us
as a carbohydrate source, but it provides energy for us in our bodies. Glycogen stored in the liver
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and muscle can be broken down into glucose and used as energy when needed. Normally, the
body can store about 200 to 500 grams of glycogen.
• FIBER – resembles starch, but cannot be digested
TYPES:
• Cellulose
• Hemicellulose
• Pectin
• Gums and Mucilages
• Lignans (is fiber, but not a polysaccharide)
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CLASSIFICATION of FIBER
SOLUBLE – dissolve in water
INSOLUBLE – cannot dissolve in water
Examples of each type:
Fiber Recommendations?
DIGESTION
• MOUTH
• STOMACH
• SMALL INTESTINE
• LARGE INTESTINE
ABSORPTION
• After absorption, all monosaccharides travel to the liver through the portal vein; once there
galactose and fructose are converted to glucose
CARBOHYDRATES in the BODY
USE OF GLUCOSE
• Energy – glucose is the primary fuel for most cells in the body. The brain MUST have
glucose!
• Sparing body protein – if glucose is scarce, the body will break down its own protein.
• Preventing ketosis – with no carbohydrate, fat breakdown produces ketone bodies. This can
lead to ketosis.
• Storage as glycogen – liver stores are used to maintain blood sugar, while muscle stores are
used to fuel activity.
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REGULATING BLOOD GLUCOSE LEVELS
• Insulin –
• Glucagon –
• Epinephrine –
GLYCEMIC INDEX
• Classifies food or meals based upon their potential to raise blood glucose levels
• Expressed as a percentage of the response to a standard carbohydrate, usually white bread or
pure glucose
• Useful? – decreased risk of NIDDM, heart disease, and colon cancer
• Useless? – complex, research may not support it
DIABETES
• Type I – Insulin Dependent Diabetes Mellitus (IDDM) or Juvenile Onset
• Type II – Non Insulin Dependent Diabetes Mellitus (NIDDM) or Adult Onset
RISK FACTORS
• Type I
• Type II
Diabetes – Acute Complications
• Hyperglycemia – with insufficient or ineffective insulin, blood glucose remains high.
Symptoms of hyperglycemia include:
• Intense thirst and/or hunger
• Increased urination
• Blurred vision
• Fatigue
• Acetone breath
• Labored breathing
• Ketone bodies are produced by the incomplete breakdown of fat when glucose is not available
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to the cells.
Accumulation of ketones in the blood is called ketoacidosis
The lungs must work hard to restore acid-base balance, and labored breathing and fatigue
result
Dehydration can be caused by fluid loss through the kidneys and osmosis
The most concerning acute complication is a coma
Diabetes- Chronic Complications
LONG-TERM CONSEQUENCES
• Peripheral vascular disease
• Deterioration of the eye
• Kidney disease
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• Progressive nerve damage
• Heart disease
Diabetes - Treatment
LOW BLOOD SUGAR - Hypoglycemia
• Arises from inappropriate management of diabetes
• Also from strenuous physical activity, skipped or delayed meals, inadequate food intake,
vomiting, or severe diarrhea
• Symptoms: hunger, headache, sweating, shakiness, nervousness, confusion, disorientation, and
slurred speech
• Left untreated, can lead to coma and death
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CARBOHYDRATES and HEALTH - Sugar
Sugar and nutrient intake: empty calories
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Sugar and dental caries: ex. baby-bottle tooth decay
Example – an orange versus sugar
CARBOHYDRATES and HEALTH – Complex Carbohydrates
A diet rich in complex carbohydrates lowers the risk of:
• Obesity
• Type II Diabetes
• Cancer
• Cardiovascular Disease
• Gastrointestinal Disorders
Specific Benefits of Dietary Fiber:
1. It has a positive impact on weight control because it delays gastric emptying and
enhances a feeling of fullness.
2. It improves glucose tolerance by delaying the movement of carbohydrates into the small
intestine.
3. It removes cholesterol by binding with bile in the intestine and causing it to be excreted.
4. It increases stool weight, thus promoting regularity.
5. It may protect against the development of colorectal cancer by decreasing transit time.
6. It decreases pressure within the colon.
NOTE: Fiber supplements provide fiber, but no nutrients.
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