intro nutr y dietetica 281009
Post on 07-May-2015
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• Simple CHO= monosaccharides (single sugars): – fructose {fruit} – glucose {BS/Glu} – galactose {milk}
• Other simple CHO are pairs of sugars called disaccharides: – lactose {milk}= composed of one molecule of glucose &
one molecule of galactose– maltose {malt- product of starch digestion}= composed
of 2 glucose molecules– sucrose {table, beet, cane}= one molecule of glucose &
one molecule of fructose
• Oligosaccharides- short CHO chains of 3-10 sugar molecules
• Polysaccharides- strands of many sugars & most are classified as Complex CHO – starch, granules, glycogen, & fiber– Note: their names are characteristic of their
chemical make up
• Starch is a plant polysaccharide composed of glucose; once cooked= easily digestible
• Glycogen is a polysaccharide [not considered a complex CHO] composed of glucose, made & stored in the liver & muscles
• Note: Glycogen is the storage form of glucose in animals, including humans; when eaten in excess, stored as fat
• High CHO foods:– High in complex CHO• Bagels• Tortilla• Cereals• Crackers• Legumes• Potatoes• Peas • Popcorn
• High CHO foods:– High in simple CHO [naturally]• Fruits• Fruit juices• Skim milk• Plain nonfat yogurt
– High in simple CHO [added]• Angel food cake• Soft drinks {known as liquid candy; yields}• Sherbet• Candy• Jams, etc. {refer to text for more examples}
• Fiber is known to lower cholesterol, aid with elimination by decreasing constipation, reduce risk for colon cancer & diverticulosis
• Cellulose is the best known form of fiber.– Provides roughage which aids in digestion and elimination.
CANNOT be broken down by digestive enzymes.• Insoluble fiber does not dissolve in water
– Veggies, fruits, grains • Soluble fiber readily dissolves in water, may be gummy or
gel-like– Barley, rye, pectin
• Only plant foods contain dietary fiber
• Foods rich in dietary fiber include:– Fruits (apples, bananas, grapefruit, pears)– Vegetables (asparagus, broccoli, carrots,
spinach, red cabbage)– Nuts and Seeds (almonds, peanuts, walnuts)– Legumes (most all)– Grains (brown rice, oat bran, oatmeal, whole-
wheat breads, wheat-bran cereals)
• Lactose intolerance is seen in about 75% of people as they age because: • Lose the ability to produce enough of
the enzyme lactase (made in the small intestines) to digest the milk sugar lactose• nausea, pain, diarrhea, & excess
flatulence result
• Ketosis is the unusual breakdown of fat (ketone bodies) which accumulates in the blood & disturbs acid-base balance. – This stems from using fat w/o the help of CHOs.
• The body needs a minimum of 50-100 grams of CHO per day to prevent ketosis.
• Insulin- hormone released after the pancreas is notified by the body that glucose is in the blood stream
• When the blood glucose concentration drops & cells need energy, a pancreatic hormone, glucagon, floods the bloodstream which stimulates the liver to release glucose – Important: The body cells use what glucose
they can for energy.
• Excess glucose is linked together & stored as glycogen until the muscles and liver are full to capacity w/ glycogen; but– If glucose keeps coming, the liver has no choice
but to handle the excess.
• Classifies foods or meals based on their potential to raise blood glucose levels. – Expressed as a % of the response to a standard food or CHO,
usually white bread.• Foods with a high glycemic index trigger a sharp rise in
blood glucose, followed by a dramatic fall.• The type of CHO, the cooking process, and the presence
of fat and dietary fiber all affect a food’s glycemic index. • Body copes with low glycemic foods easier b/c of slower
and more modest changes in blood glucose levels.– Candy (Jelly Beans)= 78– Fruits (apples)= 38
• Current evidence has shown that moderation is the key.
• When it comes to artificial sweeteners, they pose no known health risk; but the jury is still out.
• There is a lot on controversial research out there. One thing is known is that it is safer for teeth than regular CHO sweeteners
• It has been stated that artificial sweeteners convert to formaldehyde & can be linked to cancer
• Saccharin– Derived from coal tar– 300-500x sweeter than sugar– Pink package- Sweet N Low– Research has linked saccharin to cancer in
laboratory animals
• Aspartame– Contains two amino acids- aspartic acid (non-
essential type) + phenylalanine (essential)– 180x sweeter than sugar– Not recommended for cooking b/c flavor changes
with heat– Blue package- Equal– Researchers believe this one to be safe, some
concerns and side effects noted
• Splenda– Derivative of sugar– Comprised of dextrose, maltodextrin, and
sucralose– Newest on the market– Yellow package– Believed to be safe
• Stevia– 300x sweeter than sugar– Taken from herbs and shrubs (leaf)– Stevia was approved for use by FDA in late 2008
and now appears in Coca-Cola & Pepsi products like SoBe life water
– Truvia (Rebaudioside A) commonly known sweetener
• They have little to no nutritional value• Nutritive Sweeteners (digestible CHO)- have
calories– White sugar– Brown sugar– Maple sugar– Honey, etc.
• FDA set a maximum allowable intake for aspartame of 50 mg/kg – (Aspartame contains phenylalanine and aspartic
acid)– Equal to: 16 12-ounce diet sodas (adults) and 8
12-ounce diet sodas (children)
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