Sugars, Starches, Fibres (12) Flashcards
What is meant by whole grain foods?
Those containing, “whole grain whole wheat flour including the germ” (not enriched)
Examples of complex carbs
Yam, whole grain bread/pasta, oatmeal, bananas, fresh berries, spinach
Examples of simple carbs
Donuts, candy, chocolate chip cookies, white bread, french fries
Simple sugars (+carbohydrates) refer to…
monosaccharides and/or disaccharides
Monosaccharides
-glucose (blood sugar)
-fructose (fruit sugar)
-galactose
…only product absorbed into bloodstream
What is an associated health risk with simple sugars?
-rapidly absorbed into the blood stream
-increase insulin resistance and inflammation
Disaccharides
-sucrose (cane/beet sugar, glucose + fructose)
-maltose (fermented for alcohol, glucose + glucose)
-lactose (milk sugar, glucose + galactose)
Complex carbohydrates
oligosaccharides (3 mono), polysaccharides (up to 1000’s mono)
Oligosaccharides
-short chains of monosaccharides joined by bonds that cannot be broken by human enzymes (source of fibre)
Examples of oligosaccharides
Garlic, onions, inulin
Polysaccharides
long chains of monosaccharides, some digestible some not
Examples of polysaccharides
potato, rice, pasta, corn, cereal, bread, apple peel, seeds, nuts
The 3 primary nutritional polysaccharides are?
- starch (energy storage in plants - digestible)
- glycogen (energy storage in animals - digestible)
- cellulose (structure in plants - nondigestible fibre)
What type of bond holds together starch and glycogen?
(digestible) alpha-glycosidic bonds
What type of bond holds together cellulose?
(non-digestible) beta-glycosidic bonds
Why is fibre important in the intestines?
-broken down into short chain fatty acids and gas in colon (feeds gut microbiota)
What attributes are present in good processed foods?
-few ingredients
-good to eat (whole wheat)
Ultra-processed foods
-significantly changed from its original state
-additional salt, sugar, fat, additives, preservatives, and/or artificial colors added
What are the characteristics of white flour?
-only the endosperm
-primarily starch (storage form of glucose in plants)
What components of the grain are present in whole grains?
-bran (outer layer, rich in dietary fibre)
-germ (protein, unsaturated fats, thiamin, niacin, riboflavin, iron)
-endosperm (starch)
soluble fibre
-slows down glucose absorption
-reduces fat and cholesterol absorption
-found in oats, barley, psyllium
-lower calories than digestible carbohydrates
Insoluble fibre
-moves bulk through gut
-controls gut pH
-removes toxic waste
-prevents constipation
-found in wheat bran, seeds, nuts
What does high blood glucose (from eating) stimulate?
Pancreas to release insulin
What does insulin do?
stimulates the uptake of glucose into cells (storage), converts excess glucose into fat stores
As cells use glucose, blood glucose levels decline resulting in…
pancreas releasing glucagon
What does glucagon do?
stimulates liver cells to break down glycogen and release glucose into the blood
Which nutrient has the largest effect on blood glucose?
Carbohydrates- peak fast, and large impact
3 downsides of sugar intake
1) tooth decay
2) empty calories (no nutrients)
3) often mixed with fatty foods
Non-nutritive sweeteners
zero (or low) calorie sweeteners that are either artificially synthesized or naturally derived
Sugar Intake Recommendations: women
no more than 100 calories per day (24 grams)
Sugar Intake Recommendations: men
no more than 150 calories per day (36 grams)
Sugar Intake Recommendations: children
less than 24 grams per day (limited to no more than 8 ounces a week of sugary beverages)
One can of coke (10 tsp of sugar)
exceeds daily amount for women, men, and children
Alcohol sugars
-xylitol, mannitol, sorbitol
-used in chewing gum
-not well absorbed in gut (large amounts cause diarrhea)
Stevia
-herbal alternative (GRAS)
-initially rejected, then approved
Aspartame
-aspartic acid + phenylalanine
-200x sweeter than sugar (sucrose)
-NOT compatible with high temperatures (>30 degrees)
Sucralose
-“splenda”
-600x sweeter than sugar
-safe when heated
-chlorinated sugar
Acesulfame K
-often combined with other artificial sweeteners
Saccharin
-accidently discovered by chemist working on coal tar derivatives
-banned, then returned to market
Should artificial sweeteners be used as a method of weight control?
No, with the exception of people with diabetes
How does sugar contribute to tooth decay?
-bacteria feeds on sugar (produces acid)
Which products contribute to tooth decay?
-increased frequency of sticky foods
-acidic beverages
-excessive cleaning/polishing of teeth
-nursing bottle syndrome (fall asleep w/ bottle in mouth)
Protective foods
-cheese (increases pH of plaque, decrease acidity)
-protein (w/ calcium it strengthens enamel)
-low calorie sweeteners (sorbitol, mannitol, xylitol… stimulates saliva)
Fluoride
-promote remineralization of eroded enamel
-in city water, toothpastes, dental rinses
fluorosis or “mottled” enamel
-cosmetic condition in children under 8 years (where permanent teeth are developing)… white spots
