Chapter 4 Flashcards
What are the 3 general categories of carbohydrates in our food?
Unrefined (Whole) Carbohydrates, Refined Carbohydrates, Enrichment
What are Unrefined Carbs?
Carb sources eaten in their natural form (Minimal processing)[ex. Corn]
What are Refined Carbs?
Processed carbs(Empty calories; low nutrient density) [Ex cereal]
What are Enriched Carbs?
Some nutrients fortified back into food after it was lost in processing.
Define Whole Grains?
Unrefined carbs; include entire grain kernel.
What is found in a whole grain kernel?
Germ(Oil, Vitamins), Bran(Fibre, Vitamins, Minerals), Endosperm(Primarily Starch)
What part of the grain kernel do refined carbs contain?
Only the endosperm.
What unit makes up sugars, starches and fibres?
Sugar units
What are the 3 types of sugar units?
Monosaccharides(Single unit), Disaccharides(2 units), Polysaccharides(3+ Units;Starches, Fibres;Complex carbs)
What sugar unit must carbs be in, inorder to be absorbed?
Monosaccharides
3 sugars that are monosaccharides?
Glucose(in blood), Fructose(fruits), Galactose(milk)
3 sugars that are disaccharides?
Maltose(Glucose+Glucose), Sucrose(Glucose+Fructose), Lactose(Glucose+Galactose)
Define Added Sugar?
Chemically similar to natural sugars, but have no nutritional benefit. (Empty calories)
Common examples of food that contain added sugar?
Cookies, pop, candy
Diseases or problems associated with too much added sugar?
Cardiovascular disease, Obesity, diabetes, Addictive food tendencies, Dental caries, acne
Define Complex Carbs?
Polysaccharides; generally not sweet
Can Fibre be absorbed in the small intestine?
No, as the SI lacks the enzymes to absorb fiber.
Define Soluble FIber?
Able to be broken down in the Large intestine by bacteria.(form short chain fatty acids)(Gives 2-3 kcal/g)
Define Insoluble Fibre?
Does not provide energy for body.
Which type of fibre dissolves in Water?
Soluble
Sources of soluble fiber?
Oats, Apples, Nuts, Beans, Seaweed, Jams
Sources of insoluble fibre?
Whole wheat, Rye, Bran, Broccoli, Celery
Benefits of soluble fibre?
Promotes heart health. Helps regulate blood glucose levels and binds cholesterol containing compounds.
Benefits of insoluble fibre?
Promotes intestinal health. Speeds passage through intestines, binds toxic waste products, promotes regular bowel movements, prevents constipation.
How are carbohydrates broken down?
Salivary amylase in the mouth(polysaccharides), Pancreatic amylase in the SI(disaccharides), enzymes attached to microvilli in Large Intestine, fibre broken down by bacteria in LI
How are carbs absorbed?
Monosaccharides travel from capillaries of SI to liver, Glucose sorted as glycogen in liver or used for energy or delivered to body tissues, galactose and fructose used as energy.
Define the Glycemic Response?
Measure of how quickly blood glucose levels rise after a carb rich meal (Refined sugars cause higher glycemic response)
Define Glycemic Index?
Relative ranking of how a food affects blood glucose relative to the effect of an equivalent amount of carbs from a reference food.
What happens when blood glucose levels rise?
Pancreas releases insulin, which causes; 1) Glucose to be stored in liver as glycogen 2) Enters fat storing cells 3)Enters muscle tissue cells for them to use in Cellular Respiration; Blood glucose levels lower
What happens when blood glucose levels lower?
Pancreas releases glucagon into liver, glycogen converted to glucose in liver, which is released into blood; Blood glucose levels rise.
Define Lactose Intolerance?
Levels of lactase(enzyme) are naturally low, meaning lactose sugar can’t be broken down in SI. Pass into large intestine where they are digested by bacteria producing methane gas.
3 Functions of Carbohydrates?
Glucose as energy, ‘spare’ protein, promote Fatty Acid metabolism
Define Glucose as a source of energy?
Process of cellular resp, each g glucose = 4 kcal energy
Define carbs ‘spare’ protein/ gluconeogenesis?
Carb levels insufficient, glucose can be synthesized from amino acids. This uses up body proteins(muscle).
Eating enough carbs spares body protein.
Define carbs promote FA metabolism?
Need carbs to fully metabolize fats.Carbs form oxaloacetate which reacts with acetyl CoA in krebs cycle.
Explain “Fats burn in a carb flame”/ Ketone formation?
No oxaloacetate, fat forms ketone bodies. High levels of ketones= ketosis. Can result in reduced appetite, odd-smelling breath, dry mouth, headaches, flu like symptoms.
Diabetes and Diabetes in Canada?
High blood glucose. Affects 2 million Canadians. Higher in Aboriginal and Hispanic populations. Long periods of high blood glucose levels lead to nerve,kidney,blood vessel damage.
Define Type 1 Diabetes?
Auto immune disease, where immune system attacks pancreatic cells that secrete insulin. Uncontrolled can lead to ketoacidosis(death and coma). [5-10% cases]
How Type 1 Diabetes is managed?
Regular injections of insulin.
Define Type 2 Diabetes?
Insulin resistance. Preventable as its lifestyle related. Begins with pre-diabetes.[90-95% cases]
How Type 2 Diabetes is managed?
Weigh Management, limit carbs + saturated + trans fat, exercise, medication, gastric surgery.
What are the symptoms of diabetes?
Frequent urination, thirst, weight loss, blurred vision, blindness, kidney failure, nerve dysfunction, increased risk of infection(amputation), dementia?
What is Gestational Diabetes?
Elevated blood glucose during pregnancy, passed to fetus. Mother and offspring higher risk for T2 Diabetes and obesity.
Define Hypoglycemia?
Low blood sugar. Fasting; occur in absence of food Reactive; Occur in response of consumption of high car foods.
Symptoms of Hypoglycemia?
Irritability, sweating, shakiness, anxiety, rapid heartbeat, seizures, coma
How Carbs and Weight Management Relate?
Low carb diets may promote weight loss b/c high protein/ fat diets are more satisfying therefor less calories are consumed.Refined carbs less satisfying. Unrefined carbs higher in fiber and more satisfying.
Heart Disease and Carbs?
Risk depends on type of carb, high sugar diets raise blood lipid levels + LDL bad cholesterol. High fiber diets reduce risk.
How to meet carb needs?
AMDR= 45-65%, 130g/day meets energy needs, AI for fiber men=38g/day women=25g/day. Sugar UL =10% daily calories. Emphasis on whole grains.
