Nutrition ch 4-6 Flashcards
What is a whole grain?
contain all of the essential parts (starchy endosperm, germ, and bran) of the entire grain seed in its original proportions. Dietary Guidelines for Americans advise half of the grains consumed should be whole grains.
Beneficial nutrients and phytochemicals are found in the bran and germ
what is an enriched grain?
cereal grains that lost nutrients during processing but have vitamins and minerals added back in; refined grains are often enriched.
What are the four functions of carbs in the body
The energy source for red blood cells, Important for intestinal health, reduces the use of protein for energy, energy for physical exertion and for the brain.
Define Disaccharide
a carbohydrate that consists of two sugar molecules; for example, maltose, sucrose, and lactose. simple carb
define Monosaccharide
a carbohydrate that consists of only one sugar molecule; for example, glucose, fructose, and galactose. simple carb.
Only monosaccharides can be absorbed by cells of the small intestine.
Where can these monosaccharides be found; fructose, glucose and galactose?
fructose and glucose(most abundant) can be found in fruit,veg and honey. They are converted to glucose by the liver.
Galactose is one of the monosaccharides that makes up milk sugar(lactose) the other is glucose.
What is the most abundant monosaccharide in our diet?
Glucose-it is part of all disaccharides, starches, and many fibers.
What are oligosaccharides
a short-chain carbohydrate that consists of 3–10 monosaccharide units joined together.
What are polysaccharides
Chains (or polymers) of more than 10 monosaccharides.
a long-chain carbohydrate that consists of more than 10 monosaccharides joined together; tend not to have a sweet taste (unlike monosaccharides and disaccharides) and can be found in foods such as whole grain breads, dried beans, and starchy vegetables.
What is fiber
carbohydrates that include cellulose and hemicellulose, which make up plant cell walls and impart structure to the plant; humans lack the digestive enzymes to break down plant fiber, so it passes undigested through the digestive tract.
What are starches
complex carbohydrates that are abundant in grains, legumes, and starchy vegetables; they consist of long chains of glucose joined together by digestible bonds; examples include amylose and mylopectin.
What is glycogen
a polysaccharide consisting of many glucose molecules; acts as the storage form of glucose (carbohydrate) in animal tissues (liver and muscles).Liver breaks down glycogen into glucose. Glycogen is broken down into glucose muscles for exercise.
Anatomy of grains-endosperm
Endosperm the element of a grain that contains the highest amount of starch and protein; this is all that remains when grain is refined.The endosperm is surrounded by nondigestible fibrous bran. It needs to be crushed,cracked, milled etc to expose the endosperm.
Where is amylase found and what does it break down?
Amylase breaks down starch molecules into shorter polysaccharides from salivary glands in the mouth.
Salivary amylase is inactivated by gastic acid and starch digestion stops.
In the small intestine, pancreatic amylase digests starch into oligosaccharides and maltose.
What is lactose intolerance
Low production of lactase in the intestines.
a disaccharide sometimes called “milk sugar,” as it is found only in milk, yogurt, and other dairy products; it is made up of glucose and galactose.
What hormone does the pancreas secrete to signal for tissue to take up glucose from the blood?
Insulin-skeletal muscle, cardiac muscle, and adipose tissue take up glucose from the blood. Signals muscles and liver to store as the polysaccharide glycogen or glucose into fat.
What is glucagon
A hormone released by the pancreas signals liver cells to release glucose into the blood to maintain blood glucose levels-release hours after eating.
Describe the four enzymes that break down carbs. Where are they and what do they break down
Amylase: digests starch into oligosaccharides and maltose. Saliva and sm. intestine.
Maltase: breaks down maltose into two glucose unites
Sucrase:digests sucrose into fructose and glucose
Lactase: Breaks down lactose into glucose and galactose. Absorbed by cells in sm. intestine
What is resistant starch?
Starch that is partially “trapped” in the physical structure in the internal portion of larger food particles. These structures can make it difficult for digestive enzymes to gain access to the starch, slowing digestion and the subsequent appearance of glucose in blood. It may improve our responsiveness to insulin and help feel full longer. Beans, underripe bananas, whole grain kernels, and pasta. Sucrose,lactose and fructose foods such as candies,dairy foods and fruit ofen produce a less dramatic rise in blood glucose then do starchy foods. This is because fructose and galactose have no immediate impact on blood glucose levels until they are covered to glucose in the liver.
Name the variety of names for added sugars
brown sugar, corn sweetener, dextrose, fructose, fruit juice concentrate, glucose, honey, invert sugar, lactose, maltose, molasses, raw sugar, sucrose, table sugar and high fructose corn syrup.
How does high fructose corn syrup differ from other sugars?
Its ratio of sucrose to glucose is 55% instead of 50%
What health issues do added sugar cause?
It contributes to about 13% of total calories for most Americans. Sugar creates additional calories without fiber or nutrition which contributes to obesity and cavities.
What are the two types of sugar alternatives?
Nutritive: Include polyols-alcohol forms of sugars sorbitol(from glucose), mannitol(mannose) made from sugars in plants, poorly absorbed by the body less then 4kcal per gram. Excessive consumption of sugar alcohol cause gastrointestinal symptoms including diarrhea.
Non nutritive: Aspartame made by linking two amino acids together (nutrasweet and equal). It is 200x sweeter then sucrose.
Stevia, Splenda(sucralose) and Sweet’n Low (saccharin)
The health and medicine division recommends how much fiber
38 grams for men and 25 grams for women under 50.
What is the difference between soluble and insoluble fiber?
Insoluble does not disolve in water and typically poorly fermented passes through gi mostly intact.
Benefit-soften stools and maintains reg BMs, reduce risk of hemorrhoids and diverticular disease.
Soluble fiber dissolves in water and easily fermented(broken down) by bacteria in the colon. whole grain oats,barley, rye citrus fruits legumes Mangos avocados pears apples psyllium Benefits-decrease risk of diabetes and coronary heart disease. Slow the emptying of food from the stomach into the small intestine which extends fullness following a meal.Slow digest and absorption and reduce rise of blood glucose following carb meal-beneficial for diabetics.
Both fibers:reduce cancer risk, more likely to be nutrient dense and lower in sat.fat, sodium and added sugar.
What is the difference between dietary fiber and functional fiber?
Dietary fiber-undigestible carbs that are present naturally in intact plant foods
Subtract fiber from total carbs to determine the amount of carbs that can be digested and absorbed.
Functional fiber is nondigestible carbs that have been added to a food product and have health benefits that are similar to those of dietary fiber.
Psyllium husks and Pectin from fruit.
When you add dietary fiber and functional fiber you get its total fiber
What does the FDA require added fiber to do?
Demonstrated to have at least one beneficial effect such as lowering blood cholesterol or improving bowel function.
A food label cannot display the 100% whole grain stamp if_____wheat germ has been added to the food.
Wheat germ
What role does the pancreas play?
Delivers digestive enzymes and regulating the body’s levels of blood glucose
What are the two types of diabetes and what happens in the body?
Type 1- autoimmune disease characterized by the destruction of insulin-producing cells in the pancreas pancreas does not produce enough insulin for blood glucose control
Type 2- specific tissues become resistant to the effects of insulin
Diabetes is an overload of glucose in the blood causing vascular(blood vessel) damage that can lead to serious and often fatal complications.
Hyperglycemia begins when fasting blood glucose concentrations are
100 mg/dl or greater
The number one killer for diabetes is
heart disease
What is the glycemic Index
Ranking of foods by how quickly and to what degree they raise blood glucose levels.
Low GI foods cause a smaller and more gradual increase
High GI foods create fast spikes