Nutrition: Chapter 4: Carbrohydrates: Sugars, Starches, and Fibers

Glucose

A 6-carbon monosaccharide that is the primary form of carbohydrate used to provide energy in the body; blood sugar; most important carbohydrate for the human body.

Starch

A carbohydrate found in plants, made up of many glucose molecules linked in straight or branched chains.

Monosaccharide

A carbohydrate made up of a single sugar unit.

Polysaccharide

A carbohydrate made up of many sugar units linked together.

Disaccharide

A carbohydrate made up of two sugar units.

Diverticulosis

A condition in which outpouches (or sacs) form in the wall of the large intestine.

When does a low-carbohydrate promote weight loss?

A diet high in unrefined carbohydrates is high in fiber, which is filling, allowing you to feel satified with less food. This can help promote weight loss.

Diabetes Mellitus

A disease characterized by elevated blood glucose due to either insufficient production of insulin or decreased sensitivity of cells to insulin.

Autoimmune Disease

A disease that results from immune reactions that destroy normal body cells.

Insulin

A hormone made in the pancreas that allows glucose to enter cells and stimulates the synthesis of protein, fat, and liver and muscle glycogen.

Glucagon

A hormone made in the pancreas that raises blood glucose levels by stimulating the breakdown of liver glycogen and the synthesis of glucose.

Sugar Unit

A sugar molecule that cannot be broken down to yield other sugars.

Hypoglycemia

Abnormally low blood glucose levels.

Ketones or Ketone Bodies

Acidic molecules formed when there is not sufficient carbohydrate to completely metabolize the acetyl-CoA produced from fatty acid breakdown.

How does fiber benefit colon health?

Add bulk and absorb water in the GI tract, making the feces larger and softer and reducing the pressure needed for defecation.

What process breaks down glucose in the presence of oxygen to yeild ATP?

Aerobic Metabolism

Glycolysis

An anaerobic metabolic pathway that splits glucose into two three-carbon pyruvate molecules; the energy released from one glucose molecule is used to make two molecules of ATP.

How does fiber affect glycemic response?

Because fiber takes longer to leave the stomach and slows absorption in the small intestine, fiber-containing foods cause a lower glycemic response.

Prediabetes

Condition in which glucose levels are above normal but not high enough to be diagnosed as diabetes.

What health problems are common in people with uncontrolled diabetes?

Damage to the heart, blood vessels, kidneys, eyes, and nerves.

What steps are involved in starch digestion?

During digestion, enzymes break starches and sugars into monosaccharides, which are absorbed. Most of the fiber and other indigestible carbohydrates are excreted in the feces.

Gestational Diabetes

Elevation of blood sugar that is first recognized during pregnancy.

Empty Calories

Energy with few additional nutrients.

Soluble Fiber

Fiber that dissolves in water or absorbs water and can be broken down by intestinal microflora. It includes pectins, gums, and some hemicelluloses.

Insoluble Fiber

Fiber that, for the most part, does not dissolve in water and cannot be broken down by bacteria in the large intestine. It includes cellulose, some hemicelluloses, and lignin.

Unrefined Foods

Food eaten either just as they are found in nature or with only minimal processing, such as cooking.

How do enriched grains differ from whole grains?

Foods made with refined grain contain more of some nutrients and less of others than foods made from whole grains.

Which monosaccharide circulates in the blood?

Glucose is a monosaccharide that circulates in the blood.

Why it is important to keep blood glucose levels in the normal range?

Glucose is an important fuel for body cells.

Three most common Monosaccharides:

Glucose, Fructose (fruits and vegetables) and Galactose (part of milk sugar).

Ketosis

High levels of ketones in the blood.

Why are carbohydrates that cannot be digested important for health?

Indigestible carbohydrates are a food source for the bacteria in the colon.

Where on a food label can you find information about added sugars?

Ingredients List.

Which type of fiber is plentiful in beans?

Insoluble Fiber

How do insulin and glucagon affect blood glucose levels?

Insulin: allows to glucose to enter cells and stimulate the synthesis of protein, fat, and liver and muscle glycogen. Glucagon: Raises level by signaling liver cells to break down glycogen into glucose, which is released into the blood.

Germ

Located at the base of the kernel, is the embryo where spouting occurs.

Three most common Disaccharides:

Maltose, Sucrose, Lactose.

Anaerobic Metabolism

Metabolism in the absence of oxygen.

Aerobic Metabolism

Metabolism in the presence of oxygen. It can completely break down glucose to yield carbon dioxide, water, and enery in the form of ATP.

Simple Carbohydrates

Monosaccharides and Disaccharides have this classification.

How does the U.S. diet compare with recommendations for fiber and added sugar?

Most comes from refined sources, making the diet lower in fiber and high in added sugar than recommended.

Endosperm

Most of the kernel is endosperm. Made up up primarily starch, but is also contains most of the kernel's protein, along with some vitamins and minerals.

Reactive Hypoglycemia

Occurs in response to the consumption of high-carbohydrate foods.

Fasting hypoglycemia

Occurs when an individual has not eaten.

Bran

Outermost bran layers contain most of the fiber and are a good source of many vitamins and minerals.

Complex Carbohydrates

Polysaccharides; they are generally not sweet-tasting the way simple carbohydrates are.

Why is carbohydrate said to spare protein?

Protein not stored in body, which takes away functioning body proteins. So sufficient dietary carbohydrate ensures that protein is not utilized in this way.

Nonnutritive sweetener/artificial sweetener

Provide no calories.

Glycemic Index

Ranking of how a food affects blood glucose relative to the effect of an equivalent amount of carbohydrate from a reference food, such as white break or pure glucose.

Refined

Refers to foods that have undergone processing to remove the coarse parts of the original food.

Oligosaccharides

Short carbohydrate chains containing 3 to 10 sugar units.

Resistance Starch

Starch that escapes digestion in the small intestine of healthy people.

How do the bonds that link the sugar units in starch differ from the bonds that link the units in fiber?

Starch: straight or branched chains of glucose. Fiber: straight or branched chains of monosaccharides, but bonds that link the sugar units cannot be broken by human digestive enzymes.

What is glycogen?

Storage form of glucose in humans and other animals.

Fortification

The addition of nutrients to food.

Enrichment

The addition of specific amounts of thiamin, riboflavin, niacin, and iron to refined grains.

Type 1 Diabetes

The form of diabetes caused by auto-immune destruction of insulin-producing cells in the pancreas, usually leading to absolute deficiency.

Type 2 Diabetes

The form of diabetes characterized by insulin resistance and relative (rather than absolute) insulin deficiency.

Lactose Intolerance

The inability to digest lactose due to a reduction in the levels of the enzyme lactase.

Why does frequent carbohydrate snacking promote dental caries?

The longer teeth are exposed to carbohyrates, the greater the risk of caries.

Glycemic Response

The rate, magnitude, and duration of the rise in blood glucose that occurs after food is consumed.

Glycogen

The storage form of carbohydrate in animals, made up of many glucose molecules linked together in a highly branched structure.

Hemorrhoids

The swelling of veins in the rectal or anal area.

What foods are good sources of calcium for someone with lactose intolerance?

Tofu and fish consumed with bones to supply calcium.

Fiber

Type of complex carbohydrate that cannot be digested by human digestive enzymes; cannot be stored in small intestine and passes into large intestine.

Glycemic Load

Used to rank the effect of a food on blood sugar; considers the glycemic response of a typical portion of food.

Photosynthesis

Uses energy from the sun to covert carbon dioxide and water to glucose.

Insulin Resistance

When body does not produce enough insulin or when body cells loses their sensitivity to it.

Why are foods high in added refined sugars said to contribute to empty calories?

When separated from their plant sources, refined sugars no longer come with the fiber, vitamins, minerals, andothe substances found in the original plant.

Whole-Grain Product

When we eat a bowl of oatmeal or a slice of whole-wheat toast, we are consuming a whole grain product. Whole-grain products include the entire kernel of the grain.

What types of carbohydrate are recommended by MyPyramid?

Whole grains, legumes, and fresh fruits and vegetables, which are low in added sugar and often good sources of fiber.

What is the difference between a whole-grain product and a product made with a refined grain?

Whole-grain products include the entire kernel of the grain; the germ, the bran, and the endosperm. Refined grain products, such as white bread, include just the endosperm. The bran and germ are discarded during refinining, and along with them the fiber and some vitamins and minerals are lost.