nutrition terms i dont know

Carbohydrates

One of the three energy-yielding macronutrients; made primarily of carbon, hydrogen, and oxygen and provide 4 kcal/g.

Monosaccharides

Single sugar molecules; the simplest form of carbohydrate and the form that can be absorbed by the small intestine.

Three monosaccharides

Glucose, fructose, and galactose.

Glucose

A monosaccharide that is the body's primary blood sugar and an important energy source, especially for the brain.

Fructose

A monosaccharide found naturally in fruits, some vegetables, and honey; also called fruit sugar.

Galactose

A monosaccharide that is primarily obtained from the digestion of lactose.

Disaccharides

Carbohydrates made of two monosaccharides bonded together; include sucrose, lactose, and maltose.

Sucrose

Glucose + fructose; commonly called table sugar.

Maltose

Glucose + glucose; commonly called malt sugar and produced during starch digestion.

Lactose

Glucose + galactose; commonly called milk sugar and found naturally in milk and dairy products.

Sucrose vs. maltose

Sucrose contains glucose + fructose, while maltose contains glucose + glucose.

Polysaccharides

Long chains of glucose molecules; examples include starch, glycogen, and fiber.

Starch

The storage form of glucose in plants and a digestible polysaccharide.

Amylose

A type of starch made of long, mostly straight chains of glucose that humans can digest.

Fiber

Nondigestible carbohydrate found primarily in plants; human digestive enzymes cannot completely break it down.

Amylose vs. fiber

Both are polysaccharides, but amylose is a digestible form of starch while fiber cannot be digested by human digestive enzymes.

Glycogen

The storage form of glucose in humans and animals.

Food sources of starch

Grains, bread, pasta, rice, cereals, potatoes, corn, peas, and legumes.

Food sources of fiber

Whole grains, fruits, vegetables, legumes, nuts, and seeds.

Food sources of sucrose

Table sugar, sweets, desserts, candy, and many foods with added sugar; sucrose also occurs naturally in some fruits and vegetables.

Food sources of maltose

Malted foods and beverages; maltose is also produced when starch is broken down during digestion.

Food sources of lactose

Milk and dairy products.

Where carbohydrate digestion begins

The mouth.

Carbohydrate digestion in the mouth

Salivary amylase begins breaking starch into smaller carbohydrate molecules.

Salivary amylase

Enzyme in saliva that begins starch digestion in the mouth.

Carbohydrate digestion in the stomach

Very little carbohydrate digestion occurs because stomach acid inactivates salivary amylase.

Carbohydrate digestion in the small intestine

Most carbohydrate digestion occurs here with the help of pancreatic amylase and enzymes on the intestinal brush border.

Pancreatic amylase

Enzyme released by the pancreas into the small intestine that breaks starch into smaller carbohydrates.

Maltase

Brush-border enzyme that breaks maltose into two glucose molecules.

Sucrase

Brush-border enzyme that breaks sucrose into glucose and fructose.

Lactase

Brush-border enzyme that breaks lactose into glucose and galactose.

Final products of carbohydrate digestion

Glucose, fructose, and galactose.

Carbohydrates that can be absorbed

Only monosaccharides—glucose, fructose, and galactose.

How far carbohydrates must be digested before absorption

They must be broken down into individual monosaccharides before they can be absorbed into intestinal cells.

Where carbohydrate absorption occurs

Primarily in the small intestine.

Carbohydrate transport after absorption

Monosaccharides enter the blood and travel through the hepatic portal vein to the liver.

Hepatic portal vein

Blood vessel that carries absorbed nutrients from the digestive tract to the liver.

First organ carbohydrates reach after intestinal absorption

The liver.

What happens to fructose and galactose in the liver

They can be converted into glucose or other compounds for use by the body.

Three options for glucose use

Used immediately for energy, stored as glycogen, or converted to fat when energy and glycogen needs are met.

Immediate use of glucose

Cells can break down glucose to produce ATP for energy.

Storage form of glucose in the human body

Glycogen.

Where glycogen is stored

Mainly in the liver and skeletal muscles.

Purpose of liver glycogen

Helps maintain normal blood glucose levels between meals.

Purpose of muscle glycogen

Provides glucose for energy within the muscle during physical activity.

Minimum carbohydrate DRI for adults

130 grams per day.

Why the carbohydrate DRI is 130 g/day

It is based largely on the average amount of glucose needed to supply the brain with adequate glucose.

AMDR for carbohydrates

45–65% of total daily calories.

Fiber recommendation for women ages 19–50

25 grams per day.

Fiber recommendation for men ages 19–50

38 grams per day.

Whole grains

Grains containing all three original parts of the grain kernel—the bran, germ, and endosperm.

Refined grains

Grains that have had the bran and germ removed, leaving primarily the endosperm and removing some fiber, vitamins, minerals, and phytochemicals.

Enriched grains

Refined grains that have certain nutrients added back after processing, usually some B vitamins and iron; fiber is generally not added back.

Whole grain vs. refined grain

Whole grains retain the bran, germ, and endosperm, while refined grains have the bran and germ removed.

Refined vs. enriched grains

Refined grains have nutrients removed during processing; enriched grains are refined grains with certain nutrients added back.

Natural sugars

Sugars naturally present in intact foods, such as fructose in fruit and lactose in milk.

Added sugars

Sugars, syrups, and other caloric sweeteners added to foods or beverages during processing or preparation.

Examples of natural sugars

Fructose in fruit and lactose in milk.

Examples of added sugars

Table sugar added to foods, high-fructose corn syrup in soft drinks, honey or syrups added during preparation, and sugars added to desserts and candy.

Recommendation for added sugar

Keep added sugars below 10% of total daily calories.

Sugar substitutes

Sweeteners used instead of sugar; many provide little or no energy and are much sweeter than regular sugar.

Characteristics of sugar substitutes

Usually very sweet, used in small amounts, and often contribute few or no calories.

Benefits of sugar substitutes

Can reduce added sugar and calorie intake, may help with blood glucose management, and generally do not promote tooth decay like sugar does.

Lactose intolerance

Reduced ability to digest lactose because the small intestine produces insufficient lactase.

Cause of lactose intolerance

Low production of the enzyme lactase.

Symptoms of lactose intolerance

Gas, bloating, abdominal discomfort, and diarrhea after consuming more lactose than the person can tolerate.

Recommendations for lactose intolerance

Consume smaller amounts of dairy at a time, eat dairy with meals, try yogurt or hard cheeses, choose lactose-free or lactose-reduced milk, or use lactase enzyme products.

Why some people with lactose intolerance can still eat dairy

Lactose intolerance varies in severity, and many people can tolerate small amounts of lactose or lower-lactose dairy products.

Two types of dietary fiber

Soluble fiber and insoluble fiber.

Soluble fiber

Fiber that dissolves or forms a gel in water and is often fermented by intestinal bacteria.

Good sources of soluble fiber

Oats, barley, legumes, apples, citrus fruits, and some other fruits and vegetables.

Benefits of soluble fiber

Can help lower blood cholesterol, slow glucose absorption, improve blood glucose control, and support healthy gut bacteria.

Insoluble fiber

Fiber that does not dissolve in water and adds bulk to stool.

Good sources of insoluble fiber

Wheat bran, whole grains, vegetables, and the skins of many fruits and vegetables.

Benefits of insoluble fiber

Promotes regular bowel movements, adds bulk to stool, and helps prevent constipation.

Type 1 diabetes

An autoimmune disease in which pancreatic beta cells are destroyed, resulting in little or no insulin production.

Type 2 diabetes

A condition characterized primarily by insulin resistance, often combined over time with reduced insulin production.

Most common type of diabetes

Type 2 diabetes.

Major treatment for Type 1 diabetes

Insulin therapy is essential because the body produces little or no insulin.

Major treatment approach for Type 2 diabetes

Lifestyle management, especially healthy eating, physical activity, and weight management when appropriate; medications and/or insulin may also be needed.

Insulin

Hormone produced by pancreatic beta cells that lowers blood glucose by promoting glucose uptake and storage.

When insulin is released

When blood glucose rises, especially after eating a carbohydrate-containing meal.

Main action of insulin

Lowers blood glucose by helping cells take up glucose and promoting storage of glucose as glycogen.

Glucagon

Hormone produced by pancreatic alpha cells that raises blood glucose.

When glucagon is released

When blood glucose becomes low, such as between meals or during fasting.

Main action of glucagon

Raises blood glucose by stimulating the liver to break down glycogen and produce/release glucose.

Epinephrine

Hormone produced by the adrenal glands that helps raise blood glucose during stress or increased energy demand.

When epinephrine is released

During stress, exercise, or a fight-or-flight response.

Main action of epinephrine on blood glucose

Promotes glycogen breakdown and helps make glucose rapidly available for energy.

Three hormones involved in blood glucose regulation

Insulin, glucagon, and epinephrine.

Insulin source

Beta cells of the pancreas.

Glucagon source

Alpha cells of the pancreas.

Epinephrine source

Adrenal glands.

Hormone that lowers blood glucose

Insulin.

Hormones that can raise blood glucose

Glucagon and epinephrine.

Diverticulosis

A condition in which small pouches called diverticula form in weak areas of the wall of the colon.

Diverticulitis

Inflammation and/or infection of one or more diverticula.

Diverticulosis vs. diverticulitis

Diverticulosis means diverticula are present; diverticulitis occurs when diverticula become inflamed.

Recommendation to reduce risk of diverticular disease

Consume an adequate high-fiber diet along with adequate fluids and regular physical activity.

Main function of carbohydrates

Provide energy for the body, particularly glucose for the brain and working muscles.