Carbohydrates

what is the primary role of carbohydrates?

provide the body with energy

which macronutrient is the preferred source of energy for brain and central nervous system​?

carbs

which parts of the body are sensitive to high blood glucose levels?

Brain and CNS

what happens to people who eat TOO little carbs?

their mental health decreases

what are carbs?

compounds made of single or multiple sugars

what are carbs composed of?

C,H,O

what are the 2 categories of carbs?

simple and complex

where are simple carbs found?

naturally occurring sugars in fruit, milk + added sugars: honey, corn syrup, table sugar​

where are complex carbs found?

starch and fiber

carb monomer?

monosaccharides

what are the 3 monosaccharides?

glucose, fructose, galactose

where is glucose found?

fruits and sweeteners

where is fructose found?

fruits, honey, high fructose corn syrup

where is galactose found?

parts of lactose, found in milk

what is the building block of carbs?

glucose

what is glucose used for?

Used in plant and animal tissues for quick energy​

true/false:

All CHO (except fiber) can be converted to glucose​

true

true/false:

glucose is very sweet

false; glucose is not very sweet

what is the sweetest of the simple sugars?

fructose

what is unique about galactose?

Seldom occurs freely in nature​

true/false:

galactose is part of lactose (milk sugar)

true

what is the name for 2 monosaccharides joined together?

disaccharide

what are the 3 disaccharides?

sucrose, maltose, lactose

sucrose

glucose + fructose​

Table sugar - “sugar”​

maltose

glucose + glucose​

From digestion of starch​

Found in malt beverages/beer​

lactose

glucose + galactose​

Milk sugar​

Aids calcium absorption​

true/false:

All starchy foods are plant foods!​

true

true/false:

Most societies have a primary or staple grain

true

is starch a monosaccharides, disaccharides, or polysaccharide?

polysaccharide

how many glucose units are found in each molecule of starch?

Up to 3,000 glucose units in each molecule of starch!​

what are 2 examples of rich starch sources?

grains and legumes

Legumes

plants of bean & pea family; rich in protein compared to other plant-derived foods​

Legumes are 40% starch by weight​

whole grains are composed of 4 parts but do we eat all of them? if not, which part is excluded

husk

Kernel

part of the wheat plant that is made into flour

what are the 4 parts of a wheat kernel?

Germ, Endosperm, Bran, Husk

Germ

nutrient-rich part of whole grain (grows into plant)​

Endosperm

soft inside portion that contains starch and protein; provides energy​

Bran

fibrous protective coating around the kernel​

Husk

outer, inedible covering of a grain (removed in “whole grain” products)​

Refined

process by which coarse parts of food products are removed

Enriched

B vitamins (thiamin, riboflavin, niacin, folic acid) and iron are added to refined grains and grain products

What was the Enrichment Act of 1942?

any processed flour in the U.S has to be enriched

Fortified foods

nutrients added to prevent deficiency or reduce risk of chronic disease​

can our GI tract digest fiber?

no

why are high fiber foods good for weight loss?

same food but less calories

fiber

Indigestible residues of food, composed of polysaccharides​

why don’t carbs provides energy?

Bonds cannot be broken by human digestive enzymes

what are the 2 forms of fiber?

soluble and insoluble fiber

INSOLUBLE fiber characteristics

• Does not dissolve in water​

• Holds water in colon​

• Increase bulk​

• Stimulates muscles of GI tract​

• Cellulose, hemicellulose, and lignin​

  • Removes waste

SOLUBLE fiber

• Dissolve or swell in water​

• Cholesterol lowering​

• Improved blood glucose control​

• Pectins and gums​

  • Binds to things

which types of carbs are the most valuable for energy nutrients

complex CHO

what portion of grains servings (per day) should be whole grain?

At least half of the recommended grain servings should be whole grains

Are majority of Americans over or under the target amount for fiber?

under

what are major sources of added sugar?

regular soft drinks, sugars and candy, cakes, cookies, pies, fruit drinks, dairy products (ex. Ice cream), sweetened grains (ex. waffles)​

what is the DI for carbs?

45-60% of total calories

what group of people have the highest sugar intake and where does it come from?

males in their teens/early 20’s who drink energy drinks

Digestive system

the body system composed of organs and glands associated with the ingestion and processing of food for absorption of nutrients into the body

Digestion

process by which foods are broken down into smaller absorbable products.

Absorption

passage of nutrients of substances into cells or tissues

how long does it take the body to digest and absorb starch?

1-4 hrs

which enzyme starts the digestion process and breaks starch down into smaller pieces?

amylase

where does carb digestion begin?

in the mouth

CHO metabolism flow through the body?

1) mouth

2) pancreas

3) small intestine

4) liver

5) large intestine

CHO digestion in the mouth

salivary glands secrete a watery fluid to moisten the food and amylase begins to break the starch down into smaller pieces until it is swallowed

pancreas role in CHO metabolism

pancreas releases a carb digesting enzyme and releases them into the small bile duct into the small intestine. These enzymes split polysaccharides into disaccharides. The enzymes of the surface of the small intestine break these into monosaccharides.

where does absorption of monosaccharides occur?

takes place in the small intestine; carbs stop digesting in the small intestine and only starch moves on

liver role in CHO metabolism

simple sugars are absorbed into the blood and travel to the liver where the liver regulates the amount of glucose circulating in the blood in response to the hormones insulin and glucagon

what does the liver convert monosaccharides into?

glucose

large intestine role in CHO metabolism

most fiber passes through the large intestine and excreted with feces

If there is more glucose in the blood than the cells need, the liver and muscles can make and store ___

glycogen

Glycogen

polysaccharaides made of chains of glucose

how long does it take the body to get glucose levels down after a meal?

1-2 hrs

how much of glycogen stores is stored in the muscles and whais it used for?

2/3; used during exercise

how much of glycogen stores is stored in the liver and what is it used for?

1/3; maintains blood

what is different about the way glycogen is distributed/stored in the muscles vs the liver?

muscles keep their own glycogen whereas the liver readily distributes/shares its glycogen stores

Once body’s energy needs are met and glycogen stores are full, CHO are converted to _____!

fat

true/false:

there is unlimited fat storage in the body

true

High blood glucose

extra glucose converts to glycogen or body fat​

Low blood glucose

glucose released from glycogen stores​

Insulin

hormone released from the pancreas in response to high glucose levels; assists in removing glucose from blood

Glucagon

hormone released from the pancreas that signals the liver to release glucose into the blood

What is hyperglycemia?

abnormally high blood glucose concentration

Symptoms of hyperglycemia

increased thirst and urination, fatigue, blurry vision, irritability, depression, hunger

Types of diabetes

Prediabetes, Type 1, Type 2, Gestational

How many Americans have prediabetes?

>54 million

Prediabetes characteristics

●BG levels higher than normal, but not in diabetes range

●Long term damage likely occurring!

●Most people develop Type 2 Diabetes within 10 years

●Can prevent progression to Type 2 Diabetes with diet, exercise, & weight loss (5-10%)

Excess weight = ?

Insulin resistance

What are some risk factors for prediabetes?

Family history of diabetes

•Over age 45

•Overweight

•Inactive

•High Blood Pressure

•Abnormal cholesterol/ triglycerides

•History of diabetes during pregnancy

•Prediabetes

•African American, American Indian, Hispanic, Asian,

What is the best dietary pattern for people with diabetes?

Focus on low fat, balanced meals

●For weight loss and to decrease insulin resistance

●Small meals and snacks best

How many people worldwide have diabetes?

415 million people worldwide have diabetes

What does diabetes rank as in terms of leading causes of death?

Ranks as the 4th or 5th leading cause of death in most developed countries

●Becoming epidemic in many developing and newly industrialized nations

●Certain to be one of the most challenging health problems in the 21st century

When was the first artificial sweetener discovered?

1879

What are the 5 approved artificial sweeteners in the U.S?

Acesulfame-K

●Aspartame

●Neotame

●Saccharin

●Sucralose

Why is stevia not considered one of the 5 approved artificial sweeteners in the U.S?

herbal sweetener; not approved as food additive

Which 2 amino acids is asparatame composed of?

Composed of 2 amino acids: phenylanlanine and aspartic acid (found in everyday foods)

Which types of people should avoid ingesting asparatame?

People with o PKU

What is the FDA acceptable daily intake of asparatame?

FDA Acceptable Daily Intake = 50 mg/kg of body weight

What is the oldest artificial sweetener?

Saccharin