IPHY 2420: Intro to Nutrition EXAM 1

Which disease or condition is a risk factor for many chronic diseases and conditions?

Obesity

What is the measure of energy in foods?

kilocalories (kcal)

List the macronutrients

Carbohydrates

Fat

Protein

List the major features of the macronutrient: Carbohydrates

Carbon, Hydrogen, Oxygen

4 calories/gram

primary energy source

List the major features of the macronutrient: Fat

Carbon, Hydrogen, Oxygen

9 calories/gram

primary energy source

List the major features of the macronutrient: Protein

Carbon, Hydrogen, Oxygen, Nitrogen

4 calories/gram

last resort energy source

List the micronutrients

Vitamins-Fat Soluble

Vitamins-Water Soluble

Minerals-Major

Minerals-Trace

List the major features of the micronutrient: Fat Soluble Vitamins

A, D, E, K

stored in the body

toxicity is possible

List the major features of the micronutrient: Water Soluble Vitamins

B, C

not stored in the body

excess excreted in urine-toxicity unlikely

List the major features of the micronutrient: Major Minerals

calcium, sodium

>100mg required daily

List the major features of the micronutrient: Trace Minerals

iron, zinc

<100mg required daily

How many calories per gram do carbohydrates provide?

4 calories/gram

How many calories per gram do fats provide?

9 calories/gram

How many calories per gram do protein provide?

4 calories/gram

List the fat soluble vitamins.

A, D, E, K

List the water soluble vitamins.

B, C

What is a DRI?

Dietary Reference Intake

What is a RDA?

Recommended Dietary Allowance

What is a AI?

Adequate Intake

What is a UL?

Tolerable Upper Intake Level

What factors go into calculating an individual's estimated energy

requirement?

Age

Weight

Height

Gender

Activity

What is the AMDR?

AMDR: Acceptable Macronutrient Distribution Range is the range of intake associated with reduced chronic disease risk and is expressed as % of calories

What is the AMDR for the macronutrient: Carbohydrate

45-65%

What is the AMDR for the macronutrient: Fat

20-35%

What is the AMDR for the macronutrient: Protein

10-35%

Be able to identify reputable sources of nutrition information (e.g. Registered Dietitian).

Trustworthy Experts: Registered Dietitian Nutritionist (RDN) and Dietetic Technician, Registered (DTR)

Professionals With Advanced Degree(s) In Nutrition: B.A./B.S, M.S., and Ph.D.

Medical Doctor With Appropriate Expertise In Nutrition: M.D. and D.O.

Naturopath (N.D.)

Identify and explain the four characteristics of a healthy diet.

Discuss the features of an ingredient list on a food label.

1. Serving size and servings per container

2. Calories and calories from fat per serving

3. List of nutrients

4. % Daily Values

5. Footnote for Daily Values

Understand why the inclusion of a serving size designation on a nutrition facts label is important.

Serving sizes can be used to plan appropriate amounts of food and standardized serving sizes allow for comparisons among similar products

What is being added to the new (required by 2020) nutrition facts label on foods?

Vitamin D and Potassium were added because many Americans don't get enough of these. Grams of Added Sugars were also added underneath Total Sugars. Font size of serving size and calories got bigger.

What are new food serving sizes aiming to be based on? What have previous food serving sizes been based on?

Serving sizes are based on what people typically consume, not what they should consume, which is what food serving sized were originally based on.

What nutrition information are eating establishments (with 20+ locations) required to post on menus and menu boards?

Beginning May 7, 2018, the FDA requires that calories be listed next to the name or price of a food on menus and menu boards that are part of a chain of 20+ locations.

What is the definition of a nutrient dense food?

Foods that provide the most nutrients for the fewest calories

Be able to identify nutrient dense foods.

Vegetables

What are empty calories?

Calories from solid fats and/or added sugars that provide few or no nutrients

Be able to identify a food with empty calories.

Candy

Explain the concept of energy balance and its effects on body weight?

Energy balance is energy intake versus energy expenditure (what you are burning or calories in versus calories out); macronutrient composition of the diet

When the calories you consume meet your needs, you are in energy balance and your weight will be stable (energy intake=energy expenditure=weight maintenance)

When you consume fewer calories than you expend, your body will draw upon your stored energy to meet its needs and you will lose weight (energy intakeenergy expenditure=weight gain)

What are the goals of digestion?

Break large molecules down to smaller molecules

Absorb the smaller molecules into the cells of the body

What is a cell membrane made up of?

Selectively permeable outer layer enclosing each cell of the body

Made up of a phospholipid bilayar with a hydrophobic interior and hydrophilic exterior; the bilayer contains phospholipids with a hydrophobic tail and hydrophilic head; also contains proteins embedded in the bilayer that move nutrients in and out of the cell

What area of the brain is involved in the regulation of feeding?

The hypothalamus region of the brain

Amount and type of food consumed have an influence over it; nerve receptors in the stomach and small intestine send messages to hypothalamus; solid foods are more filling than semisolid foods or liquids

Explain how nerve receptors in the stomach regulate hunger.

Nerve receptors in the stomach and small intestine send messages to hypothalamus

What are hormones?

Chemicals produced in glands that travel in the blood to target organs in other parts of the body

Can stimulate hunger or produce a feeling a satiety

They relay messages to the hypothalamus

How do the different macronutrients affect our satiety level?

Feeling of fullness

The macronutrient that will make you feel the most full is protein, followed by fat, and carbohydrates.

Be familiar with the layout of the gastrointestinal system (i.e., order of the different parts of it).

GI Tract: Series of organs arranged as a long tube through which the food passes

1. Digestion begins in the mouth

2. The esophagus propels food from the mouth into the stomach

3. The gastroesophageal sphincter separates the esophagus from the stomach which prevents the flow of food from the stomach back into the esophagus

4. From the stomach, chyme is slowly released through the pyloric sphincter to the small intestine (chemical digestion continues in the small intestine using pancreatic enzymes and bile, and there is no more mechanical digestion at this point)

5. Water-soluble nutrients will enter the portal vein; carbohydrate, protein, minerals, some vitamins (all B vitamins and vitamin C); portal vein transports these nutrients to the liver; Fat-soluble nutrients will enter the lymphatic vessels; fat and some vitamins (vitamins A, D, E, K); lymphatic vessels transport these

nutrients directly to the bloodstream and then to the liver

6. Undigested food components move through a sphincter called the ileocecal valve to the large intestine

7. In the large intestine, very little digestion takes place; intestinal bacteria digest remaining food particles; water and some nutrients are absorbed; material is stored 12-~24 hours prior to elimination

What are sphincters?

muscles that control the passage of material from one organ to the next

What is mechanical digestion?

chewing or the mixing of food with gastric juice

What is chemical digestion?

enzymes are used for breaking down food chemically (ex. salivary amylase is an enzyme produced by the salivary glands that begins the chemical digestion of carbohydrates)

What type(s) of digestion occur in the mouth?

mechanical (chewing) and chemical (salivary amylase is an enzyme produced by the salivary glands that begins the chemical digestion of carbohydrates)

What type(s) of digestion occur in the stomach?

mechanical (food being mixed with gastric juice) and chemical (digestion of proteins and fats)

What type(s) of digestion occurs in the small intestine?

no more mechanical digestion at this point and chemical (digestion continues in the small intestine using pancreatic enzymes and bile)

What does the suffix-'ase' indicate?

An enzyme

What is peristalsis?

The muscular contractions moving food through the GI tract

What is chyme?

Semisolid product of digestion in the stomach

What is gastric juice made up of?

Hydrochloric acid (HCl) (protein)

Pepsin (enzyme, protein)

Gastric lipase (fat)

Intrinsic factor (vitamin B12)

List the accessory organs that are involved in digestion.

Salivary glands

Liver

Gallbladder

Pancreas

What does the accessory organ, the salivary glands, do in the process of digestion?

produce the enzymes that break down food chemically

What does the accessory organ, the liver, do in the process of digestion?

produces bile

What does the accessory organ, the gallbladder, do in the process of digestion?

stores bile

What does the accessory organ, the pancreas, do in the process of digestion?

produces many digestive enzymes and produces bicarbonate to neutralize chyme

What is absorption and where does it occur?

Process of taking molecules across a cell membrane (stomach, intestine) and into the body

A small amount of the process occurs in the stomach and large intestine

Most of the process occurs in the small intestine

What are villi and what function do they serve?

finger-like projections on the folds and contain capillaries to absorb nutrients

What are microvilli and what function do they serve?

make up the brush border that further increase the surface area to facilitate greater absorption

How are water soluble nutrients absorbed?

enter the portal vein

include carbohydrate, protein, minerals, some vitamins (all B vitamins and vitamin C)

portal vein transports these nutrients to the liver

How are fat soluble nutrients absorbed?

enter the lymphatic vessels

include fat and some vitamins (vitamins A, D, E, K)

lymphatic vessels transport these nutrients directly to the bloodstream and then to the liver

What happens in the large intestine in terms of digestion and absorption?

Very little digestion takes place

Intestinal bacteria digest remaining food particles

Water and some nutrients are absorbed

Material is stored 12-~24 hours prior to elimination

What is heartburn?

A back-flow of gastric juice into the esophagus that causes a burning sensation

What is GERD (Gastroesophageal Reflux Disease) and what are the risk factors for it?

Chronic disease; painful, persistent heartburn is the most common symptom

Risk factors: smoking, alcohol use, overweight, pregnancy, trigger foods, large meals (creates pressure in the stomach), lying down after eating

What are peptic ulcers and what causes them?

Regions of the GI tract that have been eroded by HCl and pepsin

Stress, spicy food, alcohol no longer considered a major contributor to peptic ulcers (they causes may be involved, but they're not the main cause)

The bacterium Helicobacter pylori contributes to most gastric and duodenal ulcers; H. pylori thrives in an acidic environment and breaks down GI lining

List the recommendations given for preventing and treating peptic ulcers.

Treat with antibiotics and acid suppressants

Prevent w/hand washing, proper handling of food

What contributes to the development of peptic ulcers?

The bacterium Helicobacter pylori contributes to most gastric and duodenal ulcers

H. pylori thrives in an acidic environment and breaks down GI lining

List the potential causes of diarrhea.

Food intolerances

Infection of the GI tract

Stress

Bowel (intestines) disorders

What is the concern associated with diarrhea?

Can lead to severe dehydration

Which populations is diarrhea more of a concern for?

It is more dangerous for children and the elderly

Many children die every year from it

What is a food intolerance?

a particular food causes numerous unpleasant symptoms, including gas, pain, and diarrhea; may involve the immune system, but not anaphylaxis

What is a food allergy?

hypersensitivity reaction of the immune system to a component in a food; can be life-threatening; may need epinephrine (epi-pen)

List the monosaccharides.

Glucose

Fructose

Galactose

Describe disaccharides.

Consist of two monosaccharide molecules; one is always glucose (Sucrose, Maltose, Lactose)

Which monosaccharides make up maltose?

Glucose + Glucose

Which monosaccharides make up sucrose?

Glucose + Fructose

Which monosaccharides make up lactose?

Glucose + Galactose

Describe glucose.

The most abundant carbohydrate in the diet

Principal form of carbohydrate found in blood "Blood sugar"

Produced by plants through photosynthesis

Found in plants as a component of disaccharides and

complex carbohydrates

The preferred source of energy for the brain

An important source of energy for all cells

Describe fructose.

Sweetest natural sugar

Found in fruit & high-fructose corn syrup

Where in the diet is each disaccharide (maltose, sucrose, and lactose) typically found?

Maltose is found in starchy grains, vegetables and fruits.

Sucrose is found in fruits and vegetables and is purified from sugar cane and sugar beets

Lactose is found in milk and dairy products such as cow's milk, goat's milk, yogurt, cheese and ice cream.

What is the most common carbohydrate in the diet?

Glucose

Which monosaccharide is measured in the blood as a measure of "blood sugar?"

Glucose

Which monosaccharide is found in fruit?

Fructose

What are complex carbohydrates (polysaccharides)? What are the 3 types?

Poly = many and Saccharide = sugar

Chains of monosaccharides linked together

Starch, Glycogen, Fiber

What is starch? What are common food sources of starch?

Plants store glucose as polysaccharides in the form of starch

Our cells cannot use complex starch molecules as they exist in plants; we must digest (break down) starch to glucose

Grains, legumes, and tubers are good sources of dietary starch

What is glycogen?

Animals (including humans) store glucose as

a polysaccharide in the form of glycogen

Stored in the liver and muscles

Not found in food and therefore not a source

of dietary carbohydrate

Where is glycogen stored in the body?

liver and muscles

Describe fiber.

support structure of leaves, stems, plants

What is dietary fiber?

the non-digestible part of plants; fiber found naturally in foods

What is functional fiber?

fiber extracted from plants and added to foods and supplements; cellulose, guar gum, pectin, psyllium

What is Total Fiber Intake?

dietary + functional fiber

What are the properties, sources, and benefits of soluble fiber?

Properties: dissolves in water, viscous, easily digested (fermented) by bacteria in the colon

Sources: citrus fruits, berries, oats, and beans; used to thicken and stabilize foods (ex. Jams and jellies)

Benefits: lowers risk for cardiovascular disease and type 2 diabetes; lowers blood cholesterol and manages blood glucose levels

What are the properties, sources, and benefits of insoluble fiber?

Properties: generally does not dissolve in water; not fermented by bacteria in the colon

Sources: whole grains (e.g., wheat, rye, brown rice); many vegetables

Benefits: promote regular bowel movements; alleviate constipation; reduce the risk for diverticulosis

What is diverticulosis and how is it treated?

A condition in which small, bulging pouches develop in the digestive tract and can cause symptoms like belly pain or cramping, bloating, constipation, and diarrhea

Treatment: high-fiber diet or fiber supplements ; probiotics

What is diverticulitits and how is it treated?

An inflammation or infection in one or more small pouches in the digestive tract which can cause severe abdominal pain, fever, nausea and a marked change in your bowel habits

Treatment: liquid or low-fiber diet; antibiotics, penicillin, dietary supplement

Explain how a high-fiber intake is related to blood cholesterol levels.

1. Liver synthesizes bile using cholesterol

2. Bile is stored in gallbladder

3. Bile is secreted into intestine to aid in the digestion of fat

(a) High-fiber diet

4a. Fiber binds to bile and both are excreted in the feces

5a. Less cholesterol is reabsorbed from the remaining bile

6a. Blood levels of cholesterol are reduced

Explain how a low-fiber intake is related to blood cholesterol levels.

1. Liver synthesizes bile using cholesterol

2. Bile is stored in gallbladder

3. Bile is secreted into intestine to aid in the digestion of fat

(b) Low-fiber diet

4b. Less fiber is present to bind to bile, so less bile is excreted in the feces

5b. More cholesterol is reabsorbed from the remaining bile

6b. Blood levels of cholesterol are elevated