Nutrition 110: Exam 1

What are the six classes of nutritents?

• Carbohydrates

• Fats

• Proteins

• Vitamins

• Minerals

• Water

Essential nutritents

Must be obtained from food; the body cannot make them but they are indispensable.

• Regulate the release of energy and other aspects of metabolism.

• Do not themselves provide energy.

Vitamins and minerals

• The mediums for the body’s processes.

Water

What nutrient provides energy for the brain and nervous system?

Glucose (carbohydrates)

• Are necessary for living tissue to be built.

• Function as enzymes, antibodies, hormones, tendons/ligaments, filaments, etc.

Proteins

• The body’s chief form of energy sources

• Provide satiety

Fats

• A sedative

• Can impair central nervous system functioning

Alcohol

Organic, or carbon-containing, essential nutrients that are vital to life but needed only in relatively minute amounts.

Vitamins

Which vitamins are fat soluble?

Vitamins A, D, E, and K

Inorganic compounds, some of which are essential nutrients. There are both major and trace.

Minerals

Any condition caused by an excess, defiency, or imbalance of calories or nutrients.

Malnutrition

Calorie or nutrients overconsumption severe enough to cause disease or increase risk of disease. A form of malnutrition.

Overnutrition

What are some risk factors that greatly attribute to deaths in the U.S.?

High blood pressure, smoking, high blood sugar, obesity, and a diet low in whole grains.

Chronic disease characterized by deterioration of body organs as a result of misuse and neglect. Some examples include heart disease, cancer, osteoporosis, and diabetes.

Degenerative diseases

A National Agenda for Improving Nutrition and Health – Trying to Make America Healthier. Objectives are set to help maintain good health, prevent disease, and promote healthy behaviors.

Healthy People 2030

Hunger vs. appetite

• Hunger = the physiological need for food

• Appetite = the psychological desire for food which could be stimulated in response to the senses even if you are not hungry

What factors influence our food choices?

• What food is available to us

• Income, prices, and convenience

• Advertising and media

• Social and cultural factors

• Personal values and beliefs

• Other factors, such as tastes

What are some perceived barriers to healthful eating?

• It costs more → not always true, but may be

• Too much conflicting information

• Healthful foods don’t taste as good

• The people I eat with do not eat healthful foods

What are some straregies to help you eat well?

• Buy local and fresh

• Shop the perimeter

• Take a list

• Check sell by and use by dates

How can you determine if information is reliable?

CARS: Credibility, accuracy, reasonableness, support

How many calories are in a gram of each of the macronutrients, and in alcohol?

• Carbohydrates = 4

• Protein = 4

• Fat = 9

• Alcohol = 7

What are the top three causes of deaths in the United States?

Heart disease, cancer, and stroke

Areas where people live to be 100+ years or older.

Blue zones. Strategies that seem to help their health are walking frequently, eating plant-based foods, eating moderately, and moving naturally instead of exercising.

Food desert

A low-income tract where residents do not have access to a supermarket or large grocery store.

What does an ideal dietary pattern give you?

Adequate nutrients, fiber, and calories without excess added sugars, solid fats, and sodium.

What are the ABCs of eating for health?

• Adequacy

• Balance

• Calorie control

• Nutrient density

• Moderation (avoid excess)

• Variety

What are the dietary reference intakes?

A set of reference values for daily standards for energy and nutrients; an estimate of the energy and nutrient needs of healthy people.

The amount that will prevent deficiency symptoms

Nutrient requirement

Estimated average requirement (EAR)

The amount of a nutrient that is estimated to meet the requirement for the nutrient in half of the people for a specific age and gender.

Recommended dietary allowance (RDA)

The average daily amount of a nutrient that meets the nutrient needs of 97 to 98 percent of healthy individuals of a specific age and gender. This is the one that we are probably most concerned with for our own personal nutrition,

Adequate Intake (AI)

The average amount of a nutrient that appears to be adequate for individuals when there is not sufficient evidence/research to calculate the recommended dietary allowance (RDA).

Tolerable upper intake level (UL)

Maximum amount of a nutrient that is unlikely to pose any risk of adverse health effects to most healthy people.

Chronic disease risk reduction intakes (CDRR)

Nutrient intakes associated with a risk of chronic disease.

What percentage of your diet should come from carbohydrates daily?

45-65%

What percentage of your diet should come from fats daily?

20-35%

What percentage of your diet should come from protein daily?

10-35%

American’s diets tend to have too much what and too few?

Calories, solid fats, added sugars, refined grains, and sodium. We tend to have too few vegetables, fruits, whole grains, dairy products, and oils

Health claims

A statement linking the nutritional profile of a food to a reduced risk of a particular disease; these statements are strictly regulated by the FDA.

How does the DRI change over time?

They evolve with new scientific evidence.

Estimated energy requirement (EER)

Estimated amount of energy you need.

Acceptable macronutrient distribution range (AMDR)

Range of intakes for a sources that is associated with a reduced risk of chronic disease while providing adequate intake of essential nutrients.

Essential nutrients

Compounds that must be obtained from food because they
cannot be synthesized by the body in amounts sufficient to meet physiological need.

What happens neurologically when fuel reserves are exhausted?

Nerve cells in the hypothalamus generate nerve impulses to signal hunger, and the cortex experiences hunger and appetite.

What must the digestive system do to utilize the food we eat?

• Passage through the GI tract

• Secretion of digestive juices and enzymes

• Digestion of food

• Absorption of water and nutrients

• Circulation of blood through the body to distribute and absorb substances

• Control of these functions

Where does digestion first begins? What happens?

The mouth

• mechanical digestion

• Salivary amylase begins chemical digestion

• The food bolus is moistened and moves to the esophagus

Choking

A piece of food or small objects get caught in throat and block the airway

Where are salivary amylase and salivary lipase produced?

The salivary glands

After food is done in the mouth, where does it go? What happens?

The esophagus

• Passes the food from the mouth to the stomach

• Upper esophageal sphincter and lower esophageal sphincter

  • Closing of the LES protects the esophagus from stomach acid

• Peristalsis moves food down the stomach

What type of muscles move food along the GI tract?

Longitudinal and circular muscles

Why does acid reflex/heartburn occur?

• Acidic stomach contents back up into the esophagus due to the LES not closing completely, which causes a painful, burning sensation.

• Can lead to GERD if untreated.

• Can be caused by greasy foods, caffeine, large meals, alcohol, cigarettes, lying down after eating, medications

What are the digestive Secretions in the esophagus?

Mucus to protect the lining of the esophagus

After foods moves through the esophagus, where does it go? What happens?

Food goes into the stomach.

• The stomach stores food until it is processed, forms chyme, and releases chyme into the small intestine.

How does the stomach determine how much chyme to empty?

It does it at a rate suitable for proper digestion and absorption. The process is controlled by the pyloric sphincter, the nervous system, and hormonal mechanisms.

How does the stomach contents mix and how does the stomach empty?

What are digestive Secretions in the stomach?

• Gastric juice = mixes with the bolus

• HCl = denatures protiens

• Mucus = coats the stomach as protection

• intrinsic factor = essential for the absorption of B12

• Enzymes = pepsin that helps with protein digestion

Once food goes through the stomach, where does it go? What happens?

The small intestine

• This is the major section/organ of digestion and absorption

• After digestion, most nutrients are absorbed through the specifically configured walls of the small intestine

• Nutrients are delivered to the blood and the lympt

Villi

Fingerlike projections of the sheet of cells that line the GI tract; the villi make the surface area much greater than it would otherwise be.

Lymph

The fluid outside the circulatory system that bathes the cells; derived from the blood by being pressed through the capillary walls; similar to the blood in composition.

Microvilli

Tiny hairlike projections on each cell of the intestinal tract lining that can trap nutrient particles and translocate them into cells.

When chyme arrives in the small intestine, what do the accessory organs do?

• The gallbladder sends a fat emulsifier called bile in an amount matched to the fat present.

• The pancreas releases bicarbonate to neutralize stomach acid.

• Enzymes from the pancreas and small intestines work to breakdown the large nutrients to make smaller and smaller units that can be used by cells.

Bile

A compound made from cholesterol by the liver, stored in the gallbladder, and secreted into the small intestines. It prepares lipids for enzymatic digestions.

How does bile work?

1. Fat and water cannot mix, so enzymes cannot get to the fat.

2. The bile has an affinity for fats and for water so it brings them together.

3. The small droplets of emulsified fats are able to be mixed with enzymes.

What digestive Secretions are in the small intestines?

• mucus

• Enzymes: sucrase, Lactase, maltase

Sucrase splits

sucrose into glucose and fructose

Lactase splits

lactose into glucose and galactose

Maltase splits

maltose into glucose and glucose

Where does food go after it is in the small intestine? What happens?

Food goes into the large intestine.

• All chemical digestion has been completed

• Bacteria break down and digest some fiber and synthizise absorbable vitamin K

• Bacteria absorb minerals and vitamins

How are peristaltic movements different in the large and small intestine?

In the large intestine, movements are much more infrequent and sluggish.

What are the accessory digestive organs?

The liver, the gallbladder, the pancreas

What does the liver do?

It determines the metabolic fate of every nutrient we digest and absorb as well as producing bile. It detoxes, excretes, helps with CHO/fat/protein metabolism, and synthesizes bile salts.

What does the gallbladder do?

It stores and concentrates bile (the sphincter of Oddi controls bile release into the small intestine). When chyme with fatty content enters the SI, cholecystokinin stimulates the gallbladder to contract and the spincter to open.

What does the pancreas do?

It has endocrine and exocrine functions.

Endocrine

A gland secreting a hormone into the blood stream.

Exocrine

A gland that secretes hormones through a duct into a body cavity or into the surface of the skin.

What are the endocrine functions of the pancreas?

• The islets of Langerhands perform these functions and controls blood glucose levels.

What are the exocrine functions of the pancreas?

• Digestive enzymes and bicarbonate; releases pancreatic amylase, pancreatic lipase, trypsin (breaks down protiens), and bicarbonate (neutralizes acid in the stomach)

Where do nutrients for from the digestive system?

Capillaries from the intestine carry nutrients to the veins, and the veins converge into a single large vein that carries nutrients to the liver. The liver cells process these nutrients and produce glucose, lipoproteins, and amino acids.

Where does glucose go?

• It is used immediately by cells

• Stored in muscles as glycogen

• Stored in the liver as glycogen

Where do animo acids go after digestion?

Circulate in the blood until picked up by tissues for building, repairing, and replacing cellular proteins.

Where do fats go after digestion?

• Get stored in fat cells that have unlimited storage capacity

• Glucose and amino acids can be converted into fats and stored in fat cells

What happens to nutrients leaving the digestive system via lymph?

• Nutrients are packaged as chylomicrons

• Cells withdraw fats from the chylomicrons as they circulate throughout the body

Catabolism

The breakdown of body compounds; produces energy

What does glycogen break down into?

Glucose

What do trigycerides break into?

Fatty acids and glycerol

What do proteins break into?

Amino acids

Anabolism

Reverse of catabolism'; glucose, fat, and animo acids are used to build the structures and energy reserves neessary for normal body functions.

Microbiome

The collective genomes of microorganisms in a particular environment.

Gut microbiota

The community of microorganisms themselves.

• Collection varies by individual

• Roles such as fiber breakdown and vitamin K synthesis

Dysbiosis

Imbalance in the gut microbial community. Can cause a increased disease risks.

Living microorganisms (friendly live bacteria and yeasts)
that when consumed in a viable form and in adequate amounts, are
intended to have health benefits for the body, such as helping to
maintain or restore desirable numbers of beneficial bacteria in the
digestive tract. They are usually added to yogurt or taken as food
supplements

Probiotics

Nondigestible carbohydrates, such as fermentable dietary fiber (found in such foods as oatmeal, flax, legumes), that are resistant to digestion in humans, but can be fermented by intestinal bacteria, serve as food for beneficial probiotic bacteria, and favor the growth of beneficial bacteria over harmful bacteria in the digestive tract.

Prebiotics