nutrition midterm

type 1 diabetes

- Age of onset: <30 years - Autoimmune diseases, viral infections, inherited factors - Destruction of pancreatic beta cells; insulin deficiency - Insulin therapy (always)

type 2 diabetes

- Age of onset: >40 years - Obesity, aging, inherited factors - Insulin resistance; insulin deficiency (relative to needs) - Insulin therapy (sometimes)

non-modifiable risk factors for CHD

- Increasing age (potential onset of 45 yrs or older) - Male gender - Family history of premature heart disease

modifiable risk factors for CHD

-High blood LDL cholesterol - Low blood HDL cholesterol - High blood triglyceride (VLDL) levels - High blood pressure (hypertension) - Diabetes - Obesity (especially abdominal obesity) - Physical inactivity - Cigarette smoking - An "atherogenic" diet (high in saturated fats and low in vegetables, fruits, and whole grains)

digestion of carbs in large intestine

1-4 hours later, all sugars/starches have been digested, only fiber remains in digestive tract. Fiber in digestive tract attracts water which softens stool. Some fibers ferment, creates gas and short-chain fatty acids. Colon cells use this for energy.

maltose, sucrose, lactose

3 types of disaccharides

glucose, fructose, galactose

3 types of monosaccharides

hydrolysis

Breaking down disaccharides into 2 by the chemical addition of water

digestion of carbs in the stomach

CARB DIGESTION CEASES HERE. _______ acid and protein digesting enzymes deactivate amylase. _______ juices don't have enzymes to break down carbs. Feeling of satiety (fullness).

Polysaccharides

Carbohydrates that are made up of more than two monosaccharides

negative nitrogen balance

Condition occurring when the body excretes more nitrogen than it takes in

greater than 60

Desirable blood levels for HDL (mg/dL)

less than 100

Desirable blood levels for LDL (mg/dL)

structure of an amino acid

Each contains an amino group, an acid group, a hydrogen atom, and a distinctive side group, all attached to a central carbon atom

role of bacterial enzymes in large intestines

Fibers in the large intestine attract water, which softens the stools for passage without straining. Also, bacteria in the GI tract ferment some fibers. This process generates water, gas, and short-chain fatty acids

absorption of carbs

Glucose and galactose enter cells lining small intestine by active transport. Fructose absorbed by facilitated diffusion. Fructose and galactose metabolized in liver. Glucose sent out to body's cells for energy.

lipid digestion in the stomach

LITTLE FAT DIGESTION HAPPENS HERE. Stomach churns to break up particles-exposes fat for attack by gastric lipase enzyme (works best in stomach acid pH)

lipid digestion in the small intestine

MOST FAT DIGESTION HAPPENS HERE. When fat enters, it triggers release of hormone cholecystokinin (CCK), which signals gall bladder to release stores of bile. Bile originally made in liver from cholesterol. Bile acids of 10 pair up with an amino acid (building block of protein). Bile acts as an emulsifier, drawing fat molecules to surrounding watery fluids. Here, fats are fully digested as they encounter lipase enzymes from pancreas and small intestine. Most bile reabsorbed from ______ ______ and recycled, can also be trapped by fiber and excreted.

digestion of carbs in small intestine

MOST OF CARB DIGESTION HAPPENS HERE. Pancreatic amylase enters intestine via pancreatic duct and breaks down polysaccharides even further to shorter glucose chains and maltose. Final step takes place on outer membranes of intestinal cells.

Monosaccharides

Single sugar molecules

lipid digestion in the mouth

Some hard fats begin to melt at body temperature. Sublingual salivary gland at the base of the tongue secretes lingual lipase. Degree of hydrolysis by lingual lipase is slight for most fats but may be appreciable for milk fats (especially for infants)

role of protein as transporters

Some proteins move about in the body fluids, carrying nutrients and other molecules. The protein hemoglobin carries oxygen from the lungs to the cells. The lipoproteins transport lipids around the body. Special transport proteins carry vitamins and minerals.

Transamination

The process by which an amino group from one amino acid is transferred to a carbon compound to form a new amino acid

protein absorption in small intestine

When polypeptides enter, several pancreatic and intestinal proteases hydrolyze them further into short peptide chains, tripeptides, dipeptides, and amino acids. Then peptidase enzymes on the membrane surfaces of the intestinal cells split most of the dipeptides and tripeptides into single amino acids. Only a few peptides escape digestion and enter the blood intact.

lactose intolerance

a condition that results from the inability to digest the milk sugar lactose; characterized by bloating, gas, abdominal discomfort, and diarrhea. Lactose intolerance differs from milk allergy, which is caused by an immune reaction to the protein in milk

Adequecy

a diet that provides sufficient energy and enough of all the nutrients to meet the needs of healthy people

peptidase

a digestive enzyme that hydrolyzes peptide bonds

whole grain

a grain that maintains the same relative proportions of starchy endosperm, germ, and bran as the original (all but the husk); not refined

Epinephrine

a hormone of the adrenal gland that modulates the stress response; formerly called adrenaline. When administered by injection, epinephrine counteracts anaphylactic shock by opening the airways and maintaining heartbeat and blood pressure

insulin

a hormone secreted by special cells in the pancreas in response to (among other things) elevated blood glucose concentration. Insulin controls the transport of glucose from the bloodstream into the muscle and fat cells

glucagon

a hormone secreted by special cells in the pancreas in response to low blood glucose concentration. Glucagon elicits release of glucose from liver glycogen stores

glycemic index

a method of classifying foods according to their potential for raising blood glucose (soda=high, 65, low=whole wheat)

Dietary Guidelines for Americans

a set of recommendations for healthful eating and active living including fruits and vegetables cover half the plate, grains occupy slightly more than ¼ of the plate, remaining space is reserved for protein, a cup of dairy also appears, avoiding oversize portions, enjoy, but eat less, drink water

hypoglycemia

abnormally low level of sugar in the blood

food security

access to enough food to sustain a healthy and active life

nonessential amino acids

amino acids that the body can make

essential amino acids

amino acids that the body requires but cannot make, and so must be obtained from the diet

conditionally essential amino acids

an amino acid that is normally nonessential, but must be supplied by the diet in special circumstances when the need for it exceeds the body's ability to make it

PKU

an inherited disorder characterized by failure to metabolize the amino acid phenylalanine to tyrosine

nutrient deficiencies

birth defects, learning disabilities, mental retardation, impaired immunity, blindness, incapacity to work, and premature deaths are all results of _________

chronic malnutrition

caused by long-term food deprivation; characterized in children by short height for age (stunting).

acute malnutrition

caused by recent severe food restriction; characterized in children by underweight for height (wasting)

moderation

contributes to adequacy, balance, and kcalorie control; practicing includes eating such foods only on occasion and regularly selects foods low in solid fats and added sugars

less than 150

desirable blood levels for triglycerides (mg/dL)

70-99

desirable levels for fasting glucose

hyperglycemia

excessive sugar in the blood

none

fat composition of fruit/vegetables

saturated fat

fat composition of milk (think butter), refined grains

increase

foods high in saturated fats like butter and lard ______ blood cholesterol

processed foods

foods that have been treated to change their physical, chemical, microbiological, or sensory properties

balance

helps to ensure adequacy; the art of balancing the diet involving consuming enough but not too much of different types of foods in proportion to one another

digestion of carbs in the mouth

high-fiber foods stimulate salivary amylase, which begins to hydrolyze starch to shorter polysaccharides called disaccharide maltose. LITTLE DIGESTION HAPPENS IN _____.

variety

improves nutrient adequacy; people should select foods from each of the food groups daily and vary their choices within each food group

45, 65

intake of carbohydrates includes ____ to ____ % of calorie intake, between 225 and 325 grams per day

food insecurity

limited or uncertain access to foods of sufficient quality or quantity to sustain a healthy and active life

condensation

linking 2 monosaccharides together by eliminating water

requirements of a food label

listing of all ingredients, descending order of predominance by weight; nutrition facts panel has serving sizes established by the Food and Drug Administration (FDA) along with sizes listed versus USDA Food Pattern size

Converting ammonia to urea

liver detoxifies ammonia by combining it with another waste product carbon dioxide to produce urea

function of carbohydrates

main fuel for cells and muscles

kcal control

management of food energy intake; one key involves selecting foods with high nutrient density

very low food insecurity

multiple indications of disrupted eating patterns and reduced food intake; formerly known as food insecurity with hunger

high food security

no indications of food-access problems

role of protein as an enzyme

not only break down substances, but they also build substances (such as bone) and transform one substance into another (amino acids into glucose, for example)

marginal food security

one or two indications of food access problems but with little or no change in food intake

protein absorption in the stomach

partial break-down (hydrolysis) of proteins. Hydrochloric acid uncoils (denatures) each protein's tangled strands so that digestive enzymes can attack the peptide bonds. The hydrochloric acid also converts the inactive form of the enzyme pepsinogen to its active form, pepsin. Pepsin cleaves proteins—large polypeptides—into smaller polypeptides and some amino acids.

Role of protein in fluid balance

plasma proteins leak out of the blood vessels into the spaces between the cells. Be-cause proteins attract water, fluid accumulates and causes swelling. Swelling due to an excess of fluid in the tissues is known as edema

poverty

primary cause of hunger in underdeveloped countries

low food security

reduced quality of life with little or no indication of reduced food intake; formerly known as food insecurity without hunger

daily values

reference values developed by the FDA specifically for use on food labels

deamination

removal of the amino (NH2) group from a compound such as an amino acid

Kwashiorkor

severe malnutrition characterized by failure to grow and develop, edema, changes in the pigmentation of hair and skin, fatty liver, anemia, and apathy

marasmus

severe malnutrition characterized by poor growth, dramatic weight loss, loss of body fat and muscle, and apathy

resistant starch

starch that escapes digestion and absorption in the small intestine of healthy people

positive nitrogen balance

state in which the body retains more nitrogen than it loses, synthesis exceeds breakdown

nutrient claims

statements that characterize the quantity of a nutrient in a food

health claims

statements that characterize the relationship between a nutrient or other substance in a food and a disease or health-related condition

structure function claims

statements that characterize the relationship between a nutrient or other substance in a food and its role in the body

Dissacharides

sugar containing two monosaccharides

fortification

the addition to a food of nutrients that were either not originally present or present in insignificant amounts. Fortification can be used to correct or prevent a widespread nutrient deficiency or to balance the total nutrient profile of a food

enrichment

the addition to a food of specific nutrients to replace losses that occur during processing so that the food will meet a specified standard

nitrogen balance

the amount of nitrogen consumed compared with the amount excreted in a given time period

causes for protein denaturation

the change in a protein's shape and consequent loss of its function brought about by heat, agitation, acid, base, alcohol, heavy metals, or other agents

protein synthesis

the formation of proteins by using information contained in DNA and carried by mRNA

discretionary calories

the kcalories remaining in a person's energy allowance after consuming enough nutrient-dense foods to meet all nutrient needs for a day

excreting uria

the liver efficiently captures all the ammonia, makes urea from it, and releases the urea into the blood; then the kidneys clear all the urea from the blood

Gluconeogenesis

the making of glucose from a noncarbohydrate source such as amino acids or glycerol

percent daily value

the percentage of a Daily Value recommendation found in a specified serving of food for key nutrients based on a 2000-kcalorie diet

refined

the process by which the coarse parts of a food are removed. When wheat is refined into flour, the bran, germ, and husk are removed, leaving only the endosperm

transcription

the process of messenger RNA being made from a template of DNA

translation

the process of messenger RNA directing the sequence of amino acids and synthesis of proteins

role of protein as energy source

they will be sacrificed to provide energy and glucose during times of starvation or insufficient carbohydrate intake. The body will break down its tissue proteins to make amino acids available for energy or glucose production (a process known as gluconeogenesis)

process of converting nonessential amino acids

transfer amino groups (NH2) from an amino acid to a keto acid, forming a new nonessential amino acid and a new keto acid. Transamination reactions requires the vitamin B6 coenzyme.

complementary proteins

two or more dietary proteins whose amino acid assortments complement each other in such a way that the essential amino acids missing from one are supplied by the other

trans fat

unsaturated fats, composition of cookies and pastries

oral rehydration therapy

used for rehabilitation from malnutrition

fat

what carbs are stored as

muscle and liver glycogen

where carbs are stored