The amount of chemical that, if ingested
daily over a lifetime, appears to be without appreciable effect.
acesulfame K -
Acesulfame K, or acesulfame potassium,
is a low-calorie sweetener approved for use in the United States in 1988.
It is an organic salt consisting of carbon, nitrogen, oxygen, hydrogen, sulphur
and potassium atoms. It is 200 times sweeter than sucrose, has a synergistic
sweetening effect with other sweeteners, has a stable shelf-life and is heat
stable. It is excreted through the human digestive system unchanged, and is
therefore non-caloric.
additives (food additives) -
Any natural or synthetic material, other
than the basic raw ingredients, used in the production of a food item to enhance
the final product. Any substance that may affect the characteristics of any
food, including those used in the production, processing, treatment, packaging,
transportation or storage of food.
aerobic exercise -
Aerobic exercise refers to the kind of
fast-paced activity that makes you "huff and puff." It places demands
on your cardiovascular apparatus and, over time, produces beneficial changes
in your respiratory and circulatory systems.
allergen (food allergen) -
A food allergen is the part of a food
(a protein) that stimulates the immune system of food allergic individuals.
A single food can contain multiple food allergens. Carbohydrates or fats are
not allergens.
allergy (food allergy) -
A food allergy is any adverse reaction
to an otherwise harmless food or food component (a protein) that involves
the body's immune system. To avoid confusion with other types of adverse reactions
to foods, it is important to use the terms "food allergy" or "food
hypersensitivity" only when the immune system is involved in causing
the reaction.
amino acids -
Amino acids function as the building
blocks of proteins. Chemically, amino acids are organic compounds containing
an amino (NH2) group and a carboxyl (COOH) group. Amino acids are classified
as essential, nonessential and conditionally essential. If body synthesis
is inadequate to meet metabolic need, an amino acid is classified as essential
and must be supplied as part of the diet. Essential amino acids include leucine,
isoleucine, valine, tryptophan, phenylalanine, methionine, threonine, lysine,
histidine and possibly arginine. Nonessential amino acids can be synthesized
by the body in adequate amounts, and include alanine, aspartic acid, asparagine,
glutamic acid, glutamine, glycine, proline and serine. Conditionally essential
amino acids become essential under certain clinical conditions.
anemia -
Anemia is a condition in which a deficiency
in the size or number of erythrocytes (red blood cells) or the amount of hemoglobin
they contain limits the exchange of oxygen and carbon dioxide between the
blood and the tissue cells. Most anemias are caused by a lack of nutrients
required for normal erythrocyte synthesis, principally iron, vitamin B-12,
and folic acid. Others result from a variety of conditions, such as hemorrhage,
genetic abnormalities, chronic disease states or drug toxicity.
Anorexia Nervosa -
An eating disorder characterized by refusal
to maintain a minimally normal weight for height and age. The condition includes
weight loss leading to maintenance of body weight 15 percent below normal;
an intense fear of weight gain or becoming fat, despite the individual's underweight
status; a disturbance in the self-awareness of one's own body weight or shape;
and in females, the absence of at least three consecutive menstrual cycles
that would otherwise be expected to occur.
antibiotics -
Antibiotics are used in animal agriculture
for two reasons. First, to improve the rate of growth and the feed efficiency
of animals so they produce more meat or milk on less feed. The second reason
is to prevent and treat diseases, just as in humans.
antibody -
Protein produced by the immune system
of humans and higher animals in response to the presence of a specific antigen.
antigen -
A foreign substance (almost always a
protein) that, when introduced into the body, stimulates an immune response.
antioxidant -
Antioxidants protect key cell components
by neutralizing the damaging effects of "free radicals," natural
byproducts of cell metabolism. Free radicals form when oxygen is metabolized,
or burned by the body. They travel through cells, disrupting the structure
of other molecules, causing cellular damage. Such cell damage is believed
to contribute to aging and various health problems.
antisense -
A piece of DNA that produces the mirror
image, or antisense messenger RNA, that is exactly opposite in sequence to
one that directs the cells to produce a specific protein. Since the antisense
RNA binds tightly to its image, it prevents the protein from being made.
aspartame -
Aspartame is a low-calorie sweetener
used in a variety of foods and beverages and as a tabletop sweetener. It is
about 200 times sweeter than sugar. Aspartame is made by joining two protein
components, aspartic acid and phenylalanine.
asthma -
Asthma is a chronic medical condition,
affecting approximately 10 million Americans (3 to 4 percent of the population).
Asthma results when irritants (or trigger substances) cause swelling of the
tissues in the air passage of the lungs, making it difficult to breathe. Typical
symptoms of asthma include wheezing, shortness of breath and coughing.
atherosclerosis -
A condition that exists when too much
cholesterol builds up in the blood and accumulates in the walls of the blood
vessels.
Commonly called "hyperactivity,"
Attention Deficit Hyperactivity Disorder is a clinical diagnosis based on
specific criteria. These include excessive motor activity, impulsiveness,
short attention span, low tolerance to frustration and onset before 7 years
of age.
Bias occurs when problems in study design
lead to effects that are not related to the variables being studied. An example
is selection bias, which occurs when study subjects are chosen in a way that
can misleadingly increase or decrease the strength of an association. Choosing
experimental and control group subjects from different populations would result
in a selection bias.
biopesticide -
A biopesticide is any material of natural
origin used in pest control derived from living organisms, such as bacteria,
plant cells or animal cells.
biotechnology -
The simplest definition of biotechnology
is "applied biology." The application of biological knowledge and
techniques to develop products. It may be further defined as the use of living
organisms to make a product or run a process. By this definition, the classic
techniques used for plant and animal breeding, fermentation and enzyme purification
would be considered biotechnology. Some people use the term only to refer
to newer tools of genetic science. In this context, biotechnology may be defined
as the use of biotechnical methods to modify the genetic materials of living
cells so they will produce new substances or perform new functions. Examples
include recombinant DNA technology, in which a copy of a piece of DNA containing
one or a few genes is transferred between organisms or "recombined"
within an organism.
blind (single or double) experiment
-
In a single blind experiment, the subjects
do not know whether they are receiving an experimental treatment or a placebo.
In a double blind experiment, neither the researchers nor the participants
are aware of which subjects receive the treatment - until after the study
is completed.
Bovine spongiform encephalopathy, or
BSE, is also known as "mad cow disease." It is a rare, chronic degenerative
disease affecting the brain and central nervous system of cattle. Cattle with
BSE lose their coordination, develop abnormal posture and experience changes
in behavior. Clinical symptoms take 4-5 years to develop, followed by death
in a period of several weeks to months unless the affected animal is destroyed
sooner.
rBST (bovine somatotropin) -
Recombinant bovine somatotropin (rBST)
is virtually identical to a cow's natural somatotropin, a hormone produced
in its pituitary gland that stimulates milk production. Treatment with rBST
can increase a cow's milk production by 10 percent to 15 percent.
Bt (Bacillus thuringiensis)
-
One of the most common microorganisms
used in biologically-based pesticides is the Bacillus thuringiensis or Bt
bacterium. Several of the proteins produced by the Bt, principally in the
coating the bacteria forms around itself, are lethal to individual species
of insects. By using Bt in pesticide formulations, target insects can be controlled
using an environmentally benign, biologically-based agent. Bt-based insecticides
have been widely used by home gardeners for many years as well as on farms.
Bulimia Nervosa -
An eating disorder characterized by rapid
consumption of a large amount of food in a short period of time, with a sense
of lack of control during the episode and self-evaluation unduly influenced
by body weight and shape. There are two forms of the condition, purging and
non-purging. The first type regularly engages in purging through self-induced
vomiting or the excessive use of laxatives or diuretics. Alternatively, the
non-purging type controls weight through strict dieting, fasting or excessive
exercise.
A calorie is the amount of energy required
to raise the temperature of one milliliter (ml) of water at a standard initial
temperature by one degree centigrade (¡C).
caffeine -
Caffeine is a naturally-occurring substance
found in the leaves, seeds or fruits of over 63 plant species worldwide and
is part of a group of compounds known as methylxanthines. The most commonly
known sources of caffeine are coffee and cocoa beans, cola nuts and tea leaves.
Caffeine is a pharmacologically active substance and, depending on the dose,
can be a mild central nervous system stimulant. Caffeine does not accumulate
in the body over the course of time and is normally excreted within several
hours of consumption.
Carbohydrates are organic compounds that
consist of carbon, hydrogen and oxygen. They vary from simple sugars containing
from three to seven carbon atoms to very complex polymers. Only the hexoses
(sugars with six carbon atoms) and pentoses (sugars with five carbon atoms)
and their polymers play important roles in nutrition. Carbohydrates in food
provide 4 calories per gram.
Plants manufacture and store carbohydrates as their chief source of
energy. The glucose synthesized in the leaves of plants is used as the basis
for more complex forms of carbohydrates. Classification of carbohydrates relates
to their structural core of simple sugars, saccharides. Principal monosaccharides
that occur in food are glucose and fructose. Three common disaccharides are
sucrose, maltose and lactose. Polysaccharides of interest in nutrition include
starch, dextrin, glycogen and cellulose.
The CDC, composed of 11 Centers, Institutes
and Offices, aims to promote health and quality of life by preventing and
controlling disease, injury and disability.
cholesterol (dietary) -
Cholesterol is not a fat, but rather
a fat-like substance classified as a lipid. Cholesterol is vital to life and
is found in all cell membranes. It is necessary for the production of bile
acids and steroid hormones. Dietary cholesterol is found only in animal foods.
Abundant in organ meats and egg yolks, cholesterol is also contained in meats
and poultry. Vegetable oils and shortenings are cholesterol-free.
cholesterol (serum, or blood)
-
High blood cholesterol is a risk factor
in the development of coronary heart disease. Most of the cholesterol that
is found in the blood is manufactured by the body, in the liver, at a rate
of about 800 to 1,500 milligrams a day. By comparison, the average American
consumes 300 to 450 milligrams daily in foods.
cholesterol (different types)
-
Blood cholesterol is divided into three
separate classes of lipoproteins: very-low density lipoprotein (VLDL); low-density
lipoprotein (LDL), which contains most of the cholesterol found in the blood;
and high-density lipoprotein (HDL).
LDL seems to be the culprit in coronary heart disease and is popularly
known as the "bad cholesterol." By contrast, HDL is increasingly
considered desirable and known as the "good cholesterol."
chromosome -
Thread-like components in the cell that
contain DNA. They make proteins. Genes are carried on the chromosomes.
clinical trials -
Clinical trials undertake experimental
study of human subjects. Trials may attempt to determine whether the finds
of basic research are applicable to humans, or to confirm the results of epidemiological
research. Studies may be small, with a limited number of participants, or
they may be large intervention trials that seek to discover the outcome of
treatments on entire populations. The "gold standard" clinical trials
are double-blind, placebo-controlled studies which employ random assignment
of subjects to experimental and control groups unknown to the subject or the
researcher.
confounding variable or confounding
factor -
A "hidden" variable that may
cause an association which the researcher attributes to other variables.
Continuing Survey of Food Intake
of Individuals (CSFII) -
A part of the National Nutrition Monitoring
System which was the first nationwide dietary intake survey designed to be
conducted annually. The survey is conducted by the USDA.
control group -
The group of subjects in a study to whom
a comparison is made in order to determine whether an observation or treatment
has an effect. In an experimental study it is the group that does not receive
a treatment. Subjects are as similar as possible to those in the test or treatment
group.
controlled experiment -
In this type of research, study subjects
(whether animal or human) are selected according to relevant characteristics,
and then randomly assigned to either an experimental group, or a control group.
Random assignment ensures that factors known as variables, which may affect
the outcome of the study, are distributed equally among the groups and therefore
could not lead to differences in the effect of the treatment under study.
The experimental group is then given a treatment (sometimes called an intervention),
and the results are compared to the control group, which does not receive
treatment. A placebo, or false treatment, may be administered to the control
group. With all other variables controlled, differences between the experimental
and control groups may be attributed to the treatment under study.
correlation -
An association, or when one phenomenon
is found to be accompanied by another. A correlation does not prove cause
and effect. Correlation may also be defined statistically.
Popularly known as cavities, dental caries
occur when bacteria in the mouth feed on fermentable carbohydrates and produce
acids that dissolve tooth enamel. Various conditions affect this process,
such as heredity and the composition and flow of saliva. Any fermentable carbohydrate
(starches and sugars) can serve as food for cavity-causing bacteria. The amount
of carbohydrate is not as important as how often these foods are eaten and
how long they stay in the mouth. Widespread use of fluoride in water supplies
and oral health products is credited with the dramatic decline in dental caries
among children and adults alike over the past 20 years. Also, see "fluoride."
diabetes -
Diabetes is the name for a group of medical
disorders characterized by high blood sugar levels. Normally when people eat,
food is digested and much of it is converted to glucose -- a simple sugar
-- which the body uses for energy. The blood carries the glucose to cells
where it is absorbed with the help of the hormone insulin. For those with
diabetes, however, the body does not make enough insulin, or cannot properly
use the insulin it does make. Without insulin, glucose accumulates in the
blood rather than moving into the cells. High blood sugar levels result.
DNA -
Also known as Deoxyribonucleic acid.
This is the molecule that carries the genetic information for most living
systems. The DNA molecule consists of four bases (adenine, cytosine, guanine
and thymine) and a sugar-phosphate backbone, arranged in two connected strands
to form its characteristic double-helix.
double-blind, placebo-controlled
study -
In a double-blind, placebo controlled
study, neither the researchers nor the participants in the study are aware
of which subjects receive the treatment under study and which subjects receive
the placebo until after the study is completed. The study design is intended
to remove bias on the part of both researcher and study subject.
The bacteria Escherichia coli: O157:H7
is a type of E. coli associated with foodborne illness. Healthy cattle and
humans can carry the bacteria. It can be transferred from animal to animal
and animal to human, and from animal to human on food. Transmission from person
to person through close contact is a potential problem, especially among young
children in daycare.
Environmental Protection Agency
(EPA) -
The EPA's mission is to protect human
health and safeguard the natural environment - air, water and land - upon
which life depends. Through regulation, EPA tries to ensure the human population
and the environment are protected from environmental risks and exposures.
epidemiology -
The study of distribution and determinants
of diseases or other health outcomes in human populations. It seeks to expose
potential associations between aspects of health (such as cancer, heart disease,
etc.) and diet, lifestyle, habits or other factors within populations. Epidemiological
studies may suggest relationships between two factors, but do not provide
the basis for conclusions about cause and effect. Possible associations inferred
from epidemiological research can turn out to be coincidental.
experimental group -
The group of subjects in an experimental
study which receives a treatment.
Fats are referred to in the plural because
there is no one type of fat. Fats are composed of the same three elements
as carbohydrates -- carbon, hydrogen and oxygen, However, fats have relatively
more carbon and hydrogen and less oxygen, thus supplying a higher fuel value
of nine calories per gram (versus four calories per gram from carbohydrates
and protein).
One molecule of fat can be broken down into three molecules of fatty
acids and one molecule of glycerol. Thus, fats are known chemically as triglycerides.
Fats are a vital nutrient in a healthy diet. Fats supply essential fatty
acids, such as linoleic acid, which is especially important to childhood growth.
Fat helps maintain healthy skin, regulate cholesterol metabolism and is a
precursor of prostaglandins, hormone-like substances that regulate some body
processes. Dietary fat is needed to carry fat-soluble vitamins A, D, E and
K and to aid in their absorption from the intestine.
fatty acid -
Fatty acids are generally classified
as saturated, monounsaturated or polyunsaturated. These terms refer to the
number of hydrogen atoms attached to the carbon atoms of the fat molecule.
In general, fats that contain a majority of saturated fatty acids are solid
at room temperature, although some solid vegetable shortenings are up to 75
percent unsaturated. Fats containing mostly unsaturated fatty acids are usually
liquid at room temperature and are called oils. Also, see "fats",
or "hydrogenation."
fiber -
Dietary fiber generally refers to parts
of fruits, vegetables, grains, nuts and legumes that can't be digested by
humans. Meats and dairy products do not contain fiber. Studies indicate that
high-fiber diets can reduce the risks of heart disease and certain types of
cancer. There are two basic types of fiber - insoluble and soluble. Soluble
fiber in cereals, oatmeal, beans and other foods has been found to lower blood
cholesterol. Insoluble fiber in cauliflower, cabbage and other vegetables
and fruits helps move foods through the stomach and intestine, thereby decreasing
the risk of cancers of the colon and rectum.
5 A Day -
Refers to the dietary recommendation
to consume five servings of fruits and vegetables every day. The tagline,
5 A Day, became a promotional message in campaigns to increase fruits and
vegetable consumption.
Fluoride is a natural component of minerals
in rocks and soils. Widespread use of fluoride in water supplies and oral
health products is credited with the dramatic decline in dental caries among
children and adults alike. All water contains fluoride, but it is sometimes
necessary to add it to some public supplies to attain the optimal amount for
dental health. Fluoride makes tooth enamel stronger and more resistant to
decay. It also prevents the growth of harmful bacteria and interferes with
converting fermentable carbohydrates to acids in the mouth.
Folic acid, folate, folacin, all form
a group of compounds functionally involved in amino acid metabolism and nucleic
acid synthesis. Good dietary sources of folate include leafy, dark green vegetables,
legumes, citrus fruits and juices, peanuts, whole grains and fortified breakfast
cereals.
Recent studies show, if all women of childbearing age consumed sufficient
folic acid (either through diet or supplements), 50 to 70 percent of birth
defects of the brain and spinal cord could be prevented, according to the
U.S. Centers for Disease Control and Prevention (CDC.) Folic acid is critical
from conception through the first four to six weeks of pregnancy when the
neural tube is formed. This means adequate diet or supplement use should begin
before pregnancy occurs.
Recent research findings also show low blood folate levels can be associated
with elevated plasma homocysteine and increased risk of coronary heart disease.
Food and Drug Administration
(FDA) -
The Food and Drug Administration is part
of the Public Health Service of the U.S. Department of Health and Human Services.
It is the regulatory agency responsible for ensuring the safety and wholesomeness
of all foods sold in interstate commerce except meat, poultry and eggs (which
are under the jurisdiction of the U.S. Department of Agriculture). FDA develops
standards for the composition, quality, nutrition, safety and labeling of
foods including food and color additives. It conducts research to improve
detection and prevention of contamination. It collects and interprets data
on nutrition, food additives and pesticide residues. The agency also inspects
food plants, imported food products and feed mills that make feeds containing
medications or nutritional supplements that are destined for human consumption.
And it regulates radiation-emitting products such as microwave ovens. FDA
also enforces pesticide tolerances established by the Environmental Protection
Agency for all domestically produced and imported foods, except for foods
under USDA jurisdiction.
Food Guide Pyramid -
The Food Guide Pyramid is a graphic design
used to communicate the recommended daily food choices contained in the Dietary
Guidelines for Americans. The information provided was developed and promoted
by the U.S. Department of Agriculture and the U.S. Department of Health and
Human Services.
foodborne disease -
Disease, usually gastrointestinal, caused
by organisms or their toxins carried in ingested food. Also commonly known
as "food poisoning."
food irradiation -
The exposure of food to sufficient radiant
energy (gamma rays, x-rays and electron beams) to destroy microorganisms and
insects. Irradiation is used in food production and processing to promote
food safety.
fructose -
Fructose is a monosaccharide found naturally
in fruits, as an added sugar in a crystalline form and as a component of high-fructose
corn syrup (HFCS).
fruit -
Fruit is the usually edible reproductive
body of a seed plant, especially one having a sweet pulp associated with the
seed.
Foods that may provide health benefits
beyond basic nutrition. Examples include tomatoes with lycopene, thought to
help prevent the incidence of prostate and cervical cancers; fiber in wheat
bran and sulfur compounds in garlic also believed to prevent cancer.
The study and appreciation of good food
and good eating, and a culture's culinary customs, style and lore. Any interest
or study of culinary pursuits as relates essentially to the kitchen and cookery,
and to the higher levels of education, training and achievement of the chef
apprentice or professional chef.
generalizability -
The extent to which the results of a
study are able to be applied to the general population of people that is comparable
to the population studied.
genome -
The total hereditary material of a cell,
containing the entire chromosomal set found in each nucleus of a given species.
glucose -
A sugar, most commonly in the form of
dextroglucose, that occurs naturally, has about half the sweetening power
of regular sugar and does not crystallize easily. Glucose comes from grape
juice, honey and certain vegetables, among other things.
Glutamate is an amino acid. It is necessary
for metabolism and brain function, and is manufactured by the body. Glutamate
is found in virtually every protein food we eat. In food, there is "bound"
glutamate and "free" glutamate. Glutamate serves to enhance flavors
in foods when it is in its free form and not bound to other amino acids in
protein. Some foods have greater quantities of glutamate than others. Foods
that are rich in glutamate include tomatoes, mushrooms, parmesan cheese, milk
and mackerel.
glycerol -
A colorless, odorless, syrupy liquid
- chemically, an alcohol - that is obtained from fats and oils and used to
retain moisture and add sweetness to foods.
grains -
Grains are the seeds or fruits of various
food plants including cereal grasses. The examples of wheat, corn, oats, barley,
rye and rice provide a partial list. Grain foods include foods such as bread,
cereals, rice and pasta.
GRAS (Generally Recognized as
Safe) -
GRAS is the regulatory status of food
ingredients not evaluated by the FDA prescribed testing procedure. It also
includes common food ingredients that were already in use when the 1959 Food
Additives Amendment to the Food, Drug and Cosmetic Act was enacted.
HACCP (Hazard Analysis and Critical
Control Points) -
The underlying approach under HACCP for
preventing foodborne illness and promote quality is to identify the danger
spots and try to avoid them. Instead of putting the burden on government to
discover that a food safety problem exists, HACCP shifts responsibility onto
the industry to ensure that the food it produces is safe. Food producers will
have to prevent bacterial contamination from occurring in the first place.
HACCP works by the following principles:
Identify the likely health hazards
to consumers in a given product.
Identify the critical points in the
processing where the hazards may occur.
Establish safety measures to prevent
the hazard from occurring.
Monitor to make sure the safety measures
are working.
Establish an appropriate remedy if
monitoring shows a problem.
Establish detailed record keeping
to document monitoring and remedies taken.
Verify that the whole system is working.
herbicides -
Herbicides are a class of crop protection
and specialty chemicals used to control weeds on farms and in forests, as
well as in non-agricultural applications such as golf courses, public tracts
of land and residential lawns.
high-fructose corn syrup (HFCS)
-
HFCS are formulations generally containing
42 percent, 55 percent or 90 percent fructose (the remaining carbohydrate
being primarily glucose) depending on the product application. HCFS are used
in products such as soft drinks or cake mixes.
Hydrogenation is the process of adding
hydrogen molecules directly to an unsaturated fatty acid from sources such
as vegetable oils to convert it to a semi-solid form such as margarine or
shortening. Hydrogenation contributes important textural properties to food.
The degree of hydrogenation influences the firmness and spreadability of margarines,
flakiness of pie crust and the creaminess of puddings. Hydrogenated oils are
sometimes used in place of other fats with higher proportions of saturated
fatty acids such as butter or lard.
Hypertension is the persistently elevated
arterial blood pressure. It is the most common public health problem in developed
countries. Emphasis on lifestyle modifications has given diet a prominent
role for both the primary prevention and management of hypertension.
The number of new cases of a disease
during a given period of time in a defined population.
insecticide -
Insecticides are a class of crop protection
and specialty chemicals used to control insects on farms and forests, as well
as non-agricultural applications such as residential lawncare, golf courses
and public tracts of land.
integrated pest management (IPM)
-
Integrated pest management is the coordinated
use of pest and environmental information along with available pest control
methods, including cultural, biological, genetic and chemical methods, to
prevent unacceptable levels of pest damage using the most economical means,
and with the least possible hazard to people, property and the environment.
A sugar naturally occurring in milk,
also known as "milk sugar," that is the least sweet of all natural
sugars and used in baby formulas and candies.
lactose intolerance -
Lactose intolerance is an inherited inability
to properly digest dairy products, due to a deficiency in the amount of the
enzyme, §-galactosidase in the small intestine. This enzyme is necessary for
the hydrolysis of lactose (a disaccharide) into its constituent monosaccharides,
glucose and galactose. Symptoms of lactose intolerance, including abdominal
cramps, flatulence and frothy diarrhea, can increase with age.
listeria -
Listeria monocytogenes is a Gram-positive
bacterium, found in at least 37 mammalian species, as well as 17 species of
birds and possibly some fish and shellfish. The bacteria can be isolated from
soil, and is resistant to heat, freezing and drying.
Listeria has been associated with foods such as raw milk, soft-ripened
cheeses, ice cream, raw vegetables, raw and cooked poultry, raw meat and raw
and smoked fish. Unlike other pathogenic bacteria, such as salmonella, listeria
can survive and grow at temperatures as low as 5¡C (41¡F).
Acute infection with listeria may result in flu-like symptoms including
persistent fever, followed by septicemia, meningitis, encephalitis, and intrauterine
or cervical infections in pregnant women. Possible gastrointestinal symptoms
include nausea, vomiting and diarrhea, alone or couple with other symptoms
(mentioned above).
Low-calorie sweeteners are non-nutritive
sweeteners, also referred to as intense sweeteners. Low-calorie sweeteners
can replace nutritive sweeteners in most foods at a caloric savings of approximately
16 calories per teaspoon. Thus, caloric reduction may be achieved when low-calorie
sweetened foods and beverages are substituted for their full-calorie counterparts.
Examples of low-calorie sweeteners in use in the U.S. food supply are saccharin,
aspartame and acesulfame K.
lycopene -
Lycopene is a carotenoid related to the
better known beta-carotene. Lycopene gives tomatoes and some other fruits
and vegetables their distinctive red color. Nutritionally, it functions as
an antioxidant. Research shows lycopene is best absorbed by the body when
consumed as tomatoes that have been heat-processed using a small amount of
oil. This includes products such as tomato sauce and tomato paste. Also, see
functional foods.
MSG is the sodium salt of glutamic acid.
Glutamic acid, or glutamate, is one of the most common amino acids found in
nature. (see glutamate)
In the early part of the century, MSG was extracted from seaweed and
other plant sources. Today, MSG is produced in many countries around the world
through a fermentation process of molasses from sugar cane or sugar beets,
as well as starch and corn sugar.
morbid obesity -
This is a state of adiposity or overweight,
in which body weight is 100 percent above the ideal and a body mass index
of 45 or greater.
A survey conducted by the USDA roughly
every ten years that monitors the nutrient intake of a cross-section of the
U.S. public.
National Health and Nutrition
Examination Survey (NHANES) -
A series of surveys that include information
from medical history, physical measurements, biochemical evaluation, physical
examination and dietary intake of population groups within the United States.
The NHANES is conducted by the U.S. Department of Health and Human Services
approximately every five years.
In simple terms, a neural tube defect
(NTD) is a malformation of the brain or spinal cord (neurological system)
during embryonic development. Infants born with spina bifida, where the spinal
cord is exposed, can grow to adulthood but usually suffer from paralysis or
other disabilities. Babies born with anencephaly, where most or all of the
brain is missing, usually die shortly after birth. These NTDs make up about
5 percent of all U.S. birth defects each year.
According to the CDC, the use of sufficient folic acid is enough to
eliminate the risk of NTDs. (see folic acid)
Nitrite is a safe food additive that
has been used for centuries to preserve meats, fish and poultry. It also contributes
to the characteristic flavor, color and texture of processed meats such as
hot dogs. Because nitrite safeguards cured meats against the most deadly foodborne
bacterium of all, Clostridium (C.) botulinum, its use is supported by the
public health community.
The human body generates much greater nitrite levels than are added
to food. Nitrates consumed in foods such as carrots and green vegetables are
converted to nitrite during digestion. Nitrite in the body is instrumental
in promoting blood clotting, healing wounds and burns, and boosting immune
function to kill tumor cells.
nitrosamines -
Nitrosamines are a digestive reaction-product
of nitrite, a food additive used to preserve meats, fish and poultry. (Also
see nitrite.)
nutraceuticals -
One term used to describe substances
in or parts of a food that may be considered to provide medical or health
benefits beyond basic nutrition, including disease prevention. Research indicates
this term might not appeal to consumers. Also, see "functional
foods."
Although precise definitions vary among
experts, overweight has been traditionally defined as 10 percent to 20 percent
above an optimal weight for height derived from statistics. Obesity is defined
as body weight being 20% above normal. Some scientists argue that the amount
and distribution of an individual's body fat is a significant indicator of
health risk and therefore should be considered in defining overweight. Abdominal
fat has been linked to more adverse health consequences than fat in the hips
or thighs. Thus, calculations of waist-to-hip ratio are preferred by some
health experts to help determine if an individual is overweight.
organic -
Organic defines agricultural products
that are grown using cultural, biological and mechanical methods prior to
the use of synthetic, non-agricultural substances to control pests, improve
soil quality an/or enhance processing. The USDA is currently addressing the
issue of organic products, and aims to have official rules for what may be
considered organic ready for the 1999 spring planting season.
Currently organic defines an agricultural process in which farmers use
techniques such as crop rotation, cultivation, mulching, soil enrichment and
the "encouragement" of predators and microorganisms which naturally
keep pests away. The now widely accepted definition allows farmers to use
natural pesticides, but nothing synthetic.
osteoporosis -
Osteoporosis is a skeletal disease in
which the bones lose mass and density, the pores in bones enlarge, and the
bones generally become fragile. Osteoporosis often is not diagnosed until
a fracture occurs, most commonly in the spine, hip or wrist. The National
Osteoporosis Foundation estimates that about 1.5 million such fractures occur
each year in the United States, at an estimated annual cost of $14 billion
in 1995.
Osteoporosis is four times more common in women, whose bones are naturally
thinner and less dense, than in men. Women start losing bone mass and density
at an earlier age, and the process is accelerated by menopause, causing osteoporosis
to manifest itself between the ages of 50 and 60. Research has shown that
in addition to regular exercise, calcium intake during childhood, adolescence
and early-adulthood helps build a "bone bank" of calcium stores.
While bone length is established by age 20, bone strength and density continue
to develop through age 30.
outcomes research -
A type of research increasingly used
by the health industry which provides information about how a specific procedure
or treatment regimen results: the subject (clinical safety and efficacy),
the subject's physical functioning and lifestyle, and economic considerations
such as saving/prolonging life and avoiding costly complications.
A broad class of crop protection chemicals
including four major types: insecticides used to control insects; herbicides
used to control weeds; rodenticides used to control rodents; and fungicides
used to control mold, mildew and fungi.
In addition consumers use pesticides in the home or yard to control
termites and roaches, clean mold from shower curtains, stave off crab grass
on the lawn, kill fleas and ticks on pets and disinfect swimming pools, to
name just a few "specialty" pesticide uses.
phytochemical -
Phytochemicals are substances found in
edible fruits and vegetables that may be ingested by humans daily in gram
quantities and that exhibit a potential for modulating the human metabolism
in a manner favorable for reducing risk of cancer. (see functional
foods)
placebo -
Sometimes casually referred to as a "sugar
pill," a placebo is a "fake" treatment which seems identical
to the real treatment. Placebo treatments are used to eliminate bias that
may arise from the expectation that a treatment should produce an effect.
prevalence -
The number of existing cases of a disease
in a defined population at a specified time.
prion -
A prion is a rogue protein, that appears
to cause Bovine spongiform encephalopathy (BSE).
prospective study -
Epidemiological research that follows
a group of people over a period of time to observe the potential effects of
diet, behavior and other factors on health or the incidence of disease. In
general, this is considered a more valid research design than retrospective
research.
protein -
Chemically, a protein is a complex nitrogenous
compound made up of amino acids in peptide linkages. Dietary proteins are
involved in the synthesis of tissue protein and other special metabolic functions.
In anabolic processes they furnish the amino acids required to build and maintain
body tissues. As an energy source, proteins are equivalent to carbohydrates
in providing 4 calories per gram. Proteins perform a major structural role
in all body tissues and in the formation of enzymes, hormones and various
body fluids and secretions. Proteins participate in the transport of some
lipids, vitamins and minerals and help maintain the body's homeostasis.
A process of assigning subjects to experimental
or control groups in which the subjects have an equal chance of being assigned
to each group. Randomization is used to control for known, unknown and difficult-to-control-for
variables.
random sample -
A random sample is a procedure to select
subjects for a study in which all individuals in a population being studied
have an equal chance of being selected. using a random sample allows the results
of the study to be generalized to the entire population.
The term random also applies to assignments within controlled studies,
or the division of subjects into groups. Random assignment ensures that all
subjects have an equal chance of being in the experimental and control groups,
and increases the probability that any unidentified variable will systematically
occur in both groups with the same frequency. Randomization is crucial to
control for variables that researchers may not be aware of or cannot adequately
control, but which could affect the outcome of an experimental study.
random sampling -
A method by which subjects are selected
to participate in a study in which all individuals in a population have and
equal chance of being chosen. This helps to ensure the generalizability of
the study results.
rapid assays -
These diagnostic tests use emerging technology
to identify and remove impurities from foods before they reach the consumer.
There are two major types of rapid assays.
Antibody-based assays link a "familiar" characteristic on
a pathogen's surface (the antigen) to a substance known as an antibody. When
this connection is made, the test registers "success." Similarly,
nucleic acid-based assays use the unique genetic materials of the cells to
detect a pathogen.
recombinant DNA (rDNA) -
The DNA formed by combining segments
of DNA from different organisms.
reliability -
Whether a test or instrument used to
collect data, such as a questionnaire, gives the same results if repeated
on the same person several times. A reliable test gives reproducible results.
research design -
How a study is set up to collect information,
or data. For valid results, the design must be appropriate to answer the question
or hypothesis being studied.
residual confounding -
The effect that remains after one has
attempted to statistically control for variables that cannot be measured perfectly.
A particularly important concept in epidemiological studies because knowledge
of human biology is still developing. Unknown variables could exist that could
significantly change conclusions made on the basis of epidemiological research.
retrospective study -
Research that relies on recall of past
data, or on previously recorded information. Often this type of research is
considered to have limitations, because the number of variables that cannot
be controlled, and because memory is not infallible.
risk -
A term encompassing a variety of measures
of the probability of an outcome. It's usually used in reference to unfavorable
outcomes such as illness or death. Be certain to distinguish between absolute
and relative risk.
risk factor -
A risk factor is anything statistically
shown to have a relationship with the incidence of a disease, however it does
not necessarily infer cause and effect.
RNA -
Also known as ribonucleic acid. RNA is
a molecule similar to DNA that functions primarily to decode the instructions
carried by genes for protein synthesis.
Saccharin, the oldest of the non-nutritive
sweeteners, is currently produced from purified, manufactured methyl anthranilate,
a substance occurring naturally in grapes. It is 300 times sweeter than sucrose,
heat stable and does not promote dental caries. Saccharin has a long shelf
life, but a slightly bitter aftertaste. It is not metabolized in the human
digestive system, is excreted rapidly in the urine and does not accumulate
in body.
salmonella -
Salmonella is a Gram-negative bacterium,
occurring in many animals, especially poultry and swine. In the environment,
salmonella can be found in water, soil, insects, factory and kitchen surfaces,
animal fecal matter, and raw meats, poultry (including eggs) and seafood.
Acute symptoms of the illness caused by the Salmonella species include
nausea, vomiting, diarrhea, abdominal cramps, headache and fever.
spina bifida -
Spina bifida is a birth defect in which
the infant is born with the spinal cord exposed. These children can grow to
adulthood although they often suffer from paralysis and other disabilities.
Also, see "neural tube defects (NTDs)."
statistical power -
A mathematical quantity that indicates
the probability a study has of obtaining a statistically significant effect.
A high power of 80 percent, or 0.8, indicates that the study - if conducted
repeatedly - would produce a statistically significant effect 80 percent of
the time. On the other hand, a power of only 0.1 means there would be a 90
percent chance that the research missed the effect - if one exists at all.
statistical significance -
The probability of obtaining an effect
or association in a study sample as or more extreme that the one observed
if there was actually no effect in the population. Based on the hypothesis
that if there truly is no effect, the results of a study are unlikely to have
occurred. A P value of less than five percent (P<0.05) means the result
would occur less than five percent of the time if there were no effect, and
is generally considered evidence of a true treatment effect or a true relationship.
sucralose -
Sucralose is the only low-calorie sweetener
that is made from sugar. It is approximately 600-times sweeter and does not
contain calories. Sucralose is highly stable under a wide variety of processing
conditions. Thus, it can be used virtually anywhere sugar can, including cooking
and baking, without losing any of its sugar-like sweetness.
Currently, sucralose is approved in over 25 countries around the world
for use in food and beverages. In the US, the FDA has been petitioned to approve
the use of sucralose in 15 different food and beverage categories.
sucrose -
Sucrose, a type of sugar, is a diglyceride
composed of glucose and fructose. Also, see "carbohydrates."
sugar -
Although the consumer is confronted by
a wide variety of sugars -- sucrose, raw sugar, turbinado sugar, brown sugar,
honey, corn syrup -- there is no significant difference in the nutritional
content or energy each provides, and therefore no advantage of one nutritionally
over another. There also is no evidence that the body can distinguish between
naturally occurring or added sugars in food products.
Trans fats occur naturally in beef, butter,
milk and lamb fats and in commercially prepared, partially hydrogenated margarines
and solid cooking fats. The main sources of trans fats in the American diet
today are margarine, shortening, commercial frying fats and high-fat baked
goods.
Partially hydrogenated vegetable oils were developed in part to help
displace highly saturated animal and vegetable fats used in frying, baking
and spreads. However, trans fats, like saturated fats, may raise blood LDL
cholesterol levels (the so-called "bad" cholesterol) - but not as
much as the saturates do. At high consumption, levels may also reduce the
HDL or "good" cholesterol levels.
In addition to the four main taste components
(sweet, sour, salty and bitter), there is the additional taste characteristic
called "umami" or savory. One of the food components responsible
for the umami flavor in foods is glutamate, an amino acid. Also, see "glutamate"
and "MSG."
U.S. Department of Agriculture
(USDA) -
The United States Department of Agriculture
comprises of many agencies charged with different tasks related to agriculture
and our food supply. Among these is ensuring a safe, affordable, nutritious
and accessible food supply. The USDA also enhances the quality of life for
the American population by supporting production of agricultural products;
caring for agricultural, forest and range lands; supporting sound development
of our rural communities; providing economic opportunities for farm and rural
residents; expanding global markets for agricultural and forest products and
services; and working to reduce hunger in America and throughout the world.
The extent to which a study or study
instrument measures what it is intended to measure. Refers to accuracy or
truthfulness in regard to a study's conclusion.
variable -
Any characteristic that may vary in study
subjects, such as gender, age, body weight, diet, behavior, attitude or other
attribute. In an experiment, the treatment is called the independent variable;
it is the factor being investigated. The variable that is influenced by the
treatment is the dependent variable; it may change as a result of the effect
of the independent variable.
vegetarian -
According to the Vegetarian Resource
Group, less than 1 percent of Americans are true vegetarians. Such people
never eat meat, fish or poultry, although they may eat foods derived from
animals such as dairy products and eggs (lacto-ovo vegetarians). There are
even fewer vegans, strict vegetarians who avoid all animal-derived foods --
even honey.
vitamins -
Vitamins are organic compounds that are
nutritionally essential in small amounts to control metabolic processes and
cannot be synthesized by the body. Vitamins are usually classified by their
solubility, which to some degree determines their stability; occurrence in
foodstuffs; distribution in body fluids, and tissue storage capacity.
Each of the fat-soluble vitamins A, D, E and K has a distinct and separate
physiologic role. Several have antioxidant properties to depress the effects
of metabolic byproducts called free radicals, which are thought to cause degenerative
changes related to aging.
Most of the water-soluble vitamins are components of essential enzyme
systems. Many are involved in the reactions supporting energy metabolism.
These vitamins are not normally stored in the body in appreciable amounts
and are normally excreted in the urine. Thus, a daily supply is desirable
to avoid depletion and interruption of normal physiologic functions.
Although deficiencies of energy or nutrients
can be sustained for months or even years, a person can survive only a few
days without water. Experts rank water second only to oxygen as essential
for life. In addition to offering true refreshment for the thirsty, water
plays a vital role in all bodily processes. It supplies the medium in which
various chemical changes of the body occur, aiding in digestion, absorption,
circulation and lubrication of body joints. For example, as a major component
of blood, water helps deliver nutrients to body cells and removes waste to
the kidneys for excretion.
WIC -
Special Supplemental Nutrition Program
for Women, Infants, and Children. Established in 1972, the WIC program provides
food and nutrition education to improve the nutritional status of medically
high-risk pregnant and lactating women and children up to 5 years of age from
low-income families. The program is administered by the U.S. Department of
Agriculture.
Synthetic chemicals believed to be resistant
to environmental degradation. A branch of biotechnology called bioremediation
is seeking to develop biological methods to degrade such compounds.
