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ESSAY SAMPLE ON "THE HISTORY, USE, AND EFFECTIVENESS OF MEDICINAL DRUGS." |
The History, Use, and Effectiveness of Medicinal Drugs
I. The History, Use, and Effectiveness of Medicinal Drugs
A. Introduction (Pg's
1-2)
II. Aspirin
(Pg's 3-6)
A. Its Origin
B. Dosages
C. Relative Effectiveness
D. Side Effects
E. Alternate Treatment
III. Sulfa Drugs
(Pg's 7-10)
A. Its Origin
B. Dosages
C. Relative Effectiveness
D. Side Effects
E. Alternate Treatment
IV. Antibiotics
(Pg's 11-14)
A. Its Origin
B. Dosages
C. Relative Effectiveness
D. Side Effects
E. Alternate Treatment
V. Antihistamines
(Pg's
15-17)
A. Its Origin
B. Dosage and Use
C. Relative Effectiveness
D. Side Effects
E. Alternate Treatment
VI. History, Use and Effectiveness of Vitamins (Pg's 18-31)
and Nutrient Supplements
VII. Future Prospects and Trends in Pharmacology (Pg's 32-42)
VIII. Recipe
(Pg's 43-44) Endnotes
(Pg's 45-46) Bibliography
(Pg's 47-48)
THE HISTORY, USE, AND EFFECTIVENESS
OF MEDICINAL DRUGS
The science and ambidexterity of treating, diagnosing, and preventing disease is known
as
the field of Medicine. In ancient times Medicine was a vague field, mostly incorporated
with magic and superstition, it was not like our modern medical system of scientific
analysis.
Early Amputation Tools
Shown here are the contents of a case of amputation instruments dating from about 1800.
Within medicine the most crucial component, besides the professional
Doctors,
Nurses and Pharmacologists are the drugs that make it possible for millions
of
humans everyday to overpower their ailments. Within the field of Medicine,
Pharmacology is the study and methodology behind the actions of drugs and
their reactions in the human body. Many early treatments didn't actually
heal
the patient, but just gave him a slight euphoria from the pain.
(Pg 1)
In today's culture, the medicines of our ancestors are now considered to be harmful to
oneself and are classified as illegal such as the drugs of marijuana and opium which
were
key in the Chinese, and Native American medical system. The origin of drugs vary from
common plants, (Aspirin, Digitalis, Ergot, Opium, Quinine, Reserpine) to minerals,
(Boric
Acid, Epsom Salts, Iodine) or synthetic compounds. The difference in a drug from being
helpful to being deadly is all in the dosage, which is determined by the amount of the
drug
that is found in the blood, this process is known as Serum Monitoring. The
risk-to-benefit
ratio of drug use is also extremely important, a drug could totally help one ailment but
in
turn cause another such as the drug niridazole, which helps schistosomaisis but is known
to
cause cancer. Even the national government has some control over the regulation of drug
use. Proprietary drugs are sold over the counter and promote less addiction that
Ethical
drugs which can only be obtained legally by a written prescription by a registered
doctor.
Jurisdiction of illegal drugs which produce a strong addiction is given to the Drug
Enforcement Administration of the U.S. Department of Justice. The most important
article
about doctor prescribed drugs is that the doctor is aware about other drugs in which
the
patient is taking, because one drug alone may be helpful but administered with another
could cause adverse side effects preventing recovery for the patient.
(Pg 2)
ASPIRIN
1"Acetylsalicylic acid, commonly known as aspirin is one of the most widely used
analgesics
in the world". Used by Ancient Greeks and Native Americans it was used to reduce fever
and
pain and could also be used as an anti-inflammatory agent. It interferes with tissue
contractions of the prostaglandin's which are chemicals involved in the production of
inflammation and pain. It modifies the temperature-regulating portion of the brain,
dilating blood vessels in the skin and increases sweating which in turn cools the body
reducing fever.
Aspirin also prevents the production of thromboxane which plays a key role in
coagulation
cascade, which slows blood clotting and is helpful in preventing heart attacks and
strokes.
It is derived from the bark of the willow tree, and its activity is produced from
chemicals
called salicylates.
(Pg 3)
2"Charles Gerhardt a French chemist first synthesized the acetyl derivative from the
salicylic acid in 1853 developing the first type of aspirin," but Felix Hoffman a
German
chemist was the first to realize its medical value in 1893. Over a long period of
constant
use aspirin can cause iron deficiency, gastric ulcers, kidney damage and if given to
children having chicken pox or influenza could cause the risk of contracting the fatal
brain disease known as Reye's syndrome.
Usage of Aspirin varies. Short term use of about 3"6-10 days" is recommended without
physician supervision but long term use requires periodic evaluations and dosage
restrictions.
(Pg 4)
Side effects also vary with the individual, they could include mild drowsiness,
allergic
reactions, skin rash, hives, nasal discharge, stomach irritation, heart burn, nausea,
vomiting, constipation and in extreme cases erosion of the stomach lining, activation of
a
peptic ulcer, bone marrow depression, hepatitis, and kidney damage. Overdosing on this
drug
produces side effects such as stomach distress, nausea, vomiting, ringing in the ears,
sweating, stupor, deep and rapid breathing, twitching, and convolutions.
Aspirin was the first non-steroidal anti-inflammatory drug (NASID) but by far not the
last. 4"One and a half million Americans suffer from heart attacks each year and about
200,000 suffer from heart related deaths". Aspirin helps millions of people each year
because it prevents premature blood clotting. No other NSAID can compare with the price
or
efficacy of aspirin but ibuprofen can come very close. Where aspirin might take up to
12
doses to relieve pain over a long period a strong dosage of ibuprofen could help the
patient in one dose.
Even though Ibuprofen works as well as aspirin care must be taken with its usage,
although
it does not irritate the stomach as much as aspirin it accelerates the damaging of the
kidneys. Another problem between aspirin and ibuprofen is price. 5"A 30 day supply of
aspirin could cost $3.95 where a 30 day supply of ibuprofen could cost $22.95".
(Pg 5)
New studies prove that aspirin also has effect over migraine headaches, cataracts,
gallstones, diabetic eye problems, insomnia, weight loss for women, wheat intolerance,
leprosy and even hip replacement complications. Aspirin plays an important role in
keeping
our bodies resistant against various illnesses and helping in times of injury.
(Pg 6)
SULFA DRUGS
Sulfonamides, the chemical name for sulfa drugs were the first chemical compounds to
provide safe and effective treatment to most common bacterial infections. Before the use
of
penicillin after the mid 1940's, Sulfa drugs played a major role in antibacterial
treatment
which resulted in a sharp decrease in deaths due to such bacterial infections. In
today's
modern medical system sulfa drugs are used to treat patients of urinary tract
infections.
Sulfur
Sulfur in its natural form is a tasteless, odorless, light yellow solid, once forcefully
fed
to children in the belief that it was good for their health. Sulfur compounds, found in
dairy products and eggs, are an essential dietary ingredient.
Instead of killing bacteria sulfa drugs prevent them from multiplying, making it easier
for
the bodies natural defenses to overcome and destroy them. Bacteria require certain
chemicals know as 6"para-aminobenzoic acids" to multiply, sulfa drugs resemble the
chemical
structure of the acids and can be absorbed by the bacteria. The sulfa drugs combine
with
the outer shells of the bacteria therefore not allowing the real acids to penetrate.
(Pg 7)
All bacteria are not reactant to sulfonamides and have to be screened by the physician
to
see if it is necessary to take a more serious action. Sulfa drugs can be taken orally
which
is most common, or by an injection just beneath the skin. In former medical history
they
were used to treat pneumonia, dysentery, blood poising, cellulitis, bubonic plague,
and
conjunctivitis.
Since the recognition of penicillin as an effective bacterial assailant and some
bacteria
becoming resistant to sulfonamides physicians have been less likely to prescribe them
since
the late 1940's. The combination of sulfamethoxazole and trimethoprim have given a new
usage for sulfa drugs, now they can be used for such ailments as middle ear infections,
shigellosis and recurring urinary tract infections.
(Pg 8)
7"Paul Gelmo in 1908 discovered the first sulfa drug" accidentally while looking for
dies
to better color woolen clothing unaware its future lye in the medical profession. In
8"1953
a German pathologist named Gerhard Domagk" reported that this dye killed streptococcal
bacteria in mice leading to the first research in to the bacteria fighting drug.
Major problems included with the first line of the drug sulfanilamide were included in
the
administration of the drug. It sometimes crystallized in the urine of the patient
causing
kidney damage. Later development of water soluble sulfa drugs solved the problem of
crystallization in the urine and gave the hope of a longer life span to people living
in
the 1930's.
(Pg 9)
(Pg 10)
ANTIBIOTICS
In the ancient language of Greek the term antibiotic meant 8oagainst lifeo. They are
chemical substances produced by one organism that in turn are destructive to another.
This
process traditionally has been called antibiosis and is the opposite of symbiosis. An
antibiotic is a type of chemotherapeutic agent, it has a toxic effect on certain types
of
disease-producing microorganisms without acting dangerously on the patient. Some
chemotherapeutic agents differ from antibiotics in that they are not secreted by
microorganisms, as are antibiotics, but rather are made synthetically in a chemical
laboratory. 9"Alternately examples are quinine, used against malaria; arsphenamine,
used
against syphilis; the sulfa drugs, used against a wide variety of diseases, notably
pneumonia; and the quinolones, used against hospital-derived infections (zoonoses)". A
few
antibiotics, among them penicillin and chloramphenicol, have now been produced
synthetically also. The first observation of what would now be called an antibiotic
effect
was made in the 10"19th century by the French chemist Louis Pasteur", who discovered
that
certain saprophytic bacteria can kill anthrax germs. Around the year 11"1900 the German
bacteriologist Rudolf von Emmerich isolated a substance called pyocyanase", which can
kill
the germs of cholera and diphtheria in the test tube. It was not useful, however, in
curing
disease. In the 12"1920s the British bacteriologist Sir Alexander Fleming, who later
discovered penicillin", found a substance called lysozyme in many of the secretions of
the
body such as tears and sweat, and in certain other plant and animal substances.
Lysozyme
has strong antimicrobial activity, but mainly against harmless bacteria.
(Pg 11)
(Sir Alexander Fleming)
Discovery of Penicillin
The research of Alexander Fleming in 1928 led to the discovery of penicillin, an
important
antibiotic derived from the mold Penicillin notatum. Penicillin is effective against a
wide
range of disease-causing bacteria. It acts by killing bacteria directly or by inhibiting
their growth.
Penicillin, the archetype of antibiotics was discovered by accident in 13"1928 by
Fleming",
who showed its effectiveness in laboratory cultures against many disease-producing
bacteria, such as those that cause gonorrhea and certain types of meningitis and
bacteria
(blood poisoning); however, he performed no experiments on animals or humans.
Penicillin
was first used on humans by the British scientists 14"Sir Howard Florey and Earnest
Chain
during the 1940-41 winter".
(Pg 12)
The first antibiotic to be used in the treatment of human diseases was tyrothricin (one
of
the purified forms of which was called gramicidin), which was isolated from certain
soil
bacteria by the American bacteriologist 15"RenT Dubos in 1939". This substance was too
toxic for general use, but it is employed in the external treatment of certain
infections.
Other antibiotics produced by actinomycetes, filamentous and branching bacteria,
occurring
in soil have proved more successful. One of these, streptomycin, discovered in 15"1944
by
the American microbiologist Selman Waksman and his associates", is effective against
many
diseases, including several in which penicillin is useless, especially tuberculosis.
Since
then, such antibiotics as chloramphenicol, the tetracyclines, erythromycin, neomycin,
nystatin, amphotericin, cephalosporins, and kanamycin have been developed and may be
used
in the treatment of infections caused by some bacteria, fungi, viruses, rickettsia, and
other microorganisms. In clinical treatment of infections, the causative organism must
be
identified and the antibiotics to which it is sensitive must be determined in order to
select an antibiotic with the greatest probability of killing the infecting organism.
Recently, strains of bacteria have arisen that are resistant to commonly used
antibiotics;
for example, gonorrhea-causing bacteria that high doses of penicillin are not able to
destroy may transfer this resistance to other bacteria by exchange of genetic
structures
called plasmids. Some bacteria have become simultaneously resistant to two or more
antibiotics by this mechanism. New antibiotics that circumvent this problem, such as
the
quinolones, are being developed.
(Pg 13)
The cephalosporins, for instance, kill many of the same organisms that penicillin does,
but
they also kill strains of those bacteria that have become resistant to penicillin. Often
the
resistant organisms arise in hospitals, where antibiotics are used most often, especially
to
prevent infections from surgery.
Another problem in hospitals is that many old and very ill patients develop infections
from
organisms that are not pathogenic in healthy persons, such as the common intestinal
bacterium Escherichia coli. New antibiotics have been synthesized to combat these
organisms. Fungus infections have also become more common with the increasing use of
chemotherapeutic agents to fight cancer, and more effective antifungal drugs are being
sought. The search for new antibiotics continues in general, as researchers examine
soil
molds for possible agents. Among those found in the 16"1980s, for example, are the
monobactams", which may also prove useful against hospital infections. Antibiotics are
found in other sources as well, such as the family of magainins 17"discovered in the
late
1980s in frogs; although untested in humans as yet, they hold broad possibilities".
Antibiotics have also been used effectively to foster growth in animals. Concern has
arisen, however, that this widespread use of antibiotics in animal feed can foster the
emergence of antibiotic-resistant organisms that may then be transmitted to human
beings.
(Pg 14)
ANTIHISTAMINES
Antihistamines are drugs that block the action of histamine. Histamine, also known as
histamine phosphate, an amine (beta-imidazolyl-ethylamine, ergamine, or ergotidime) that
is
a normal constituent of almost all animal body cells. Histamine is also found in small
quantities in ergot and purified meat products and is produced synthetically for
medicinal
purposes. In the body, it is synthesized in a type of leukocyte called a basophil or
mast
cell. In response to certain stimuli these cells release histamine, which immediately
effects a dilation of the blood vessels. This dilation is accompanied by a lowering of
blood pressure and an increased permeability of the vessel walls, so that fluids escape
into the surrounding tissues. This reaction may result in a general depletion of
vascular
fluids, causing a condition known as histamine poisoning or histamine shock. Allergic
reactions in which histamine is released, resulting in the swelling of body tissue,
show
similarities to histamine poisoning; the two may be basically similar, and the two
conditions are treated similarly. The release of histamine might also be partly
responsible
for difficult breathing during an asthma attack. 18"In the 1930s the Italian
pharmacologist
Daniel Bovet who live in 1907-1972, working at the Pasteur Institute in Paris",
discovered
that certain chemicals counteracted the effects of histamine in guinea pigs. The first
antihistamines were too toxic for use on humans, but 19"by 1942 they had been modified
for
use in the treatment of allergies". More than 25 antihistamine drugs are now available.
(Pg 15)
Histamine also causes contraction of involuntary muscles, especially of the genital
tract
and gastrointestinal canal, with an accompanying secretion by associated glands.
Because
histamine stimulates the flow of gastric juices, it is used diagnostically in patients
with
gastric disturbances. One drug effective in treating gastric ulcers acts by
antagonizing
the action of histamine. The ability of the body to localize infections may be due to
the
secretion of histamine and the subsequent increased local blood supply and increased
permeability of the blood vessels. Antihistamines are used primarily to control symptoms
of
allergic conditions such as hay fever. They alleviate runny nose and sneezing and to a
lesser extent, minimize conjunctivitis and breathing difficulties. Antihistamines can
also
alleviate itching and rash caused by food allergy. Chemically, antihistamines comprise
several classes and a person who does not obtain relief from one type may benefit from
another. Side effects of these drugs can include drowsiness, loss of concentration, and
dizziness. People taking antihistamines should not drink alcoholic beverages or perform
tasks requiring mental alertness, such as driving. A few antihistamines, such as
terfenadine and astemizole, are nonsedating. Although antihistamines are included in
many
over-the-counter cold remedies, their usefulness in such preparations is questionable.
(Pg 16)
Antihistamines may relieve symptoms of allergy accompanying a cold, or they may have an
anticholinergic effect that dries cold secretions, but they do not have any influence
on
viral infections, which are the cause of colds . Moreover, the drying effect may be
undesirable, especially for persons with bronchial infection, glaucoma, or urinary
tract
difficulties. Although there are not many alternate drugs that have the same properties
as
antihistamines some non-drug treatments are also effective against allergies. The use
of
High-Efficiency-Particulate-Arresting (HEPA) filters, eliminate microscopic particles
which
cause allergies. The use of mattress covers decrease the reaction to dust mites in the
mattress itself. These treatments are not equivalent to drug use but could decrease the
amount of allergenic agents in the house hold air. Vitamin C also plays a role in the
elimination of allergic reactions. 20"Researchers at the University of California have
found that patients that suffer from atopic dermatitis benefited from large dosages of
vitamin C".
(Pg 17)
THE HISTORY, USE AND EFFECTIVENESS OF
VITAMINS AND NUTRIENT SUPPLEMENTS
A Vitamin is any organic compound required by the body in small amounts for metabolism,
to
protect health, and for proper growth in children. Vitamins also assist in the formation
of
hormones, blood cells, the chemicals of the nervous-system, and genetic material. The
various vitamins are not chemically related, and most differ in their physiological
actions. They generally act as catalysts, combining with proteins to create
metabolically
active enzymes that in turn produce hundreds of important chemical reactions throughout
the
body. Without vitamins, many of these reactions would slow down or stop. The intricate
ways
in which vitamins act on the body, however, are still far from clear. The 13
well-identified vitamins are classified according to their ability to be absorbed in fat
or
water. The fat-soluble vitamins A, D, E, and K are generally consumed along with
fat-containing foods, and because they can be stored in the body's fat, they do not have
to
be consumed every day. The water-soluble vitamins, the eight B vitamins and vitamin C,
cannot be stored and must be consumed frequently, preferably every day. The body can
manufacture only vitamin D, all others must be derived from the diet. Lack of them
causes a
wide range of metabolic and other dysfunction's. In 21"the U.S., since 1940, the Food
and
Nutrition Board of the National Research Council has published recommended dietary
allowances for vitamins, minerals, and other nutrients". Expressed in milligrams or
international units for adults and children of normal health, these recommendations are
useful guidelines not only for professionals in nutrition
(Pg 18)
but also for the growing number of families and individuals who eat irregular meals and
rely
on prepared foods, many of which are now required to carry nutritional labeling.
A well-balanced diet contains all the necessary vitamins, and most individuals who
follow
such a diet can correct any previous vitamin deficiencies. However, persons who are on
special diets, who are suffering from intestinal disorders that prevent normal
absorption
of nutrients, or who are pregnant or lactating may need particular vitamin supplements
to
bolster their metabolism. Beyond such real needs, vitamin supplements are also often
believed to offer ocureso for many diseases, from colds to cancer; but in fact the body
quickly eliminates most of these preparations without absorbing them. In addition, the
fat-soluble vitamins can block the effect of other vitamins and even cause severe
poisoning
when taken in excess. Vitamin A is a pale yellow primary alcohol derived from carotene.
It
affects the formation and maintenance of skin, mucous membranes, bones, and teeth,
vision,
and reproduction. An early deficiency symptom is night blindness which is the difficulty
in
adapting to darkness. Other symptoms are excessive skin dryness, lack of mucous
membrane
secretion, causing susceptibility to bacterial invasion, and dryness of the eyes due to
a
malfunctioning of the tear glands, a major cause of blindness in children in developing
countries. The body obtains vitamin A in two ways. One is by manufacturing it from
carotene, a vitamin precursor found in such vegetables as carrots, broccoli, squash,
spinach, kale, and sweet potatoes. The other is by absorbing ready-made vitamin A from
plant-eating organisms. In animal form, vitamin A
(Pg 19)
is found in milk, butter, cheese, egg yolk, liver, and fish-liver oil. Although one-third
of
American children are believed to consume less than the recommended allowance of vitamin
A,
sufficient amounts can be obtained in a normally balanced diet rather than through
supplements. Excess vitamin A can interfere with growth, stop menstruation, damage red
blood
corpuscles, and cause skin rashes, headaches, nausea, and jaundice. Known also as vitamin
B
complex, these are fragile, water-soluble substances, several of which are particularly
important to carbohydrate metabolism.
Thiamine, or vitamin B1, a colorless, crystalline substance, acts as a catalyst in
carbohydrate metabolism, enabling pyruvic acid to be absorbed and carbohydrates to
release
their energy. Thiamine also plays a role in the synthesis of nerve-regulating
substances.
Deficiency in thiamine causes beriberi, which is characterized by muscular weakness,
swelling of the heart, and leg cramps and may, in severe cases, lead to heart failure
and
death. Many foods contain thiamine, but few supply it in concentrated amounts. Foods
richest in thiamine are pork, organ meats such as liver, heart, and kidney, brewer's
yeast,
lean meats, eggs, leafy green vegetables, whole or enriched cereals, wheat germ,
berries,
nuts, and legumes. Milling of cereal removes those portions of the grain richest in
thiamine; consequently, white flour and polished white rice may be lacking in the
vitamin.
Widespread enrichment of flour and cereal products has largely eliminated the risk of
thiamine deficiency, although it still occurs today in nutritionally deficient
alcoholics.
Riboflavin, or vitamin B2, like thiamine, serves as a coenzyme, one that must combine
with
a portion of another enzyme to be effective, in the metabolism of carbohydrates, fats,
and,
especially, respiratory proteins. It
(Pg 20)
also serves in the maintenance of mucous membranes. Riboflavin deficiency may be
complicated
by a deficiency of other B vitamins; its symptoms, which are not as definite as those of
a
lack of thiamine, are skin lesions, especially around the nose and lips, and sensitivity
to
light. The best sources of riboflavin are liver, milk, meat, dark green vegetables,
whole
grain and enriched cereals, pasta, bread, and mushrooms.
Niacin, or vitamin B3, also works as a coenzyme in the release of energy from nutrients.
A
deficiency of niacin causes pellagra, the first symptom of which is a sunburnlike
eruption
that breaks out where the skin is exposed to sunlight. Later symptoms are a red and
swollen
tongue, diarrhea, mental confusion, irritability, and, when the central nervous system
is
affected, depression and mental disturbances. The best sources of niacin are liver,
poultry, meat, canned tuna and salmon, whole grain and enriched cereals, dried beans
and
peas, and nuts. The body also makes niacin from the amino acid tryptophan. Megadoses of
niacin have been used experimentally in the treatment of schizophrenia, although no
experimental proof has been produced to show its efficacy. In large amounts it reduces
levels of cholesterol in the blood, and it has been used extensively in preventing and
treating arteriosclerosis. Large doses over long periods cause liver damage. Pyridoxine,
or
vitamin B6, is necessary for the absorption and metabolism of amino acids. It also
plays
roles in the use of fats in the body and in the formation of red blood cells.
Pyridoxine
deficiency is characterized by skin disorders, cracks at the mouth corners, smooth
tongue,
convulsions, dizziness, nausea, anemia, and kidney stones. The best sources of
pyridoxine
are whole (but not enriched) grains, cereals, bread, liver, avocados, spinach, green
beans,
and bananas.
(Pg 21)
Pyridoxine is needed in proportion to the amount of protein that is consumed.
Cobalamin, or vitamin B12, one of the most recently isolated vitamins, is necessary in
minute amounts for the formation of nucleoproteins, proteins, and red blood cells, and
for
the functioning of the nervous system. Cobalamin deficiency is often due to the
inability
of the stomach to produce glycoprotein, which aids in the absorption of this vitamin.
Pernicious anemia results, with its characteristic symptoms of ineffective production
of
red blood cells, faulty myelin (nerve sheath) synthesis, and loss of epithelium the
membrane lining of the intestinal tract. Cobalamin is obtained only from animal sources
such as liver, kidneys, meat, fish, eggs, and milk. Vegetarians are advised to take
vitamin
B12 supplements. Folic acid, or folacin, is a coenzyme needed for forming body protein
and
hemoglobin; its deficiency in humans is rare. Folic acid is effective in the treatment
of
certain anemias and sprue. Dietary sources are organ meats, leafy green vegetables,
legumes, nuts, whole grains, and brewer's yeast. Folic acid is lost in foods stored at
room
temperature and during cooking. Unlike other water-soluble vitamins, folic acid is
stored
in the liver and need not be consumed daily. Pantothenic acid, another B vitamin, plays
a
still-undefined role in the metabolism of proteins, carbohydrates, and fats. It is
abundant
in many foods and is manufactured by intestinal bacteria as well. Biotin, a B vitamin
that
is also synthesized by intestinal bacteria and widespread in foods, plays a role in the
formation of fatty acids and the release of energy from carbohydrates. Its deficiency
in
humans is unknown.
This well-known vitamin is important in the formation and maintenance of collagen, the
protein that supports many body structures and plays a major
(Pg 22)
role in the formation of bones and teeth. It also enhances the absorption of iron from
foods
of vegetable origin. Scurvy is the classic manifestation of severe ascorbic acid
deficiency.
Its symptoms are due to loss of the cementing action of collagen and include
hemorrhages,
loosening of teeth, and cellular changes in the long bones of children. Assertions that
massive doses of ascorbic acid prevent colds and influenza have not been borne out by
carefully controlled experiments. In other experiments, however, ascorbic acid has been
shown to prevent the formation of nitrosamines which are compounds found to produce
tumors
in laboratory animals and possibly also in humans. Although unused ascorbic acid is
quickly
excreted in the urine, large and prolonged doses can result in the formation of bladder
and
kidney stones, interference with the effects of blood-thinning drugs, destruction of
B12,
and the loss of calcium from bones. Sources of vitamin C include citrus fruits, fresh
strawberries, cantaloupe, pineapple, and guava. Good vegetable sources are broccoli,
Brussels sprouts, tomatoes, spinach, kale, green peppers, cabbage, and turnips.
This vitamin is necessary for normal bone formation and for retention of calcium and
phosphorus in the body. It also protects the teeth and bones against the effects of low
calcium intake by making more effective use of calcium and phosphorus. Also called the
sunshine vitamin, vitamin D is obtained from egg yolk, liver, tuna, and vitamin-D
fortified
milk. It is also manufactured in the body when sterols, which are commonly found in
many
foods, migrate to the skin and become irradiated. Vitamin D deficiency, or rickets,
occurs
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