Cranberry
Excellent source of anthocyanidins, pycnogenol-like substances. Cranberry is
legendary for cleansing and prevention of infections of the urinary tract.
Blocks damaging effects of some toxins.
5.5% Anthocyanidins, Vitamins, minerals & enzymatic pigments.
Cranberry Compounds Fight Urinary Tract Infection
Drinking cranberry juice is a common home remedy for a urinary tract infection,
but just how it works was not understood.
A group of researchers believe they have found the answer: The effect is due
not to the highly acidic nature of cranberries but to specific compounds in
cranberries that inhibit the adherence of Escherichia coli (bacteria) to
uroepithelial cells.
Escherichia coli, or E. coli, is a bacterium found normally in the digestive
tract. However, if certain strains of the bacteria gain access to the normally
sterile environment of the bladder and urinary tract, the bacteria can trigger
an infection, with symptoms including a frequent, painful urge to urinate and
blood in the urine. The condition can be readily treated with antibiotics, but
recurs in about 60% of cases.
In a new study, the researchers tested the ability of cranberry extracts to
inhibit the binding of certain, disease-causing strains of E. coli to cells
taken from the lining of the urinary tract which would promote flushing of
bacteria from the bladder into the urine stream, resulting in the prevention or
reduction of symptoms.
This binding process is thought to be an early step in the initiation of an
infection. During the course of the 5-year study, the team found that extracts
containing compounds called "condensed tannins" or "proanthocyanidins,"
which are found in cranberries and blueberries, could inhibit the binding process.
The New England Journal of Medicine October 8, 1998; 339:1085-1086.
The majority of physicians and other health professionals believe there is a
clear association between a diet high in fruits and vegetables and a low risk of
chronic disease. Phytonutrients (naturally derived plant compounds),
particularly antioxidants, are increasingly being shown to help optimize human
health.
Cranberries contain proanthocyanidins (PACs) that can prevent the adhesion of
certain of bacteria, including E. coli, associated with urinary tract infections
to the urinary tact wall. The anti-adhesion properties of cranberry may also
inhibit the bacteria associated with gum disease and stomach ulcers.
Recent scientific research shows that cranberries and cranberry products
contain significant amounts of antioxidants and other phytonutrients that may
help protect against heart disease, cancer and other diseases.
Antioxidants
Cranberries have been shown to contain more antioxidant phenols than 19 commonly
eaten fruits according to a study published in the November 19, 2001 edition of the
Journal of Agriculture and Food Chemistry. "These antioxidants may play a
role in helping to prevent heart disease and certain cancers" according to the
study's author Dr. Joe Vinson at the University of Scranton,
Pennsylvania. Antioxidants are naturally manufactured by the body and/or are
ingested primarily as components of fruits and vegetables. Cranberries can serve
as a good source of supplemental antioxidants.
Bacterial Anti-adhesion and Antibiotic Resistance
Evidence indicates that natural components in cranberries act to inhibit the
adhesion of infection-causing E. coli bacteria within the urinary tract. The compounds
responsible have been identified by Howell et al. as proanthocyanidins (PACs),
or condensed tannins. While many fruits contain similar compounds, thus far only
the PACs of cranberries and blueberries, which are botanically related species,
have been shown to exhibit this effect. More detailed work presented in April
2002 showed that of tests with cranberries, grapes, apples, tea, and chocolate,
only cranberries exhibited this ability to block bacteria from sticking.
While cranberry is perhaps
best known for its effect on urinary tract health, newer research indicates that
it may act elsewhere in the body against other bacteria as well. The adhesion of
the different types of bacteria that cause both stomach ulcers, and periodontal
gum disease, have been shown to be inhibited in the presence of cranberry, and
it is likely that others susceptible bacteria will be found as well.
It is likely that the anti-adhesion effect may have far reaching implications.
Not only may regular consumption of cranberry products help maintain health, but
in the process will reduce the number of infections in a given population, and
thereby the doses of antibiotics which are needed. It is becoming increasingly
clear that a reduction in general antibiotic use also reduces the likelihood of
the bacteria becoming resistant to those very same antibiotics, which is a public
health problem of global proportions.
Heart Disease
Flavonoids have been shown to function as potent antioxidants both in vitro and
in vivo and may reduce the risk of atherosclerosis. Cranberries contain significant
amounts of flavonoids and polyphenolic compounds that have been demonstrated to inhibit
low density lipoprotein oxidation. Ongoing research continues to suggest that cranberries
may offer a natural defense against atherosclerosis. Atherosclerosis, in the
simplest terms, is the accumulation of low density lipoprotein (LDL), or "bad
cholesterol", in arteries resulting in restricted blood flow. In advanced stages
of the disease, blood flow may decrease severely or cease completely, resulting
in angina (chest pain), a thrombosis (blood clot) and/or myocardial infarction
(heart attack). Atherosclerosis is a primary cause of cardiovascular disease.
Health Benefits
Protection against Urinary Tract Infection
Cranberries have been valued for their ability to reduce the risk of urinary
tract infections for hundreds of years. In 1994, a placebo-controlled study of
153 elderly women was published in the Journal of the American Medical
Association that gave scientific credibility to claims of cranberries
effectiveness in preventing urinary tract infection. In this study, the women
given cranberry juice had less than half the number of urinary infections as the
control group (only 42% as many, to be precise), who received a placebo
imitation ?cranberry? drink. The daily dose of cranberry juice in this initial
study was just 300 milliliters (about one and one-quarter cups). Since then, a
number of other studies have also confirmed anecdotal tales of cranberry?s
ability to both treat and prevent urinary tract infections. In most of these
later studies, subjects drank about 16 ounces (2 cups) of cranberry juice daily.
How does cranberry juice help prevent urinary tract infections? It acidifies
the urine, contains an antibacterial agent called hippuric acid, and also
contains other compounds that reduce the ability of E. coli bacteria to adhere
to the walls of the urinary tract. Before an infection can start, a pathogen
must first latch on to and then penetrate the mucosal surface of the urinary
tract walls, but cranberries prevent such adherence, so the E. coli is washed
away in the urine and voided. Since E. coli is pathogen responsible for 80-90%
of urinary tract infections, the protection afforded by cranberries is quite
significant. The most recent studies attempting to explain cranberries?
protective effects on urinary tract health were presented at the Experimental
Biology Conference held in April 2002. Amy Howell, research scientist at the
Marucci Center for Blueberry Cranberry Research at Rutgers University and Jess
Reed, professor of nutrition at the University of Wisconsin-Madison, compared
the proanthycyanins (active compounds) in cranberries to those found in grapes,
apples, green tea and chocolate. They discovered that ?the cranberry's
proanthocyanidins are structurally different than the proanthocyanidins found in
the other plant foods tested, which may explain why cranberry has unique
bacterial anti-adhesion activity and helps to maintain urinary tract health.?
8-Ounces Better than 4 to Prevent Bladder Infections
Cranberry's protective effects against bladder infections may be dose
responsive, with 8-ounces of cranberry juice being twice as effective as
4-ounces, suggests preliminary research presented at the 42nd Annual Meeting of
the Infectious Diseases Society of America by Kalpana Gupta from the University
of Washington.
Gupta reported the details of a very small trial in which three volunteers
were given 27% cranberry juice cocktail. Urine samples, collected before and 4-6
hours after drinking the cranberry juice, were combined with human bladder cells
and incubated with Escherichia coli (the most common cause of bladder
infections). The number of bacteria able to adhere to the bladder cells (the
first step a pathogen must achieve to be able to cause infection) was
significantly reduced in the urine of all women who drank the cranberry juice
cocktail, and the effect was doubled when the women drank eight ounces of
cranberry rather than four ounces. Cranberry's protective effect is thought to
be due to a specific type of tannin, found only in cranberries and blueberries,
which interferes with projections on the bacterium, preventing it from sticking
to the walls of the bladder and causing infection. However, once the bacteria
have established a hold, it's best to seek medical advice. No evidence shows
cranberry juice is able to cure an established bladder infection, which can lead
to a more serious kidney infection. The researchers plan further studies in a
larger group of women to investigate the optimal amount and frequency of
cranberry juice consumption.(December 17, 2004)
Cranberries Combat Genital Herpes
Laboratory studies published in the October 2004 issue of the Journal of
Science, Food and Agriculture have shown that a phytonutrient isolated from
cranberries is effective against the herpes simplex virus (HSV-2), the cause of
genital herpes. In a manner similar to the way the tannins in cranberries
protect against bladder infection by preventing bacteria from adhering to the
bladder wall, cranberries' antiviral compound, proanthocyanidin A-1, inhibits
the attachment and penetration of the herpes virus. (december 17, 2004)
A Pro-biotic Berry for Gastrointestinal and Oral Health?
Not only kidney infections, but the majority of infectious diseases are
initiated by the adhesion of pathogenic organisms to the tissues of the host.
Cranberries ability to block this adhesion has been demonstrated not only
against E. coli, the bacterium most commonly responsible for urinary tract
infection, but also for a number of other common pathogens.
Delegates at the 2002 American Chemical Society meeting and Experimental
Biology Conference were also informed about cranberries? ability to act as a
natural probiotic, supporting the health-promoting bacteria that grow in the
human gastro-intestinal tract while killing off the bacteria that promote
infections and foodborne illnesses.
One study presented by Leslie Plhak from the University of Wisconsin-Madison
found that whole frozen cranberries contained compounds able to inhibit the
growth of common foodborne pathogens including Listeria monocytogenes and E.
coli 0157:H7, but enhanced the growth of the beneficial bacterium Lactobacillus
fermentum by as much as 25 times.
Another test tube study published in Critical Reviews in Food Science and
Nutrition in 2002 indicated that a constituent in cranberry juice prevents the
bacterium responsible for most gastric ulcers, Helicobacter pylori, from
adhering to gastric epithelial cells (the cells that form the lining of the stomach).
Also published in this same journal in 2002 was a study noting that compounds
isolated from cranberry juice actually dissolved the aggregates formed by many
oral bacteria and was effective in decreasing the salivary level of Streptococus
mutans, the major cause of tooth decay. Among the other fruits tested, none had
a similar effect except blueberries, whose protective action was much weaker
that that of cranberries.
Prevention of Kidney Stone Formation
Cranberries contain quinic acid, an acidic compound that is unusual in that
it is not broken down in the body but is excreted unchanged in the urine. The
presence of quinic acid causes the urine to become just slightly acidic?a level
of acidity that is, however, sufficient to prevent calcium and phosphate ions
from joining to form insoluble stones. In patients who have had recurrent kidney
stones, cranberry juice has been shown to reduce the amount of ionized calcium
in their urine by more than 50%?a highly protective effect since in the U.S.,
75-85% of kidney stones are composed of calcium salts.
In one recent study evaluating the effect of cranberry juice on kidney stone
formation, study subjects were divided into two groups, one of which drank 2
cups of cranberry juice diluted with 6 cups water each day for 2 weeks, while
the other group drank tap water for the same period. After a 2 week period in
which neither group drank any cranberry juice, the groups were switched, so that
those who had drunk cranberry juice drank only tap water, while those who had
drunk tap water consumed 2 cups cranberry juice diluted with 6 cups tap water
daily for an additional 2 weeks. In both groups, drinking cranberry juice was
found to significantly and uniquely alter three key urinary risk factors for the
better: oxalate and phosphate excretion decreased; citrate excretion increased;
and the relative supersaturation of calcium oxalate was significantly lower.
In another trial that evaluated the influence of cranberry, plum and
blackcurrant juice on urinary stone risk factors, cranberry juice decreased the
urinary pH (made the urine more acidic), and increased the excretion of oxalic
acid and the relative supersaturation for uric acid. The researchers concluded
that cranberry juice could be useful in the treatment of brushite (calcium) and
struvite (non-calcium) stones as well as urinary tract infection.
Cholesterol-Lowering
After test tube research conducted at the University of Scranton demonstrated
that cranberries? antioxidants could protect LDL cholesterol from oxidation, and
animal research at three other universities provided evidence that cranberries
can decrease levels of total cholesterol and LDL (low density or ?bad?
cholesterol), a human study has also corroborated these positive results.
The three month study funded by the U.S. Cranberry Institute was presented in
March of 2003 at the 225th national meeting of the American Chemical Society.
Researchers measured cholesterol levels in 19 subjects with high cholesterol
after a fasting, baseline blood sampling, followed by monthly samplings. Ten of
the subjects were given cranberry juice with artificial sweetener, while the
other subjects drank cranberry juice with no added sugars. Like typical
supermarket cranberry juices, the drinks all contained approximately 27% pure
cranberry juice by volume. Each subject drank one 8-ounce glass of juice a day
for the first month, then two glasses a day for the next month, and finally,
three glasses a day during the third month of the study. Subjects were not
monitored with respect to exercise, diet and alcohol consumption.
Although no changes occurred in their overall cholesterol levels, study
subjects? HDL (good) cholesterol increased by an average of 10% after drinking
three glasses of cranberry juice per day?an increase that, based on known
epidemiological data on heart disease, corresponds to approximately a 40%
reduction in heart disease risk.
Similarly, subjects? plasma antioxidant capacity, a measure of the total
amount of antioxidants available in the body, was significantly increased?by as
much as 121% after two or three servings of juice per day. Increased antioxidant
levels are also associated with a decreased risk of heart disease.
While the mechanism by which cranberry juice changes cholesterol levels has
not been clearly established, the researchers have theorized that the effect is
due to the fruit's high levels of polyphenols, a type of potent antioxidant.
Antioxidant Protection
Studies conducted at the University of Scranton, PA, and funded by the
Cranberry Institute, a trade association for cranberry growers in the US and
Canada, have revealed cranberries to be phytochemical powerhouses packed with
five times the antioxidant content of broccoli. When compared to 19 other common
fruits, cranberries were found to contain the highest level of antioxidant phenols.
Other studies presented at the 223rd national meeting of the American
Chemical Society in April 2002 also showed that cranberries have among the
highest levels of phenols of commonly consumed fruits. One study presented at
the meetings by biochemist Yuegang Zuo from the University of
Massachusetts-Dartmouth looked at 20 different fruit juices and found that
cranberry juice had the most phenols and the highest radical scavenging capacity
of all of them.
The most recent study to compare levels of phenolic compounds in common
fruits, which was conducted at Cornell University and published in the December
2002 issue of the Journal of Agriculture and Food Chemistry also
confirmed that cranberries had the highest phenolic content of the fruits
studied. Cranberries were followed in descending order by apple, red grape,
strawberry, pineapple, banana, peach, lemon, orange, pear and grapefruit.
Cancer Prevention
Also at the April 2002 national meeting of the American Chemical Society,
Catherine Neto, assistant professor at the University of
Massachusetts-Dartmouth, presented research on several newly discovered
compounds in cranberries that were toxic to a variety of cancer tumor cell
lines, including lung, cervical, prostate, breast and leukemia cancer cells. The
Cornell study mentioned above that confirmed cranberries as having the highest
levels of antioxidants among common fruits also found that cranberries had the
strongest ability to inhibit the proliferation of human liver cancer cells.
For cancer prevention, enjoy whole cranberries, not just cranberry juice.
Cranberry presscake (the material remaining after squeezing juice from the
berries), when fed to mice bearing human breast cancer cells, has previously
been shown to decrease the growth and metastasis of tumors. A new study
published in the June 2004 issue of the Journal of Nutrition suggests
compounds in whole cranberries also inhibit prostate, skin, lung and brain
cancer cells as well.
Androgen-dependent prostate cancer cells were inhibited the most (just 10 mg
of a warm water extract of cranberry presscake inhibited their growth by 50%).
With androgen-independent prostate cancer cells and estrogen-independent breast
cancer cells, a larger amount was needed but produced the same beneficial effect
(250 mg of cranberry presscake extract inhibited their growth by 50%).
Researchers concluded that the active compounds in whole cranberry prevent
cancer by blocking cell cycle progression and inducing cells to undergo
apoptosis (programmed cell death). (October 19, 2004)
Aiding in Recovery from Stroke
In laboratory studies using rat brain cells exposed to simulated stroke
conditions, a concentrated cranberry extract reduced the death of brain cells by
half in comparison to cells that did not receive the extract, scientists
reported in 2003 at the 226th meeting of the American Chemical Society. The
researchers, led by Professor Catherine Neto from the University of
Massachusetts-Dartmouth, believe their findings suggest that cranberry juice
could aid the recovery of stroke patients, particularly in the earliest stages,
when the most severe damage occurs. The researchers think that although
cranberry juice may not prevent a stroke from occurring initially, it may reduce
the severity of the stroke and thus the resulting symptoms. Neto was quoted as
saying that ?although both animal and human studies are needed to confirm these
initial findings, this study offers a compelling reason for recent stroke
victims and those at risk for stroke to consume cranberries.? Until those
studies are done, however, it is unclear what amount of cranberries or cranberry
juice people should eat or drink to have an optimal effect against stroke.
Protection against Macular Degeneration
Your mother may have told you carrots would keep your eyes bright as a child,
but as an adult, it looks like fruit is even more important for keeping your
sight. Data reported in a study published in the June 2004 issue of the
Archives of Ophthalmology indicates that eating 3 or more servings of fruit
per day may lower your risk of age-related macular degeneration (ARMD), the
primary cause of vision loss in older adults, by 36%, compared to persons who
consume less than 1.5 servings of fruit daily.
In this study, which involved 77,562 women and 40,866 men, researchers
evaluated the effect of study participants' consumption of fruits; vegetables;
the antioxidant vitamins A, C, and E; and carotenoids on the development of
early ARMD or neovascular ARM, a more severe form of the illness associated with
vision loss. Food intake information was collected periodically for up to 18
years for women and 12 years for men. While, surprisingly, intakes of
vegetables, antioxidant vitamins and carotenoids were not strongly related to
incidence of either form of ARM, fruit intake was definitely protective against
the severe form of this vision-destroying disease. Three servings of fruit may
sound like a lot to eat each day, but by simply tossing a banana into your
morning smoothie or slicing it over your cereal, topping off a cup of yogurt or
green salad with a half cup of cranberries,and snacking on an apple, plum,
nectarine or pear, you've reached this goal. (July 10, 2004)
Description
A glossy, scarlet red, very tart berry, the cranberry belongs to the same
genus as the blueberry, Vaccinium. Like blueberries, cranberries can still be
found growing as wild shrubs in northern Europe, northern Asia, and North
America. When cultivated, however, cranberries are grown on low trailing vines
atop great sandy bogs.
Cranberries have also been called ?bounceberries,? because ripe ones bounce,
and ?craneberries,? a poetic allusion to the fact that their pale pink blossoms
look a bit like the heads of the cranes that frequent cranberry bogs. The
variety cultivated commercially in the northern United States and southern
Canada, the American Cranberry, produces a larger berry than either the Southern
cranberry, a wild species that is native to the mountains of the eastern United
States, or the European variety.
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