| Nutritional
Support for Colds and Flu
by Jim English
Humans lived for millions of years without the
benefit of modern pharmaceutical antibiotics. Pharmaceutical antibiotics
were first introduced into medicine in the 1930's. Prior to that
time, physicians and their patients relied primarily on antimicrobial
substances like colloidal silver, antiseptics like alcohol and hydrogen
peroxide, and various plant extracts which stimulated the body's
own defense mechanisms. This latter approach—that of stimulating
the body's defenses—is rarely considered today in 'orthodox'
medicine. Although there are few immune-stimulating pharmaceutical
drugs available today, there are a number of immune-enhancing nutrients
and herbs that can dramatically energize a flagging immune system,
and help overcome an attack by bacteria and viruses.
Herbs have been used for centuries in virtually every culture in
the world. Native American medicine relied heavily on the use of
herbs, and traditional herbal remedies are still commonly prescribed
in Eastern countries such as China, Korea, and Japan as well as
Europe. Over time, trial and error led to the development of folk
medicines, with the most effective remedies being passed down through
the generations. Herbs have been used in an attempt to treat nearly
every known affliction and disease, with mixed results. While some
herbs have been shown to be ineffective, others have stood the tests
of time and research, proving their worth. The following examples
point out how nature has provided us with safe, effective methods
of improving our health and quality of life.
In traditional Chinese herbal medicine Astragalus is believed to
promote and enhance the immune system, replenish the 'defensive
energy' and accelerate wound healing. A. membranaceus , the form
of Astragalus used for medicinal purposes, is believed to enhance
immune function by altering the metabolism of immune cells. Studies
in both humans and laboratory animals have demonstrated a potent
antiviral potential via its ability to protect against infection
from the viruses that cause influenza and the common cold. Both
oral and nasal administration of Astragalus extracts have offered
protection against the common cold. In patients who are susceptible
to colds and flu, treatment with Astragalus for short periods of
time (two weeks) enhanced interferon induction by the white blood
cells, resulting in increased levels of cytokines (such as interleukin-2
and IgA and IgG).
Astragalus treatment leads to an increase in T-helper
cell activity. This increase in immune function was clearly demonstrated
in one study where immuno-deficient and healthy normal mice were
treated with Astragalus extract. This effect has been noted in humans
as well. When mononuclear cells from cancer patients and healthy
volunteers were inoculated with extracts of Astragalus, not only
did T cell levels rise to levels similar to that of healthy cells
(prior to treatment), T cell levels in cells from healthy individuals
were also significantly increased.
Echinacea, an herb native to North America, has played an important
role in Native American medicine. It was used by numerous tribes
to treat a variety of symptoms and diseases, including: sore mouth
and gums, toothache and coughs, and as an anti-inflammatory and
antiseptic agent.
More recently Echinacea has been closely examined
for its influence on immune cell proliferation, antibody production,
and antiviral activities. One of the most popular uses of Echinacea
is for support and recovery from the common cold and influenza.
Two recent studies support the use of Echinacea for this purpose.
In the first study, 108 patients with colds received
either Echinacea or a placebo for eight weeks. Of those patients
receiving the Echinacea, 35.2 percent recovered and remained healthy,
while only 25.9 percent of the placebo group remained healthy. When
patients did become infected, the length of time between infections
was 40 days for the Echinacea group vs. only 25 days for placebo.
When infection did occur in patients receiving Echinacea, the symptoms
were less severe and resolved quicker.
In a second study, 180 patients with influenza
were given either an E. purpurea Echinacea extract or a placebo.
The group receiving Echinacea showed significant reduction of cold
symptoms.
Cat's Claw ( Unicaria tomentosa ), a woody vine that grows in Peru,
is a traditional phytomedicine of the Ashaninka Indians. The Ashaninkas
drink a tea made of the bark once every week or two for general
health. In the event of an illness, they consume about a liter every
day until all symptoms have disappeared.
Both the root and the bark of Cat's Claw, a liana
growing to 100 feet or more, are sources of a rich variety of pharmacologically
active compounds. Among some of the compounds found in U. tomentosa
are catechins, alkaloids, ellagic acid and other phenolic antioxidants
which are beneficial in the treatment of specific types of cancer.
The most immunologically active alkaloids, the oxindole alkaloids,
isopteropodine and pteropodine, have been found by Dr. Klaus Keplinger,
an Austrian researcher, to stimulate immune function. In addition,
the presence of glycosides, proanthocyanidins and beta sitosterol
help provide anti-viral, anti-tumor and anti-inflammatory support
for the body.
Ginseng has been used for centuries in China, Japan, Korea, and
parts of the former Soviet Union for its supportive role in maintaining
health. As an adaptogen, Ginseng is believed to produce a state
of increased resistance to stress, supporting our ability to resist
disease by building up our general vitality and strengthening our
normal body functions.
Soviet researchers have been particularly keen
on ginseng and have claimed their studies show the herb and its
extracts can boost immunity, inhibit cancer, increase energy and
physical stamina and have variable effects on blood pressure and
blood sugar.
A recent study found that ginseng helps prevent
symptoms of the common cold and improves antibody response to influenza
vaccine. For 12 weeks, 227 volunteers who visited three private
medical practices in Milan received daily oral capsule doses of
either 100 mg of a standard Ginseng extract or a placebo. During
the fourth week they received an influenza vaccination. There were
only 15 cases of influenza or common cold in the group receiving
the ginseng extract, versus 42 cases in the group receiving the
placebo. By the eighth week, antibody titers rose to an average
272 units in the ginseng group, versus only 171 units in the placebo
group. Additionally, at both the eighth and twelfth weeks, natural
killer cell activity was nearly twice as high in the Ginseng group
versus the placebo group.
Recent studies have shown how antioxidants may play an important
role in the treatment of viral diseases. Antioxidants not only reduce
disease symptoms, but may also reduce the long-term effects of chronic
oxidative stress, which has been linked to the development of cancer
from some viral infections. Oxidative stress is seen in individuals
infected with influenza, immunodeficiency virus and hepatitis.
Vitamin C has seemingly been at the center of nutritional research,
particularly with regard to the common cold. It is well known that
vitamin C is a powerful antioxidant, and this protective activity
is now proving vital in recovery from infection. A number of studies
have found that, during infection, there is a marked decrease in
vitamin C levels in plasma and white blood cells. The concentration
of vitamin C in phagocytes and lymphocytes is over 10 times greater
than in plasma, and low intake of vitamin C has been shown to decrease
phagocytic activity in animal models.
Other studies have shown that higher vitamin C
concentration increases the proliferative responses of T lymphocytes
in vitro. Vitamin C has also been reported to induce the production
of interferon in cell culture, and one study has found a correlation
between natural killer cell activity and vitamin C concentration
in leukocytes. Under in vitro conditions, vitamin C has been found
to inactivate viruses and bacteria. In human studies doses higher
than 100 grams per day have been used for severe bacterial and viral
infections.
In a recent study, Italian researchers found that
two grams per day of ascorbic acid (vitamin C) was effective in
restoring bronchial responsiveness in hospital workers suffering
from upper respiratory infections. The authors suggest that ascorbic
acid can effectively re-establish the redux state in inflamed airways
and may prove beneficial for treatment of coughs during upper respiratory
infection.
Vitamin E, the body's premier fat-soluble antioxidant and complement
of vitamin C, is the major protective antioxidant for cell membranes.
Just as vitamin E protects serum lipoproteins and regulates prostaglandin
balance, new research suggests that vitamin E supplementation may
enhance phagocytosis, cell-mediated immunity, humoral immunity,
and reduce the effects of stress on the immune response.
In an animal study on heart disease in the elderly,
aged mice were fed vitamin E at 500 parts per million two months
before exposure to influenza. These animals were found to have substantially
lower amounts of the influenza virus in their lungs than control
mice given smaller amounts at 30 parts per million.
A related study on age and immune response involved
47 subjects, aged 61 to 79 years. Researchers reported that those
receiving a supplement containing vitamin E and other micronutrients
showed a significant increase in immune response. Specifically,
an increase in CD57 natural killer cells, T cells and T cell subsets.
Conversely, in the placebo group there was a decrease in T cells,
CD4 cells and the CD4:CD8 ratio. Researchers concluded that nutritional
intervention provided an effective approach for delaying the overall
decline in immune function noted with increasing age.
Glutathione is an intracellular thiol (sulfur-containing compound)
that acts as the body's principal antioxidant by providing intracellular
defense against oxidative stresses caused by free radicals, reactive
oxygen intermediates, and certain toxic chemicals. Glutathione aids
in the recycling and maintenance of tissue vitamin C and vitamin
E levels. Glutathione also works by detoxifying hydrogen peroxide
(H2O2) and other organoperoxidases (free radicals), and by protecting
against oxidation within cells via the Glutathione Redux Cycle.
This role as a free radical scavenger is primarily accomplished
through glutathione peroxidase (GSH px), which interacts to reduce
hydrogen peroxide to harmless water and thereby limit its capacity
to cause damage.
Whey Protein Concentrate (WPC) is a nutritional
supplement that increases intracellular production of glutathione
(GSH), to enhance the immune system. It has been theorized that
the ability of lymphocytes (CD4 cells) to correct oxidative damage
is determined by their capacity to regenerate intracellular stores
of glutathione, which allows them to respond vigorously to a wide
variety of antigens.
In 1981, researchers discovered that mice fed
a non-denatured whey protein concentrate exhibited a marked increase
in antibody production in response to T-cell dependent antigens.
Numerous experiments in subsequent years have confirmed this early
observation. Thus, enhanced immunity against colds and hepatitis,
and most dramatically, pneumococcal infection, could be accomplished
through dietary supplementation with whey protein concentrates (WPCs).
Vitamin A is one of the best documented nutrients for supporting
immune function. A deficiency in vitamin A is known to reduce resistance
to infection by lowering neutrophil phagocytosis, cell-mediated
immunity, humoral response and interleukin II production. Recent
research has found a strong link between vitamin A intake and upper
respiratory infections.
One 1996 study of newborn infants recorded substantial
decreases in upper respiratory infection in newborns given 50,000
IU of vitamin A versus a placebo. Researchers concluded that neonatal
vitamin A supplementation reduces infant mortality rates, as well
as lessens the severity of respiratory infection.
A second study linking vitamin A intake and respiratory
infection followed 28,000 children between six months and six years
of age. Higher intake of vitamin A was strongly associated with
fewer upper respiratory infections, lessened incidence of diarrhea
and a reduction in cough and fever. Of notice, there was a significant
positive association with vitamin A intake and the lowered incidence
of cough alone, a sign of a healthy respiratory epithelium.
N-Acetyl Cysteine (NAC) has been extensively researched for its
antioxidant properties, particularly in its potential to neutralize
the chemical by-products of smoking. NAC has been used for bronchial
congestion for over thirty years, and is used to fight chronic lung
diseases because of its ability to break up mucus. However, one
of the most exciting areas of NAC research is in the area of immunology.
NAC has been found to significantly enhance human T-cell function,
especially in older individuals. NAC is currently undergoing clinical
trials around the world as an augmenter of immune function in people
with AIDS. Its ease of conversion to both extracellular and intracellular
glutathione, coupled with its stability and long half-life in the
body, makes it an economical and powerful antioxidant.
Another powerful immune enhancer is Thymic Protein A, a protein
extracted from calf thymus which increases T-cells. T-cells are
types of white blood cells produced by the thymus gland which locate
and destroy foreign invaders. The thymus gland, which is located
behind the sternum (breast bone), shrinks as we age, resulting in
a decline in immune function. Thymic Protein A has shown in numerous
animal studies to dramatically improve immune function. Thymic Protein
A is safe and can even be used by children.
Olive leaf extract is a potent anti-viral, anti-bacterial and anti-fungal
supplement that has been shown to be effective at boosting the immune
response and aiding the body in defending against infections. Two
components of olive leaf extract, oleuropein and calcium elenolate
, have been shown to be particularly effective at inactivating the
viruses that cause colds and flu.
In the late 1960s researchers from the Upjohn
Company discovered that the components of olive leaf extract exhibited
powerful antibacterial and antiviral effects. Of special interest
was an antimicrobial fraction, calcium elenolate, that proved to
be lethal to every virus the researchers tested it against. Further
research demonstrated that other components of olive leaf extract
are toxic to a wide range of bacteria, protozoa, yeasts, parasites
and fungi. Most impressively, olive leaf extract was found to effectively
inhibit Staphylococcus aureus , a bacteria notorious for its ability
to mutate against antibiotics and responsible for many hospital-acquired
infections.
Olive leaf extract is a proven antimicrobial substance
that is safe for preventive and daily consumption. Olive leaf extract's
safety and efficacy has been demonstrated by hundreds of clinicians
around the country who have used olive leaf extract to treat their
patients with remarkable results.
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