In simplest terms, the immune system is a balanced
network of cells and organs that work together to defend you against
disease. It blocks foreign proteins from getting into your body. If a few
happen to sneak by your biological sentry, not to worry. With a powerful
"search and destroy" task force, your body deploys a host of additional
immune cell forces designed to hunt down these unwanted invaders and
ultimately works to destroy them.
Antibodies are proteins which can identify normal
"self" cells verses foreign invading cells. They work as part of the immune
system to destroy abnormal or foreign cells.
This, he says, not only affects your ability to fend off common
illnesses like colds, the flu, or a stomach virus, but it can also play a
role in protecting you against catastrophic diseases like cancer or even
heart disease.
Additionally, we also have a second protective response known as
the "cell-mediated immune system." This immunity involves immune system
cells, rather than proteins, which are "helper" or "killer" cells. The cells
help our body create memory of past defense against disease protection.
The immune system plays a key role in the body's
ability to fight infection and reduce the risk of developing tumors,
autoimmune and degenerative disease…www.ncbi.nlm.nih.gov
Reference Source -
Ohio
State University Medical Center
The organs involved
with the immune system are called the lymphoid organs, which affect growth,
development, and the release of lymphocytes (a certain type of white blood
cell). The blood vessels and lymphatic vessels are important parts of the
lymphoid organs, because they carry the lymphocytes to and from different areas
in the body. Each lymphoid organ plays a role in the production and activation
of lymphocytes. Lymphoid organs include:
- Adenoids (two glands located at the back of the nasal
passage)
- Appendix (a small tube that is connected to the large
intestine)
- Blood vessels (the arteries, veins, and capillaries through
which blood flows)
- Bone marrow (the soft, fatty tissue found in bone cavities)
- Lymph nodes (small organs shaped like beans, which are
located throughout the body and connect via the lymphatic vessels)
- Lymphatic vessels (a network of channels throughout the
body that carries lymphocytes to the lymphoid organs and bloodstream)
- Payer’s patches (lymphoid tissue in the small intestine)
- Spleen (a fist-sized organ located in the abdominal cavity)
- Thymus (two lobes that join in front of the trachea behind
the breast bone)
- Tonsils (two oval masses in the back of the throat)
What are lymphocytes?
Lymphocytes
- a type of infection-fighting white blood cell - are vital to an effective
immune system. Lymphocytes "patrol" the body for infectious
microorganisms.
How are lymphocytes formed?
All
cells, including immune cells such as lymphocytes, are produced in the bone
marrow (the soft, fatty tissue found in bone cavities). Certain cells will
become part of the group of lymphocytes, while others will become part of
another type of immune cells known as phagocytes. Once the lymphocytes are
initially formed, some will continue to mature in the bone marrow and become
"B" cells. Other lymphocytes will finish their maturation in the
thymus and become "T" cells. B and T cells are the two major groups of
lymphocytes, which recognize and attack infectious microorganisms.
Once mature, some lymphocytes will be housed in the lymphoid
organs, while others will travel continuously around the body through the
lymphatic vessels and bloodstream.
How do lymphocytes fight infection?
Although
each type of lymphocyte fights infection differently, the goal of protecting the
body from infection remains the same. The B cells actually produce specific
antibodies to specific infectious microorganisms, while T cells kill infectious
microorganisms by killing the body cells that are affected. In addition, T cells
release chemicals, called lymphokines, which trigger an immune response to
combat cancer or a virus, for example.
Other types of white blood cells, such as phagocytes
(engulfing cells) and cytotoxic cells (natural killer cells), actually kill the
infectious microorganism by "devouring" it.
What is natural and acquired immunity?
The
immune system has many different responsibilities. Not only does the immune
system provide protection from infection through natural barriers, but it also
adapts itself to provide immunity against infection by
"remembering" the infectious microorganism from a previous exposure.
The degree and duration of immunity depend on the type and amount of antigen and
how it enters the body.
Natural immunity
is created by the body's natural barriers, such as the skin, and protective
substances in the mouth, the urinary tract, and on the eye surface. Another type
of natural immunity is in the form of antibodies passed on from mother to child.
Acquired
immunity
develops through exposure to specific foreign microorganisms, toxins, and/or
foreign tissues), which are "remembered" by the body's immune system.
When that antigen enters the body again, the immune system "remembers"
exactly how to respond to it, such as with chickenpox. Once a person is exposed
to chickenpox or the chickenpox vaccine, the immune system will produce specific
antibodies against chickenpox. When that same person is exposed to chickenpox
again, the immune system will trigger the release of the particular chickenpox
antibodies to fight the disease.
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What
Are Disorders of the Immune System?
Reference Source -
Ohio
State University Medical Center
When
the immune system does not function properly, it leaves the body susceptible to
an array of diseases. Allergies and hypersensitivity to certain substances are
considered immune system disorders. In addition, the immune system plays a role
in the rejection process of transplanted organs or tissue. Other examples of
immune disorders include:
- Cancer of the immune system
- Autoimmune diseases, such as juvenile diabetes,
rheumatoid arthritis, and anemia
- Immune complex diseases, such as viral hepatitis and
malaria
-
Immunodeficiency diseases, such as acquired
immunodeficiency syndrome (AIDS)
www.niaid.nih.gov
Allergic
Diseases:
The most
common types of allergic diseases occur when the immune system responds to a
false alarm. In an allergic person, a normally harmless material such as grass
pollen or house dust is mistaken for a threat and attacked. Allergies such as
pollen allergy are related to the antibody known as IgE. Like other antibodies,
each IgE antibody is specific; one acts against oak pollen, another against
ragweed.
Autoimmune
Diseases:
Sometimes the immune system’s recognition apparatus breaks down,
and the body begins to manufacture T cells and antibodies directed against its
own cells and organs. Misguided T cells and autoantibodies,
as they are known, contribute to many diseases. For instance, T cells that
attack pancreas cells contribute to diabetes, while an autoantibody known as
rheumatoid factor is common in people with rheumatoid arthritis. People with
systemic lupus erythematosus (SLE) have antibodies to many types of their own
cells and cell components.
No one knows exactly what
causes an autoimmune disease, but multiple factors are likely to be involved.
These include elements in the environment, such as viruses, certain drugs, and
sunlight, all of which may damage or alter normal body cells. Hormones are
suspected of playing a role, since most autoimmune diseases are far more common
in women than in men. Heredity, too, seems to be important. Many people with
autoimmune diseases have characteristic types of self marker molecules.
Immune Complex Diseases:
Immune
complexes are clusters of interlocking antigens and antibodies. Normally, immune
complexes are rapidly removed from the bloodstream. Sometimes, however, they
continue to circulate, and eventually become trapped in the tissues of the
kidneys, the lungs, skin, joints, or blood vessels. There they set off reactions
with complement that lead to inflammation and tissue damage.
Immune complexes work their
mischief in many diseases. These include malaria and viral hepatitis, as well as
many autoimmune diseases.
Immunodeficiency Disorders:
When the immune system is missing one or more of its components,
the result is an immunodeficiency disorder. Immunodeficiency disorders can be
inherited, acquired through infection, or produced unintentionally by drugs such
as those used to treat people with cancer or those who have received
transplants.
Temporary immune
deficiencies can develop in the wake of common virus infections, including
influenza, infectious mononucleosis, and measles. Immune responses can also be
depressed by blood transfusions, surgery, malnutrition, smoking, and stress.
AIDS is an immunodeficiency
disorder caused by a virus (HIV) that infects immune cells. HIV can destroy or
disable vital T cells, paving the way for a variety of immunologic shortcomings.
HIV also can hide out for long periods in immune cells. As the immune defenses
falter, a person with AIDS falls prey to unusual, often life-threatening
infections and rare cancers.
A contagious disease, AIDS
is spread by intimate sexual contact, transfer of the virus from mother to
infant during pregnancy, or direct blood contamination. There is no cure for
AIDS, but newly developed antiviral drugs can slow the advance of the disease,
at least for a time. Researchers also are testing HIV vaccines in clinical
studies.
Cancers
of the Immune System:
The cells of the immune system, like other cells,
can grow uncontrollably, resulting in cancer. Leukemias are caused by the
proliferation of white blood cells, or leukocytes. The uncontrolled
growth of antibody-producing plasma cells can lead to multiple
myeloma. Cancers of the lymphoid organs, known as lymphomas, include
Hodgkin’s disease.
Immunity and Cancer
: When normal cells turn into cancer cells,
some of the antigens on their surface may change. If the immune system notices
the foreign antigens, it launches the body’s defenders, including killer T
cells, NK cells, and macrophages. But the immune system cannot patrol everywhere
to provide body wide surveillance, flushing out and eliminating all cells that
become cancerous. Tumors develop when the system breaks down or is overwhelmed.
The Immune System and the Nervous System:
Evidence
is mounting that the immune system and the nervous system are linked in several
ways. One well-known connection involves the adrenal glands. In response
to stress messages from the brain, the adrenal glands release hormones
into the blood. In addition to helping a person respond to emergencies by
mobilizing the body’s energy reserves, these “stress hormones” can stifle
the protective effects of antibodies and lymphocytes.
Hormones and other chemicals
known to convey messages among nerve cells have been found to “speak” to
cells of the immune system. Indeed, some immune cells are able to manufacture
typical nerve cell products, while some lymphokines can transmit information to
the nervous system. What’s more, the brain may send messages directly down
nerve cells to the immune system. Networks of nerve fibers have been found
connecting to the lymphoid organs.
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Mounting
an Immune Response
www.niaid.nih.gov
Infections
are the most common cause of human disease. They range from the common cold to
debilitating conditions like chronic hepatitis to life-threatening diseases such
as AIDS. Disease-causing microbes (pathogens)
attempting to get into the body must first move past the body’s external
armor, usually the skin or cells lining the body’s internal passageways.
The skin provides an
imposing barrier to invading microbes. It is generally penetrable only through
cuts or tiny abrasions. The digestive and respiratory tracts—both
portals of entry for a number of microbes—also have their own levels of
protection. Microbes entering the nose often cause the nasal surfaces to secrete
more protective mucus, and attempts to enter the nose or lungs can trigger a
sneeze or cough reflex to force microbial invaders out of the respiratory
passageways. The stomach contains a strong acid that destroys many pathogens
that are swallowed with food.
Bacteria, Viruses, and Parasites:
The most common disease-causing microbes are bacteria, viruses,
and parasites. Each uses a different tactic to infect a person, and, therefore,
each is thwarted by a different part of the immune system.
Most bacteria live in
the spaces between cells and are readily attacked by antibodies. When antibodies
attach to a bacterium, they send signals to complement proteins and phagocytic
cells to destroy the bound microbes. Some bacteria are eaten directly by
phagocytes, which signal to certain T cells to join the attack.
All viruses, plus a
few types of bacteria and parasites, must enter cells to survive, requiring a
different approach. Infected cells use their MHC molecules to put pieces of the
invading microbes on the cell’s surface, flagging down cytotoxic T lymphocytes
to destroy the infected cell. Antibodies also can assist in the immune response,
attaching to and clearing viruses before they have a chance to enter the cell.
Parasites live either
inside or outside cells. Intracellular parasites such as the organism that
causes malaria can trigger T-cell responses. Extracellular parasites are often
much larger than bacteria or viruses and require a much broader immune attack.
Parasitic infections often trigger an inflammatory response when eosinophils,
basophils, and other specialized granular cells rush to the scene and release
their stores of toxic chemicals in an attempt to destroy the invader. Antibodies
also play a role in this attack, attracting the granular cells to the site of
infection
Immune Tolerance:
Immune
tolerance is the tendency
of T or B lymphocytes to ignore the body’s own tissues. Maintaining tolerance
is important because it prevents the immune system from attacking its fellow
cells. Scientists are hard at work trying to understand how the immune system
knows when to respond and when to ignore.
Tolerance occurs in at least
two ways. Central tolerance occurs during lymphocyte development. Very early in
each immune cell’s life, it is exposed to many of the self molecules in the
body. If it encounters these molecules before it has fully matured, the
encounter activates an internal self-destruct pathway and the immune cell dies.
This process, called clonal deletion, helps ensure that self-reactive T cells
and B cells do not mature and attack healthy tissues.
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Infection
and Disease of
the Immune System
www.niaid.nih.gov
There are more than 150 different forms of primary immune deficiency
diseases (PIDDs) and, though they affect only about 500,000 people in the
United States, these diseases are chronic and debilitating.
www.historyofvaccines.org -
© The College of Physicians of Philadelphia
Infection occurs when a
pathogen invades body cells and reproduces. Infection will usually lead to
an immune response. If the response is quick and effective, the infection
will be eliminated or contained so quickly that the disease will not occur.
Sometimes infection
leads to disease. (Here we will focus on infectious disease, and define it
as a state of infection that is marked by symptoms or evidence of illness.)
Disease can occur when immunity is low or impaired, when virulence of the
pathogen (its ability to damage host cells) is high, and when the number of
pathogens in the body is great.
Depending on the
infectious disease, symptoms can vary greatly. Fever is a common response to
infection: a higher body temperature can heighten the immune response and
provide a hostile environment for pathogens. Inflammation, or swelling
caused by an increase in fluid in the infected area, is a sign that white
blood cells are on the attack and releasing substances involved in the
immune response.
Vaccination works to
stimulate a specific immune response that will create B and T cell responses
specific to a certain pathogen. After vaccination or natural infection,
long-lasting memory cells persist in the body and can lead to a quick and
effective response should the body encounter the pathogen again.
Vaccination works to
stimulate a specific immune response that will create memory B and
T cells
specific to a certain pathogen. These memory cells persist in the body and
can lead to a quick and effective response should the body encounter the
pathogen again.
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Vaccines
When Your Immune System Is Compromised
Reference Source -
www.health.harvard.edu
How vaccines work:
The
vaccination process mimics what would happen naturally when a potentially
harmful bacterium or virus breaches the body’s defenses, but with one
essential difference — there’s no harmful germ involved. Instead, the
vaccine contains a recognizable but defanged version of the pathogen. When
you’re vaccinated, your innate immune system is fooled into thinking that a
pathogen has gotten in.
A signal goes to the T cells and B cells of the adaptive immune system,
which quickly launch an attack as if a real pathogen were invading. Finally,
the response winds down, leaving in place the long-lived memory T cells and
B cells (see “Memory: Long-term protection”) fully briefed for future
encounters. Most vaccines don’t prevent pathogens from entering your body;
they just make sure your immune system blocks them quickly and keeps them
from making you sick.
How does vaccination accomplish its goal?
Most current vaccines work to
mobilize antibodies, proteins generated by a type of B cell known as a
plasma cell. Consequently, most of today’s effective vaccines work by
stimulating antibody-producing memory B cells. Antibodies are homing devices
of the immune system. They can lock on to the receptors of recognized bad
guys and block them from attacking your healthy cells.
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Types of Vaccines
Reference Source -
www.health.harvard.edu
Beware of
Live Attenuated Vaccines: These vaccines contain a live
microbe that is weakened in such a way that it can no longer cause disease.
Live attenuated vaccines elicit a strong immune response, involving both
memory B cells and memory T cells, and can confer lifelong immunity after as
few as one or two doses (see Figure 5).
There are drawbacks, however
. The attenuated form of
the pathogen in the vaccine could mutate (just as any other living organism
can mutate) and regain the ability to cause the disease.
This risk is
extremely small in healthy people but greater in people with already
compromised immune systems. For this reason, people with cancer or those
infected with HIV shouldn’t receive live attenuated vaccines. Another
drawback of live attenuated vaccines is that they must be stored in
refrigerators to keep them fresh and alive. This requirement is not a big
concern in developed countries, but it makes vaccines of this type, such as
the current measles vaccine, impractical in many developing countries where
immunization is desperately needed.
Inactivated or “killed” vaccines:
These
are the most common type of vaccine today. They are made with pieces of a
virus that has been killed with heat, chemicals, or radiation. Consequently,
inactivated (“killed”) vaccines don’t have the risk of mutating and
reverting back to their virulent form. They work by stimulating B cells to
produce antibodies. And they typically don’t require refrigeration. But
inactivated vaccines also have some drawbacks. The major one is they often
are not as potent as live attenuated vaccines because they only stimulate
the production of antibodies and don’t engage other aspects of the adaptive
immune system, such as the memory T cells. So to maintain immunity, you need
periodic booster shots.
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Signs of
Immunodeficiency Disorder
www.nlm.nih.gov
Your doctor
might think you have an immunodeficiency disorder if you have:
Other signs
include:
-
Poor response to treatment for infections
-
Delayed or incomplete recovery from illness
-
Certain types of cancers (such as Kaposi's
sarcoma or non-Hodgkin's
lymphoma)
-
Certain infections (including some forms of pneumonia or repeated
yeast infections)
www.healthguidance.org - Copyright 2014 Healthguidance.org. All rights
reserved.
Compromised Immune System:
Many
different people can suffer from a compromised immune system. Although we
typically think of those who suffer from HIV/AIDS and congenital diseases
that affect the immune system first, anyone can run the risk of an
improperly functioning immune system. AIDS and other diseases of the immune
system very often lead to numerous serious infections. Those whose immune
system is compromised for other reasons may only experience numerous colds
and viruses.
Many diseases are believed to be linked to dysfunction of the immune system.
Rheumatoid arthritis, ulcerative colitis, Crohn's disease, allergic rhinitis
and other allergies, as well as numerous other diseases are all
theoretically caused by improper immune system responses. It appears that
the immune system attacks healthy cells and in the case of allergies,
substances that would not cause infection, leading to inflammation. Because
of this belief, prescribed medications for these and other diseases can lead
to a compromised immune system. Corticosteroids and other
anti-inflammatories can reduce white blood cell counts.
Vitamin deficiencies, lack of proper rest, cigarette smoking and chronic
stress can all lead to a compromised immune system.
Proper nutrition is of utmost importance for anyone who wants a
well-functioning immune system and for overall good health. Immune system
aids or enhancers often include vitamin and mineral supplements,
particularly those that may be lacking from the average diet. The vitamins A
and C are particularly important, but need to be taken with the right
combination of other vitamins and minerals to work effectively. Taking a
good daily multi-vitamin is the easiest way to insure proper nutrition.
If one does
not get adequate amounts of sleep, then the immune system cannot repair
cells that were damaged during the day.
Those who are under chronic stress have been shown to have lower than normal
white blood cell counts.
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Nutrition,
Immunity, and Your Genes
Reference Source -
www.lef.org
Have
you ever noticed how some people seem never to get sick, but others are
constantly battling colds and the flu? Researchers are just now beginning to
understand how genes affect nutrition and overall immunity. It turns out that
the overall risk of contracting many diseases is influenced by genetics (Mathew
C 2001). A new field of nutritional genomics explores the interaction of
nutrition, genes, and environmental factors, including diet (Kaput J et al
2004).
This emerging field of
science evolved from the Human Genome Project, which mapped the human genome and
identified many genes that cause disease.
The association between diet
and chronic diseases such as atherosclerosis, diabetes, obesity, and cancer is
well known (Jenkins DJ et al 1997; Jenkins DJ et al 1999; Jenkins DJ et al 2000;
Kaput J et al 2004). Nutrients supplied by food are an important variable in
gene expression. Deficiency of some essential nutrients can alter metabolism and
the structure of DNA (Kaput J et al 2004). A well-studied example of the
relationship between genetics and diet is type 2 diabetes. This condition is
associated with a sedentary lifestyle, being overweight, and ethnicity. Although
some individuals are genetically predisposed to this condition, many can control
symptoms through exercise and a change in diet (Kaput J et al 2004).
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Foods
That Boost Your Immune System
Reference Source -
www.bloodindex.org
Diet
and Nutrition form the basic foundation for health and its development. Good
nutrition means stronger immune systems, less illness and better health.
Vitamin C
- Sources: bell pepper, broccoli, brussel sprouts, cauliflower, fruit
juices, lemon juice, mustard greens, oranges, papaya, strawberries
Foods with vitamin C
increase the production of infection-fighting white blood cells and increase
levels of interferon, the antibody that coats cell surfaces preventing the entry
of viruses.
Vitamin E - Sources:
almonds, broccoli, chard, mustard greens, olives, papaya, sunflower seeds,
turnip greens
Vitamin E stimulates the production of natural "killer" cells (cells
that seek out and destroy germs and cancer cells). Vitamin E enhances the
production of B-cells, the immune cells that produce antibodies that destroy
bacteria. Vitamin E may also reverse some of the decline in immune response
commonly seen in aging.
Vitamin B12 - Sources:
beef, halibut, lamb, milk, salmon, scallops, shrimp, snapper
Vitamin B12 is central to immune processes because, without adequate B12, white
blood cells can't mature and multiply. Folic acid also plays a key role in
immune system development and maintenance.
Zinc - Sources:
oysters,
mushrooms, meat, legumes
This valuable mineral increases the production and effectiveness of white blood
cells that fight infection. Zinc also increases killer cells that fight against
cancer and it helps white cells release more antibodies. Zinc also increases the
number of infection-fighting T-cells, especially in elderly people, who are
often deficient in zinc and whose immune system often weakens with age. The
anti-infection hype around zinc is controversial. While some studies claim that
zinc supplements in the form of lozenges can lower the incidence and severity of
infections, other studies have failed to show this correlation.
A word of
caution: too much zinc (more than 75 milligrams a day) in the form of
supplements can inhibit immune function.
Chromium - Sources:
brewer's yeast, oysters, liver, onions, whole grains, bran cereals, tomatoes,
potatoes
Many people do not get enough chromium in their diet due to food processing
methods that remove the naturally occurring chromium in commonly consumed foods.
Recent research in animal models shows that chromium can enhance the ability of
white blood cells to respond to infection.
Selenium
- Sources: Brazil nuts, brown rice, cottage cheese, chicken (white meat),
egg yolks, garlic, halibut, lobster, mushrooms, pork, salmon, shrimp, snapper,
sunflower seeds, tuna, whole grains.
This mineral increases natural killer cells
and mobilizes cancer-fighting cells.
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Restoring
the Immunity Naturally
Reference Source -
www.health.harvard.edu
What can you do? On the whole,
your immune system does a remarkable job of defending you against
disease-causing microorganisms. But sometimes it fails: A germ invades
successfully and makes you sick. Is it possible to intervene in this process
and make your immune system stronger? What if you improve your diet? Take
certain vitamins or herbal preparations? Make other lifestyle changes in the
hope of producing a near-perfect immune response?
The idea of boosting your immunity is enticing, but
the ability to do so has proved elusive for several reasons. The immune
system is precisely that — a system, not a single entity. To function well,
it requires balance and harmony. There is still much that researchers don’t
know about the intricacies and interconnectedness of the immune response.
For now, there are no scientifically proven direct links between lifestyle
and enhanced immune function.
But that doesn’t mean the effects of lifestyle on
the immune system aren’t intriguing and shouldn’t be studied. Quite a number
of researchers are exploring the effects of diet, exercise, age,
psychological stress, herbal supplements, and other factors on the immune
response, both in animals and in humans. Although interesting results are
emerging, thus far they can only be considered preliminary. That’s because
researchers are still trying to understand how the immune system works and
how to interpret measurements of immune function. The following sections
summarize some of the most active areas of research into these topics. In
the meantime, general healthy-living strategies are a good way to start
giving your immune system the upper hand.
Adopt healthy-living strategies:
Your first line of defense is to choose a healthy lifestyle. Following
general good-health guidelines is the single best step you can take toward
keeping your immune system strong and healthy. Every part of your body,
including your immune system, functions better when protected from
environmental assaults and bolstered by healthy-living strategies such as
these:
-
Don’t smoke.
-
Eat a diet high in fruits, vegetables, and whole
grains, and low in saturated fat.
-
Exercise regularly.
-
Maintain a healthy weight.
-
Control your blood pressure.
-
If you drink alcohol, drink only in moderation.
-
Get adequate sleep.
-
Take steps to avoid infection, such as washing
your hands frequently and cooking meats thoroughly.
-
Get regular medical screening tests for people
in your age group and risk category.
Herbs and other supplements:
Walk into a store, and you will find bottles of pills and herbal
preparations that claim to “support immunity” or otherwise boost the health
of your immune system. Although some preparations have been found to alter
some components of immune function, thus far there is no evidence that they
actually bolster immunity to the point where you are better protected
against infection and disease. Demonstrating whether an herb — or any
substance, for that matter — can enhance immunity is, as yet, a highly
complicated matter. Scientists don’t know, for example, whether an herb that
seems to raise the levels of antibodies in the blood is actually doing
anything beneficial for overall immunity.
But that doesn’t mean we should discount the
benefits of all herbal preparations. Everyone’s immune system is unique.
Each person’s physiology responds to active substances differently. So if
your grandmother says she’s been using an herbal preparation for years that
protects her from illness, who’s to say that it doesn’t? The problem arises
when scientists try to study such a preparation among large numbers of
people. The fact that it works for one person won’t show up in the research
data if it’s not doing the same for a larger group.
Scientists have looked at a number of herbs and
vitamins in terms of their potential to influence the immune system in some
way. Much of this research has focused on the elderly, children, or people
with compromised immune systems, such as AIDS patients. And many of the
studies have had design flaws, which means further studies are needed to
confirm or disprove the results. Consequently, these findings should not be
considered universally applicable.
Some of the supplements that have drawn attention
from researchers are these:
Aloe vera. For now, there’s no evidence that
aloe vera can modulate immune response. Because many different formulations
and compounds have been used in studies, comparing the results is difficult.
However, there is some evidence that topical aloe vera is helpful for minor
burns, wounds, or frostbite, and also for skin inflammations when combined
with hydrocortisone. Studies have found aloe vera is not the best option for
treating breast tissue after radiation therapy.
Astragalus membranes. The astragalus product,
which is derived from the root of the plant, is marketed as an immune-system
stimulant, but the quality of the studies demonstrating the
immune-stimulating properties of astragalus are poor. Furthermore, it may be
dangerous.
Echinacea. An ocean of ink has been spilled
extolling echinacea as an “immune stimulant,” usually in terms of its
purported ability to prevent or limit the severity of colds. Most experts
don’t recommend taking echinacea on a long-term basis to prevent colds. A
group of physicians from Harvard Medical School notes that studies looking
at the cold prevention capabilities of echinacea have not been well
designed, and other claims regarding echinacea are as yet not proven.
Echinacea can also cause potentially serious side effects. People with
ragweed allergies are more likely to have a reaction to echinacea, and there
have been cases of anaphylactic shock. Injected echinacea in particular has
caused severe reactions. A well-designed study by pediatricians at the
University of Washington in Seattle found echinacea didn’t help with the
duration and severity of cold symptoms in a group of children. A large 2005
study of 437 volunteers also found that echinacea didn’t affect the rate of
cold infections or the progress and severity of a cold.
Garlic. Garlic may have some
infection-fighting capability. In laboratory tests, researchers have seen
garlic work against bacteria, viruses, and fungi. Although this is
promising, there haven’t been enough well-designed human studies conducted
to know whether this translates into human benefits. One 2006 study that
looked at rates for certain cancers and garlic and onion consumption in
southern European populations found an association between the frequency of
use of garlic and onions and a lower risk of some common cancers. Until more
is known, however, it’s too early to recommend garlic as a way of treating
or preventing infections or controlling cancer.
Ginseng. It’s not clear how the root of the
ginseng plant works, but claims on behalf of Asian ginseng are many,
including its ability to stimulate immune function. Despite the claims of a
number of mainly small studies, the National Center for Complementary and
Alternative Medicine (NCCAM) considers there have been insufficient large
studies of a high enough quality to support the claims. NCCAM is currently
supporting research to understand Asian ginseng more fully.
Glycyrrhiza glabra (licorice root). Licorice root is used in Chinese
medicine to treat a variety of illnesses. Most studies of licorice root have
been done in combination with other herbs, so it’s not possible to verify
whether any effects were attributable to licorice root per se. Because of
the potential side effects of taking licorice and how little is known about
its benefits — if any — for stimulating immune function, this is an herb to
avoid.
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Supporting
a Healthy Immune System
Reference Source
-
www.lef.org
A healthy immune system
grows ever more important as we age, and immune status is closely associated
with nutrition, exercise, and stress reduction. Older people and people with
compromised immune systems should talk to their physician about exercising,
reducing stress, and designing an active, immune-boosting nutritional program.
Glutathione
boosters. Glutathione is probably
the body's most
important cellular defense against free radical damage. It is a free radical
scavenger and major antioxidant.
Low levels of glutathione
are linked to many diseases. Malnutrition and aging (Cai J et al 2000) deplete
glutathione. Glutathione is also involved in one of the major liver
detoxification pathways.
Glutathione is produced in
the body, and it is not easily absorbed when taken orally. Instead, glutathione
precursors may be used by the body to increase glutathione (Bounous G 2000).
Glutathione precursors include glutamine, N-acetylcysteine (NAC), and S-adenosyl-L-methionine
(SAMe) (Devlin T 2002). It can also be upregulated by lipoic acid and vitamins C
and E.
Glutamine. Glutamine is the most
abundant amino acid in the body (Roth E 2002). Glutamine depletion causes
down regulation of glutathione levels in the body (Roth E 2002), and dietary
supplementation increases it (Roth E 2002). Glutamine has immunoregulative
activities (Roth E 2002; Li J et al 1995). Lymphocytes and macrophages use
glutamine at a very high rate (Newsholme E 1994). Glutamine stimulates
lymphocyte production and killer immune cell activity (Rohde T et al 1995;
Rohde T et al 1998; Rohde T et al 1996; Jurectic A et al 1994).
Glutamine depletion slows wound healing and increases
the risk of organ failure under certain conditions (Wilmore DW 1991).
Endurance athletes whose muscles do not fully recover between workouts have
decreased glutamine levels (Shephard RJ et al 1998; Castell LM et al 1998).
Some scientists believe that intense physical exercise or stress due to
trauma, burns, or sepsis (blood infection) forces the body into glutamine
debt, which temporarily compromises immune function (Newsholme E 1994).
SAMe. SAMe is a natural amino acid
present throughout the body. It is crucially important because it is
involved in dozens of chemical reactions, including the synthesis of DNA and
RNA, proteins, melatonin, creatine, and many others. SAMe is an important
energy source (Osman E et al 1993) and is intrinsically related to the
synthesis of glutathione.
NAC. NAC acts as an antioxidant and
is recommended for conditions that increase oxidative stress or decrease
glutathione levels (Burgunder JM et al 1989). NAC has a protective effect on
DNA and is a powerful free radical scavenger. It increases the synthesis of
glutathione only when there is a demand and is thought to concentrate only
in tissues where it is required (Burgunder JM et al 1989). NAC can modulate
the concentrations of certain cytokines. In laboratory studies, it has
increased IL-1 and IL-2 levels when they are at low concentrations and
decreased these cytokines at higher concentrations (Baier JE et al 1996). It
has also demonstrated an ability to inhibit cell growth and proliferation in
cancer cell lines (Chiao JW et al 2000) and prevent the transformation of
carcinogens into more toxic compounds (De Flora S 1984; Wilpart M et al
1986).
www.healthguidance.org - Copyright Healthguidance.org. All rights
reserved.
Boosting the immune system:
Vitamin supplementation and immune system aids, like the herb
Andrographis Paniculata
(AP) can be particularly helpful. Although some herbalists still recommend
Echinacea, it has been shown to have toxic effects on the liver when used
for extended periods of time.
Animal studies have shown that AP, even in large amounts is non-toxic.
Immune system aids or enhancers, such as AP, have been shown in laboratory
tests to increase white blood cell counts, reduce risks of infection and
reduce the number of complications associated with common viruses, such as
influenza. Beta glucans, a biologically active plant component, has been
shown to stimulate the immune system, protect against colds, flu and
infections, as well as AIDS by inhibiting viral replication.
Reference Source -
www.drweil.com
There
are also several herbs, such as astragalus, that can help enhance immune
function. Obtained from the root of
Astragalus
membranaceous in the pea family, astragalus has a long history in Chinese
medicine, where it is used to ward off colds and flu. It is widely available and
inexpensive, and can be beneficial for:
-
Those with immune
deficiencies
-
People who "get
everything going around" and want to boost their immunity during the
flu season
-
Cancer patients who are
undergoing chemotherapies which suppress immune function
The
General
Immune Support formula available on
Dr.
Weil’s Vitamin Advisor is recommended for people who get
frequent colds. Featuring Astragalus and a combination of polypore mushrooms
that may help support a healthy immune system.
www.jonbarron.org
-
The Baseline of Health Foundation
"Written by Jon Barron at The Baseline of Health Foundation" - Taking systemic/proteolytic
enzymes between meals relieves stress on the immune system by helping to
eliminate Circulating Immune Complexes from the body.
Proper diet and nourishment
boost your immune system. Each and every immune cell in your body is
manufactured from the food you eat. A nutritionally deficient diet means
functionally deficient immune cells. Liquid trace mineral supplements and living
matrix vitamin supplements enhance the production of your body's immune cells.
Immunomodualtors such as L-carnosine
and CMO (cetyl-myristoleate) help keep the immune system properly programmed so
it doesn't attack itself.
Full spectrum antioxidant
formulas boost the immune system in multiple ways. Just one example is Curcumin.
In Immunological Investigations, 1999, Vol 28, Iss 5-6, pp 291-303 there are
published studies that prove that Curcumin can increase white blood cell count
by some 50% in just 12 days -- not to mention circulating antibodies by some 512
times in the same timeframe.
Cleaning out the liver with
a good liver detox program improves your liver's ability to produce immune
factors and remove bacteria from the blood. Cleaning out the blood with a good
blood cleansing formula and balancing your blood's pH with alkalinizing formulas
or high pH water also helps to improve immune function. And of course, immune
boosting formulas and pathogen destroying formulas are specifically designed to
improve immune function and directly destroy invading pathogens.
Use a good probiotic and you
substantially boost your immune system by increasing internal production of a
number of powerful immune factors. …Read in its entirety
The Baseline of Health Foundation - www.jonbarron.org
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The
Role of Nutrition, Exercise and Stress
www.breastcancer.org -
© Breastcancer.org - All rights
reserved.
Complementary approaches to
fighting infection and cancer:
Nutrition, stress reduction, support groups, exercise—intriguing new studies
suggest that these fundamental but non-traditional interventions may
strengthen the immune system. For example, improved immune cell function has
been documented after people with melanoma, a malignant skin cancer,
attended regular support group meetings. Other studies find that women in
breast cancer support groups live longer than those who don't join such
groups. Researchers speculate that one reason is the stress-reducing,
immune-supporting effects that these groups provide.
Nutrition
:
Any thing your body does is crippled by poor nutrition. This is true for
healing a wound, building immune cell blood counts, and even managing
stress. Attention to good nutrition makes sense whether it specifically
benefits the immune system or not.
The power of nutrition to strengthen the immune
function is not yet fully understood. But two leaders in the field: Dr.
Keith Block (University of Illinois and the Block Medical Center, Evanston,
Illinois), and Dr. Mitch Gaynor (Strang-Cornell Cancer Prevention Center,
New York City), focus on nutrition as a means of reducing cancer risk and
cancer death and increasing quality of life. Their work emphasizes
vegetarian diets and fat restriction, coupled with stress reduction and
other complementary medicine therapies. They believe these factors combine
to strengthen the immune system.
Proponents
of these innovative, non-traditional therapies say that excess weight and eating
too much cholesterol and other fats are risk factors for cancer. They say that
fat appears to reduce white cell production, affecting
T-cell and macrophage
activity. Further, they say, obesity and a poor diet
compromise the lymphatic system, making the body more vulnerable to infection
and disease. Eating large amounts of protein, such as that found in animal
products, they believe, contributes to these undesirable effects. Thus, their
nutritional programs strictly limit proteins that come from animal foods and
unhealthy fats. In particular, stick to the monounsaturated fats like canola oil
and olive oil, and avoid saturated fats like coconut oil, palm oils, and animal
fats.
Supplements
vs. food: All experts agree that vitamins and other important
nutrients are best eaten in whole foods rather than swallowed as processed
supplements. Whole foods may contain many other valuable components that we
currently know little about. Fresh fruits and vegetables, SURE grains,
mushrooms, herbs, teas, omega-3 fatty acids (found in freshwater fish like
salmon and mackerel), complex carbohydrates, yogurt, and seaweed are believed to
increase the activity of T cells and their escort cells, and to increase the
production of antibodies and fighting cells.
In
traditional Chinese medicine, herbal remedies and food are part of the same
spectrum. Herbs may be used as a medicine. Usually a carefully selected
combination of herbs are used together, which might come from the root, bark,
leaves, or seeds of various plants). Or herbs may be incorporated into food as
an ingredient (mushrooms) or as a spice (cilantro). In both instances, the herbs
enhance your well-being. Anything that improves overall health is also likely to
strengthen the immune system.
Exercise:
Researchers have long observed the positive effects of moderate amounts of
exercise on the immune system. Now they're beginning to look at the effects
moderate exercise can have on the immune systems of cancer patients in the midst
of treatment. In one small study, researchers found that moderate exercise
(three or more times a week) increased the immune cell counts of women
undergoing breast cancer treatment back to normal levels, and also improved the
women's mood and ability to handle their feelings comfortably.
Stress
reduction: It's well known that chronically high levels of stress
hormones (like adrenaline) suppress the immune system and reduce the body's
ability to defend or repair itself. That's why many cancer centers and hospitals
have begun offering stress reduction therapy along with traditional cancer
treatments such as chemotherapy and radiation. Meditation, visualization, yoga,
and other relaxation techniques may help bolster your immune system and assist
in fighting the effects of the cancer. Talk to your doctor or nurse about using
these techniques in conjunction with your regular treatment.
www.psychologytoday.com - ©
Copyright 2002-2014 Sussex Publishers, Publishes
2011/04 - Mood-Gut-Bacteria-and-the-Immune-System
Many people would be surprised that the immune system, the gastro-intestinal
tract and stress
interact, but that is what the most recent of a number of studies shows.
In this study on mice, (Brain,
Behavior, and Immunity Volume 25, Issue 3, March
2011, Pages 397-407)
researchers demonstrated that psychological stress causes almost immediate
changes to the gut bacterial population, and that some of these affected
sub-populations strongly influence the effect that stress has on immunity.
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The Gut and Your Immune System
Reference Source -
ffhi.ucdavis.edu
- UC Davis Food for Health Institute
The Gut Response and the Immune: The human gastrointestinal (GI)
tract harbors >80% of the immune cells in the body and also hosts
10 times more commensal bacteria than the total number of cells in the body.
The immune cells are essential for protection against pathogens yet
uncontrolled immune activation can cause chronic inflammatory diseases. The
interplay of the gut immune system with pathogens and commensal microbiota
shapes the integrity and protection to the gut epithelial barrier and immune
cells that in turn controls inflammation. Unresolved inflammation
contributes to tissue injury, changes in the gut microbiota and inflammatory
diseases.
Reference -
www.vitabase.com
Our large intestines are inhabited by trillions of
bacteria often referred to as probiotics (pro=encouraging, biotic=life).
These bacteria composed primarily of acidophilus and bifidobacterium species
are introduced to our system during the birth process and play a crucial
role in our health. Without probiotics, humans would be extremely vulnerable
to food borne illnesses, be deficient in key nutrients and vitamins, and
have a much weaker immune system in general.
Lifestyle factors play a
significant role in determining how friendly our large intestines are to
hosting these important bacteria. Eating a diet high in sugar, fat and
processed foods prevents them from growing and thriving. Consumption of
fiber from fruits, vegetables and whole grains along with lean proteins like
fish, chicken and turkey helps to create an environment that promotes the
growth of probiotics. In addition, the frequent use of antibiotics in our
society can greatly disturb the probiotic flora in the gut. Although these
antibiotics are intended to kill only the bad bacteria, they also affect the
good ones. This is why many people experience diarrhea and yeast infections
when they take antibiotics. As the good probiotic bacteria are killed, bad
(pathogenic) organisms like yeast are able to get a foot hold in the system.
Frequent or long term antibiotic use can dramatically alter the gut flora
and can be a significant contributing factor to other long term health
problems related to immune dysfunction and intestinal conditions.
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Maintaining Gut Health
www.todaysdietitian.com - News Article 06-01-12 - p58
When it comes to gut health, Kathie Madonna Swift, MS, RD, LDN, coauthor of The
Inside Tract: Your Good Gut Guide to
Digestive Health, said
in the March 21, 2012, webinar “Functional Nutrition and the Gut” that “diet
and nutrition therapy should be the first route [to obtaining gut health],
not the alternative. In Western medicine, they [prescribe] medicine.” Based
on several studies, the current medical focus is on treatment rather than
prevention. Several drugs exist to treat acute inflammatory bowel disease
(IBD), for example, but none to prevent it.
The research behind what’s known as the hygiene hypothesis says
an imbalance within the gut will impair the gut barrier and increase risk to
gut health and of developing disease. Conditions that cause imbalance can be
an unbalanced diet but also may be lack of exercise or chronic stress.
Recent studies have shown that high dietary fat and high fructose disturb
the GI barrier, which can lead to fatty liver disease and inflammation.1 On
the other hand, positive changes in the diet have been shown to help prevent
major diseases such as obesity, allergy, and cancer.1 As more research shows
the key role that diet and lifestyle play in maintaining gut health and
preventing GI diseases, including infection, IBD, and food allergies, Swift
says, “We [dietitians] have to be the change agent to make this happen.”
Swift says processed foods and today’s grains vs. ancient grains
have a big impact on gut function. To help improve it and prevent disease,
she counsels clients to feed gut flora by “plant centering the plate” and
eating foods that are nutrient dense, high in fiber, and have a low glycemic
load.
As a proponent of the RD’s role in public health,
Rao agrees. Dietitians would do well to counsel clients to eat
“health-promoting diets and, in particular, diets that help promote the
predominance of the beneficial bacteria,” he says. Because probiotic
bacteria use complex carbohydrates such as dietary fiber and harmful
bacteria use dietary proteins and fats to produce toxins that can damage
good health, Rao suggests a diet that’s a “good source of complex
carbohydrates and low in red meats, which are sources of protein and
saturated lipids. Good food sources of complex carbohydrates include fruits,
vegetables, legumes, and cereals. Another important recommendation is to
include foods that are rich sources of antioxidants such as fruits and
vegetables.”
Specific Signs
of Gastrointestinal (GI) Health
-
Normal nutritional status and effective absorption of food, water, and
minerals
-
Regular bowel movement, normal transit time, and no abdominal
pain
-
Normal stool consistency and rare nausea, vomiting, diarrhea,
constipation, and bloating
Absence of GI
Illness
-
No acid peptic disease, gastroesophageal reflux disease, or other
gastric inflammatory disease
-
No enzyme deficiencies or carbohydrate intolerances
-
No inflammatory bowel disease, celiac disease, or other
inflammatory state
-
No colorectal or other GI cancer
Normal and
Stable Intestinal Microbiota
-
Normal composition and vitality of the gut microbiome
-
No GI infections or antibiotic-associated diarrhea
-
No bacterial overgrowth
Effective
Immune Status
-
Effective GI barrier function, normal mucus production, and no enhanced
bacterial translocation
-
Normal levels of immunoglobulin A, normal numbers and normal
activity of immune cells
-
Immune tolerance and no allergy or mucosal hypersensitivity
Status of
Well-Being
-
Normal quality of life
-
Qi (ch’i) or positive gut feeling
-
Balanced serotonin production and normal function of the enteric
nervous system
“Food is central, but supplements
can be helpful,” Swift adds. Most notable in supporting gut health are
supplements
containing probiotics or prebiotics.
top
Probiotic
Immune Therapy
jn.nutrition.org -
Copyright © by the American Society for
Nutrition
Among the numerous purported health benefits
attributed to probiotic bacteria, their capacity to interact with the immune
system of the host is now supported by an increasing number of in vitro and
in vivo experiments. In addition to these, a few well-controlled human
intervention trials aimed at preventing chronic immune dysregulation have
been reported. Even though the precise molecular mechanisms governing the
cross-talk between these beneficial bacteria and the intestinal ecosystem
remain to be discovered, a new and fascinating phase of research has been
initiated in this area as demonstrated by a series of recent articles…
In conclusion, it is evident that the analysis of
the impact of probiotics on the host immune system has entered a new and
fascinating phase of research and that this effort is likely to offer novel
and useful means to modulate host immunity for protection from, or treatment
of, a wide variety of human and animal disorders.
www.webmd.com
-
© WebMD, LLC. All rights reserved.
There’s also evidence that
probiotics help maintain a strong immune system. “In societies with very
good hygiene, we’ve seen a sharp increase in autoimmune and allergic
diseases,” Guandalini tells WebMD. “That may be because the immune system
isn’t being properly challenged by pathogenic organisms. Introducing
friendly bacteria in the form of probiotics is believed to challenge the
immune system in healthy ways.”
Probiotics
May Help Lots of Ailments: Although they
are still being studied, probiotics may help several specific illnesses,
studies show. In 2011, experts at Yale University reviewed the research.
They concluded that probiotics are most effective for:
-
Treating childhood diarrhea
-
Treating ulcerative colitis
-
Treating necrotizing enterocolitis, a type of
infection and inflammation of the intestines mostly seen in infants
-
Preventing antibiotic-associated diarrhea and
infectious diarrhea
-
Preventing pouchitis, an inflammation of the
intestines that can follow intestinal surgery
-
Treating and preventing eczema associated with
cow’s milk allergy
-
Helping the immune system
The Yale University panel of experts concluded that
probiotics may be helpful in other ways, although the evidence is less
convincing. These include:
Probiotics may also be useful in unexpected ways. A study published in 2010
suggests that probiotics may lower the risk of common childhood illnesses
such as ear infections, strep throat, and colds.
Reference Source -
www.vitabase.com
Protecting the System:
Probiotic bacteria are unique in that they do not
cause infection and actually help to prevent infection from other aggressive
micro-organisms related to food borne illnesses like salmonella and bacteria
associated with traveler’s diarrhea. When healthy populations of probiotics
are present in the large intestine, other bacteria that can potentially make
us ill are crowded out, preventing them from causing a major infection.
Without them we would be extremely susceptible to food borne infection.
The role of probiotics in immune function has been
studied for decades. Scientists were curious as to why our bodies would
strike up such a close relationship with these bugs. The most crucial role
probiotics seem to play for humans is that of training the immune system.
Most people don’t know that 60-70% of their immune system is located in the
gut as a vast network of lymph tissue referred to as GALT (gut associated
lymphatic tissue). The probiotics in our gut are constantly interfacing with
the GALT and essentially priming the immune system for contact with other
bacteria. They serve as a way for the body to learn how to respond to
bacteria without actually having to suffer an infection. This becomes
particularly important in young children whose immune system is in constant
state of development until about age 7.
Link to
Probiotics in Colon Treatment for additional information
Reference Source -
www.usprobiotics.org
Why Probiotics?
Scientists
are learning more each day about the role of microbes in keeping people healthy
and the multitude of health benefits associated with consuming the right type
and levels of probiotic microbes.
Research
has suggested that probiotic bacteria can:
Some
preliminary studies also report that certain probiotics can play a role in
reducing the development of allergy in children, decreasing Helicobacter
pylori colonization of the stomach, helping patients cope with side effects
of antibiotic therapy, managing relapse of some inflammatory bowel conditions,
decreasing the risk of certain cancers, decreasing dental-caries-causing
microbes in the mouth, and keeping healthy people healthy.
Role of Probiotics in
Health
-
For
centuries, folklore suggested that fermented dairy products containing live
active cultures are healthful. Recent controlled scientific investigation
supports these traditional views, suggesting that probiotics are a valuable part
of a healthy diet. In addition, the emergence of some new public health risks
suggests an important role for effective probiotics in the mitigation of
illness. For example, the ability of probiotic bacteria to support the immune
system could be important to the elderly or other people with compromised immune
function. (It is important that immune compromised individuals ask their doctor
before taking any dietary supplement, including probiotics.)
Infections
are another area with potential for probiotics. Some infections, once thought
self-limiting or readily treatable with antibiotics, are now recognized as more
serious health threats. Bacterial vaginosis used to be considered just an
annoyance. Now we know it is associated with low birth weight infants and
increased risk of sexually transmitted diseases. New food borne pathogens have
emerged as prevalent and life threatening, including Shiga-like
Escherichia
coli strains. Multiple antibiotic resistances are a continual threat in the
battle against once-treatable infections. And in non-industrialized nations,
infections such as rotavirus claim the lives of hundreds of thousands of infants
yearly. Prevention of infections before they occur is clearly the better
alternative. Certain probiotics may be a safe, cost-effective approach that
adds a barrier against microbial infection.
How Probiotics Work
-
Microbes
have been found to play an important role in human health. Most of these
bacteria are not harmful, and in fact contribute positively to normal human
growth and development. But some of these bacteria can have negative influences.
It is therefore important that the balance of microbes be maintained to favor
the beneficial bacteria over the potentially harmful ones...
These colonizing microbes have been shown to have
important roles in digestion, metabolism, vitamin synthesis, host cell
development, immune system function, intestinal barrier function, defense
against pathogens, and other activities that are critical to human health.
The importance of this colonization to human health and development is
reflected in the concept that humans are in effect “superorganisms”,
composed of their own human genome and the combined microbes that colonize
them.
Taking this into consideration, it is not surprising
that probiotics – by directly or indirectly influencing the populations or
activities of our colonizing microbes – can impact human health.
Microbe Role in GI Tract - The microbes present in
the gastrointestinal tract have the potential to act in a positive, negative
or neutral manner…It is known that microbes in the large intestine complete
the digestion process on any food components that were not digested in the
small intestine, such as lactose in lactose intolerant people or fibers
resistant to the enzymes they encounter in the small intestine. There is
evidence of non-digestive microbial activities as well. Certain intestinal
microbes are known to produce vitamins.
Also, in studies done with special microbe-free
laboratory animals, evidence is strong that without
normal microbial populations, the immune system functions poorly, and
resistance to pathogenic bacteria is greatly reduced. Other evidence
suggests that intestinal microbes might act on pre-carcinogenic or mutagenic
(capable of inducing genetic mutation) compounds. Depending on the specific
microbe, mutagenic or carcinogenic activity can be either increased or
decreased.
Immune
System Modulation
-
The
immune system defends against microbial pathogens that have entered our bodies.
The immune system is extremely complex, involving both cell-based and
antibody-based responses to potential infectious agents. Immunodeficiency can
result from certain diseases (e.g., cancer, AIDS, leukemia) or, to a lesser
extent, from more normal conditions such as old age, pregnancy, or stress.
Autoimmune diseases (e.g., allergies, rheumatoid arthritis, inflammatory bowel
diseases) also can occur due to misdirected immune system activity.
Probiotic
cultures have been shown in a variety of test systems to stimulate certain
cellular, biochemical and antibody functions of the immune system (read
more). Animal and some human studies have shown an effect of yogurt
or lactic acid bacteria on enhancing levels of certain immunoreactive cells
(e.g. macrophages, lymphocytes) or on regulation of immune factors (cytokines,
immunoglobulins, interferon). In addition, some studies have shown improved
survival of pathogen-infected laboratory animals consuming probiotic cultures as
compared to animals consuming a control diet. Results accumulated so far suggest
that probiotics may provide an additional tool to help your body protect itself.
An
exciting area of research has been documenting the ability of certain probiotic
bacteria to modulate immune dysregulation. Studies have shown that probiotics
are effective in decreasing the development of allergy and relapse of
inflammatory bowel disease.
Choosing a Probiotic
-
The
potential benefits of probiotic cultures seem vast. The applications range
from helping to treat acute intestinal infections to aiding in the digestion of
lactose and contributing, over the longer term, to improved health and possibly
reduced risk of disease.
What
should be considered when choosing a probiotic? Microbiologists agree that it cannot be assumed that research
published on one strain of probiotic applies to another strain, even of the same
species. (Remember, for the strain "Lactobacillus rhamnosus GG",
the genus is Lactobacillus, the species is rhamnosus and the
strain designation is GG. Another strain of L. rhamnosus, for example
strain GR-1, has different probiotic properties.) Therefore, documentation of
type of bacteria (genus, species and strain), potency (number of viable bacteria
per dose), purity (presence of contaminating or ineffective bacteria), and
the
extent of research that has been published on health effects, must be provided
for any strain being used in a product. Usually the culture or product
manufacturer can provide this information.
Cautions
about Probiotics
www.webmd.com
-
© WebMD, LLC. All rights reserved
For the most part,
taking probiotics is safe and causes few side effects. “People in cultures
around the world have been eating yogurt, cheeses, and other foods
containing live cultures for centuries,” says Martin Floch, MD, a professor
of gastroenterology at Yale University, co-author of Probiotics: A Clinical
Guide, and a consultant for the Dannon Company.
Still, probiotics may be
dangerous for people with weakened immune systems or serious illnesses.
One study found that patients with severe
pancreatitis who were given probiotics had a higher risk of death.
Reference Source -
www.health.harvard.edu
…Another caution is that
the quality of probiotic products is not consistent. Some contain
what they say they do; some do not. In a 2006 report, the American Academy
of Microbiology said that “at present, the quality of probiotics available
to consumers in food products around the world is unreliable.” In the same
vein, the FDA monitors food packages to make sure they don’t carry labels
that claim the products can cure diseases unless the companies have
scientific evidence to support the claims. Does this
mean taking probiotics is useless? No. It means the jury is still out
on the expansive health claims. In the meantime, if you choose to take a
probiotic in moderation, it probably won’t hurt, and the scientific evidence
may ultimately show some benefit.
www.berkeleywellness.com - © REMEDY HEALTH MEDIA, LLC All rights
reserved
Even if probiotics are
beneficial for certain medical conditions, you’d have to take the right
strain and right dose, which even scientists don’t know for certain.
And not everyone will even respond the same way to a given probiotic—much
depends on the intestinal bacteria you have to begin with, your immune
status and other factors.
In addition, there’s no guarantee that products contain
the numbers of organisms claimed on labels—or that the organisms are even
alive and survive digestion. And if they do survive, it’s not certain they
will colonize the intestines in sufficient numbers to have most of the
proposed benefits. Some manufacturers claim to use processes that ensure
that the bacteria stay alive and have therapeutic effects, but very few
products undergo independent verification. Recent testing by ConsumerLab.com
of 29 probiotic products found that while all contained at least one billion
organisms per daily dose (“an amount that may provide some benefit”), a few
had far lower amounts than claimed on the label…
Bottom line: Probiotics are a promising field of
research and may one day be used to treat or help prevent many disorders.
But there’s not enough solid evidence to recommend their widespread use.
Larger, longer studies are needed to test specific
strains against specific conditions and to determine the proper doses and
regimens. The FDA has not approved any specific health claims for
probiotics and has called claims made by some manufacturers, including
yogurt companies, misleading. Going one step further, the European Union
recently deemed that any reference to the term “probiotics” on packaging is
unauthorized and subject to legal action.
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