How to Strengthen Your Immune System Naturally

This Topic Covers:  A through understanding of how the immune system works;  Information that will disclose methods to sustain your health, methods to place you on the road to recovery, and information that will address and combat attacks on your health.  The topics and treatment plans in nutritional, vitamin, mineral, herbal and essential oils also address these areas. 

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Using Your Immune System to Stay Well

"The strength of our immune system is what makes the difference between who gets sick and who doesn't. The one with the immune system functioning below base-line normal has an increased risk of getting sick," says Woodson Merrell, MD, director of integrative medicine at Beth Israel Medical Center in New York City.

But is there anything you can do to keep your immune system from dropping below par -- or increase its activity if it does? Doctors say yes. And the secrets lie in understanding a bit about how the immune system works -- and how your everyday life can stoke the fires of protection.

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.

"This entire system is known as the 'humoral' response. It's your body's innate ability to manufacture antibodies that counter the infectious particle -- allowing your body to eradicate it," says Phillip Tierno Jr., PhD. He's director of clinical microbiology and diagnostic immunology at Tisch Hospital, New York University Medical Center, and author of The Secret Life of Germs.

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.

"Your body recognizes that pathogen again, and immediately calls up the memory of the previous infection and sets out to destroy the invader before the disease develops," says neurophysiologist Carl J. Charnetski, PhD. Charnetski is a professor of psychology at Wilkes University in Wilkes-Barre, Pa., and co-author of Feeling Good Is Good For You: How Pleasure Can Boost Your Immune System and Lengthen Your Life."

"The most important thing you can do for your immune system is to achieve lifestyle balance and adopt the fundamentals of healthy living. This will give your immune system what it needs to function at optimal capacity," says Merrell.

Reference Source - - Life Extension Foundation

  • The immune system declines as we age, making us more susceptible to various diseases and pathogens.

  • The immune system's health is closely related to stress, frequency of exercise, and nutritional status. Poor intake of vital nutrients is closely associated with a depressed immune response and an increased rate of disease.

  • The immune system has two primary defense mechanisms: natural, which uses white blood cells and physical barriers to protect us from disease, and acquired, in which specialized cells generate antibodies to defend against specific pathogens.

  • Inflammation is caused by multiple factors, including microorganisms, physical stress, tissue death, and inappropriate immune responses. Chronic inflammation is linked to diseases such as heart disease. Inflammation is mediated by cytokines and free radicals. It is an important immune system response, but it can also be dangerous because a chronic inflammatory state is linked to various diseases of aging.

  • Free radicals are unstable molecules that readily react with other molecules, especially oxygen, to change their chemical composition. Antioxidants are used by the body to scavenge for free radicals and limit the amount of damage they can cause.


The Purpose of the Immune System

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


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.


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)

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.


Mounting an Immune Response  


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.


Infection and Disease of the Immune System

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. -  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.


Vaccines When Your Immune System Is Compromised

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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.


Types of Vaccines

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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.


Signs of Immunodeficiency Disorder  

Your doctor might think you have an immunodeficiency disorder if you have:

  • Infections that keep coming back or do not go away

  • Severe infection from bacteria or other germs that do not usually cause severe infection

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) - Copyright 2014 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.


Nutrition, Immunity, and Your Genes

Reference Source -


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).


Foods That Boost Your Immune System

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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.


Restoring the Immunity Naturally 

Reference Source -

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.


Supporting a Healthy Immune System

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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). - Copyright 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 -

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. -  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 -


The Role of Nutrition, Exercise and Stress - - 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. - 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.


The Gut and Your Immune System

Reference Source -  - 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 -

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.


Maintaining Gut Health - 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.


Probiotic Immune Therapy - 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. - 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:

  • Treating symptoms of irritable bowel syndrome

  • Treating vaginitis

  • Treating diarrhea caused by C. difficile bacteria

  • Treating Crohn's disease

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 -

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 -

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 - 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 -

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. -  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 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.