The mainstream media has offered plenty of advice to the public for the treatment of influenza through the use of antiviral drugs and flu vaccines. However, there has been little or no mention about preventive measures people can take to boost their immune systems with supplements, which could help to ward off the possibility of infection.
In addition to the annual flu pandemic, the world we live in today is also becoming more toxic. The air we breathe is more polluted, the foods we eat are sprayed with pesticides and resistance to antibiotics is becoming a concern. Furthermore, there is also the very real threat of bioterrorism knocking on our door. These factors have made the topic of immunity an important one. From colostrum to herbs to vitamins and minerals, the immune support market has only begun to hit the radar screen and has tremendous opportunities for growth.
Understanding Immunity
The human immune system forms a complex constellation of responses to attacks from outside the body. Its main purpose is to defend against millions of bacteria, microbes, viruses, toxins and parasites in order to protect the body against disease. To understand the power of the immune system, just imagine what happens to any living creature once it dies. In a matter of hours foreign invaders begin to take apart the body until all that is left is a skeleton. Although this is an extreme example, it conveys the mighty force of the immune system and what happens when it shuts down.
According to Don Cox, business development manager-Food & Ingredients, SiberHegner North America, Baltimore, MD, a healthy immune system is primed to respond to an infection. "The important elements of a healthy immune system include healthy bone marrow and a functioning thymus, spleen and lymph nodes," he said. "These basic components of the immune system serve to produce immune cells and provide the necessary differentiation of the cells into the many types that support a healthy immune system."
Explaining the two types of immunity was Patrick Geals, general manager, Fonterra Health & Nutritional Solutions, Auckland, New Zealand. "Our first line of defense is innate immunity, which is present when we are born and provides protection against most harmful microbes," he said. "Our second line of defense is adaptive immunity, which is also known as acquired immunity. Adaptive immunity develops as we grow through exposure to invading microbes that have managed to break through the innate immune defenses."
Describing the immune system another way was Brien Quirk, technical director, Draco Natural Products, San Jose, CA, who said that it represents the body's control system when it is functioning properly. "The immune system maintains the boundary between self and non-self by destroying any invader or tissue that has become abnormal, such as cancer or virus infected cells," he said.
In addition, he said that the immune system also governs many other processes such as cell growth, inflammation, cell death and energy production through a complex system of chemical messengers known as cytokines. "A healthy immune system has a complex array of cells," he explained. "Most originate in the bone marrow and then migrate outward, while others are fixed in tissues and organs such as the spleen, liver and lymphoid tissues. The common cells of the immune system are monocytes, eosinophils, neutrophils, basophils, T and B lymphocytes, natural killer (NK) cells, cytotoxic killer cells and macrophages, which travel out of the blood stream and into tissues."
Going into even more detail was Linda Douglas, manager of scientific affairs, GTC Nutrition Company, Golden, CO. "The immune system is the body's first line of defense and consists of very specialized cells and a separate circulatory system that responds to fight infection in the body. It also interacts with the circulatory system, which handles the body's blood," she said. "The immune system employs special organs, known as lymphatic vessels, lymph nodes and lymph organs, including tonsils, adenoids, Peyer's patches in the intestine, bone marrow, the spleen, thymus and appendix. The tissues of the body are bathed in a clear fluid called lymph, which contains white blood cells, or the lymphocytes. The lymphocytes are active agents that fight against foreign bacteria, proteins or other invaders."
In addition to the lymphocytes, Ms. Douglas said the immune system also works through the B cells from bone marrow and the T cells from the thymus gland. "These cells produce antibodies that can recognize specific antigens and act as a targeting mechanism for their removal," she said. "B cells mark invading cells for destruction, while T cells mark and destroy diseased or invading cells. The T cells also coordinate and orchestrate other immune cells and overall immunity."
Immune System Breakdown
There are countless reasons why the immune system might breakdown. Most experts agree that leading causes include improper or poor nutrition and stress.
Lori Siegler, marketing manager, Larex, Inc., White Bear Lake, MN, discussed these compromising factors. "These issues (stress, environment, poor diet) all have the ability to depress the immune system and reduce resistance," she said, adding, "We can optimize our immune function by increasing beneficial cell populations through our diet so that the host is better able to handle immune stressors." However, she said, the immune system is very complex and balancing all of the components can be a challenge.
Angie Strotman, marketing manager, Proliant Health Ingredients, Ankeny, IA, offered her perspective. "Most of us don't respect the dynamic nature of the immune system. Breakdowns can occur at all levels of protection," she said. "Stress can suppress the activity of the immune system in just a few hours. Dehydration and poor nutrition, such as vitamin A, zinc or iron deficiencies, are all known to reduce the effectiveness of the mucosal barriers. In addition, lack of rest, poor dieting and exhaustive lifestyles can all contribute to lower humoral and cell-mediated immunity."
Draco's Mr. Quirk said the primary factor that suppresses a healthy immune system is the stress hormone cortisol, which is released during times of physical or emotional stress, pain, insomnia, poor glycemic control, drug use and excessive sugar and caffeine intake. Further, he said, "Malnutrition of many essential nutrients and protein is a key factor in a depressed immune system. The seriousness of this is that it can lead to the immune system's inability to properly recognize and destroy cells that become cancerous." He continued, "The immune system can also begin to turn on itself and attack tissues of the body, such is the case in conditions like lupus and rheumatoid arthritis. In less serious cases, people may just be more susceptible to colds, flu, skin infections, fatigue and gum disease."
Expanding on Mr. Quirk's explanantion of autoimmunity was Fonterra's Mr. Geales, who described it as a situation when the body's immune system fails to recognize its own normal body tissues and attacks and destroys them as if they were foreign. "It is thought to be triggered by exposure to certain microbes or medicines, especially in genetically predisposed people," he said. "A single body organ or multiple organs may be affected."
Examining Market Trends
The immune support market is still in its infant stages. As a category, it is slowly but surely gaining recognition among consumers, however, in order for the category to continue to grow, most experts agree that education and science are required to lead the charge.
Fonterra's Mr. Geales, who said the global market for immune-related disorders is currently estimated to be $66 billion, shared his thoughts on awareness and research. "There is wider awareness of general health and wellness products, which are the bulk of what makes up natural immune supplements available on the market," he said. "Consumers are becoming more and more aware of their own health and nutrition and are looking for a means of preserving it or preventing themselves from getting an illness or disease. As a result, they are looking for convenient and safe products to take. It is very important to develop not only new products but to invest in research to ensure that the product is effective."
Proliant's Ms. Strotman also offered her perspective on awareness and education. "Consumers recognize very few products for immune support, with the most recognizable being vitamin C," she said. "The immune market has tremendous opportunity for growth, however, I believe in order for the market to continue to grow successfully there will need to be heavy promotion and education."
GTC's Ms. Douglas said that increasingly active lifestyles and greater awareness of disease prevention causes consumers to find products that prevent illness. "As with any fortifying ingredients, there are two classes of consumers," she explained. "First are those that actively seek immune-boosting ingredients, usually via supplements or medicinal foods. The larger group includes those that do not actively seek a fortified product, but are enticed by label communications that tout immune-boosting properties. The latter type will generally choose a fortified product over a non-fortified product when the option is realized, especially if the price is comparable," she said. "However, consumers will only make a repeat purchase if a product provides the same level of sensorial satisfaction as the non-fortified product. This is because passive health conscious consumers value the experience above the immunity boost. Therefore, label communications are highly valuable."
Discussing recent developments with echinacea was Draco's Mr. Quirk. "There is probably greater skepticism currently with the failure of some studies to validate the effectiveness of some echinacea preparations," he said. "In the future, it will be contingent upon the manufacturer to support claims with studies to ensure good sales and convince the general public of the quality and effectiveness of a product," he offered.
Another trend pointed out by Larex's Ms. Siegler is that companies are now marketing immune enhancement products for year round use and not just as seasonal items. In addition, she said formulators are looking for ingredients that have regulatory approval from FDA and which can be delivered in a variety of forms such as dietary supplements and foods. "Immune health has grown to be one of the top consumer product categories," she said. "The immune market will continue to grow as companies validate their ingredients with clinical studies, which will aid in customer acceptance."
Immune Support Ingredients
Vitamin C. Vitamin C has been widely studied for its antioxidant activity and is the ingredient with which consumers are most familiar when it comes to cold and flu prevention. While vitamin C has a long and popular history of use for its immune-boostingproperties, there exists research, which questions these benefits.
According to Herbert Woolf, scientific affairs manager, Human Nutrition, BASF, Mt. Olive, NJ, vitamin C has proven to be effective in supporting a wide array of metabolic functions, however, its role in relation to immunity is not as clear. "While there are many good examples of disease prevention or amelioration with proper nutrition, the use of vitamin C seems to be more closely related to other metabolic functions rather than direct immune response stimulation," he said. "Nevertheless, it is quite possible that the relationship does exist as it does for vitamin E, which has been well established."
In The Immune System Cure, authors Lorna Vanderhaeghe and Patrick Bouic say that vitamin C provides protection against viral infection by strengthening connective tissue and neutralizing toxic substances released by phagocytes. "Its direct antiviral action appears to be through the suppression of virus replication and the annihilation of virus-infected cells. Research confirms that vitamin C is antiviral, antibacterial and anticancer," the authors said. "It is known that PGE1, a prostaglandin that plays a major role in regulating T cell function, is enhanced by vitamin C. Vitamin C enhances one of the complement enzymes, C1 esterase, without which the entire enzymatic cascade of complement would not occur and non-self cells would not be destroyed. Tests show that taking as little as 1200 mg of vitamin C per day increased T cell activity, while 500 mg per day increased glutathione levels by 50%. Glutathione is extremely important to immune function becuase it eliminates toxic substances from the body, enhances cellular oxygen and activates enzymatic reactions."
A recent study conducted by Zila Nutraceuticals, Prescott, AZ, on residents of the small town of Mount Healthy, OH, supports the immune-enhancing properties of vitamin C. Over the course of 50 days, more than 400 residents agreed to supplement their regular diets twice daily with 500 mg of Ester-C, the company's patented form of vitamin C, which contains non-acidic mineral ascorbates and natural metabolites. At the end of the study, which was conducted during the winter season, 74% of the residents reported no symptoms commonly associated with colds, while 62% reported feeling healthy and vital.
Zinc. Zinc is another popular immune-boosting supplement that has been gaining ground for its role in combating the common cold and flu. According to InterHealth Nutraceuticals, Benicia, CA, which supplies L-OptiZinc, a patented L-methionine-bound zinc ingredient, zinc is essential for proper immune function because of its free radical scavenging activity. Like the antioxidant vitamins C, E and beta-carotene, zinc helps eliminate already existing free radicals and helps to prevent new ones from forming. As an essential part of superoxide dismutase (SOD), the company said zinc protects vital biomolecules called sulfhydryl compounds from oxidizing and turning into free radicals. In addition, the company said zinc competes with pro-oxidant metals iron and copper for binding sites, decreasing their ability to form free radicals.
According to The Immune System Cure, zinc is the most important mineral to the thymus gland, which orchestrates the immune function in the human body. "Zinc deficiency causes a reduction in T cells, NK cells and thymic hormone," the authors said. "Supplementation with zinc increases the ability of macrophages to digest invaders, dead cells and other debris, and enhances the ability of the immune system to eliminate bacteria."
Beta glucan. Beta-1,3-D glucan, a simple polysaccharide (sugar/carbohydrate molecule) extracted from the cell wall of common baker's yeast, has gained a reputation over the years for activating a powerful immune system response because of specific receptor sites for the beta-1,3-D glucan molecule that match a site on the surface of the macrophage, which is the first line of defense in the immune system.
In Activate Your Immune System, authors Leonid Ber and Karolyn Gazella said that when the macrophage encounters the beta glucan molecule, it becomes activated. "This triggers all the macrophage's powerful immune-stimulating capabilities. The macrophage serves many important functions, including the eating of antigens and cellular debris, and communicating with the T cells to tag antigens in preparation for future attacks," the authors said. "In addition, the macrophage stimulates bone marrow production of immune-supporting substances."
In addition to yeast, beta glucan is now being extracted from other sources such as barley, oats and other grains. Commenting on oat beta glucan was GTC's Ms. Douglas. "Beta glucan from oats is a soluble, viscous fiber found in the bran layer of the grain. Studies have demonstrated oat beta glucan's ability to stimulate the function or secretion of various immunoglobulins and immune system cells, both in vitro and in vivo," she said. "Researchers have concluded that oat beta glucan appears to up-regulate immune mechanisms and enhance resistance to some pathogens, and also has exhibited anti-tumor effects. This type of research is developing and is very promising at this time."
Immunoglobulins. According to Proliant's Ms. Strotman, immunoglobulins, which are also known as antibodies, are specialized soluble proteins produced by the immune system to provide specific protections against various pathogens, toxins, food antigens and other substances that can affect human health. Historically, she said, immunoglobulins have been consumed at very low levels through milk or colostrums. "Antibodies were discovered in the early 1900's, so the role of immunoglobulin in providing immunity is well known. Immunoglobulins are both circulated in plasma and secreted onto the body's mucosal surfaces, providing both systemic and mucosal protection," she explained. "The critical role of the immune system in the gut is often overlooked. The gastrointestinal (GI) tract is the largest exposed body surface and five to 10 grams of immunoglobulin, as secretory IgA, are produced daily to protect against the multitude of microbial challenges encountered there."
Discussing immunoglobulins further, Ms. Strotman said that the benefits immunoglobulins offer when given orally is not well known. This, she said, is one reason why the marketplace for immunoglobulins is relatively small. "The common dogma held by many in the scientific community on the oral administration of immunoglobulins is that the antibodies will be broken down during digestion, which would render them ineffective," she said. "However, more than a dozen studies in humans and animals have proven that this is not the case."
Arabinogalactan. Larch arabinogalactan (AG) is a naturally occurring, water-soluble polysaccharide found in high concentrations in the Larix genus of trees. "Larch AG has been shown to have a positive impact on the human immune system. It modulates the beneficial cell populations associated with immune function," Larex's Ms. Siegler said. "Arabinogalactan has been demonstrated in-vivo to increase or modulate levels of immune system white blood cells, specifically monocytes/macrophages, NK cell activity and properidin."
In addition, Ms. Siegler said, "In vitro cell studies have demonstrated that AG is one of the active immune compounds in echinacea. In fact, Larix AG-being a concentrated for of AG-modulates the human immune system better than echinacea."
Colostrum. Colostrum is the first milk secreted after partuition and has been used for centuries for antibiotic purposes to improve immune function, for treating rheumatoid arthritis and for general well being, according to Fonterra's Mr. Geals. "Recently, colostrum has been investigated as an immunological agent for its ability to reduce the effects of gastrointestinal infection, especially in individuals who are immuno-compromised," he said.
Mr. Geals said that the Fonterra's colostrum is sourced from the first four milkings (48 hours) after calf birth. "The composition of colostrum and its physical properties are quite different from that of mature milk," he explained. "The major difference between colostrum and mature milk is that colostrum contains higher levels of naturally occurring bioactive components. These bioactive components, including immunogloblulins, growth factors, lactoferrin, lysozyme and lactoperoxidase, provide colostrum with unique benefits, which are significantly different from those associated with mature milk."
Astragalus. Astragalus is an herb that is touted for its immune enhancing properties though, according to Draco's Mr. Quirk, it is unrecognized in many ways because it is often overshadowed by the more popular echinacea.
"Astragalus membranaceus is known in China as Huang Qi, which means yellow leader because the root is off-white yellow in color, and Qi refers to vital energy," explained Mr. Quirk. "It plays a prominent role in maintaining the health of the body."
Mr. Quirk discussed further the herb's role in supporting immune function. "Astragalus is a key immune tonic herb because it is thought to boost the wei chi, or the protective nature of the vital energy that helps repel pathogens," he said. "From a western scientific point of view this would translate to its ability to increase interferon, or secetory IgA, and IgG immunoglobulins in the mucous membranes that line the digestive and respiratory tracts. These immune proteins can directly bind to and inactivate viruses and pathogens. One study has shown that astragalus can increase by five- to six-fold the cytotoxicity of NK cells against target cells when treated with an extract of astragalus." In addition, Mr. Quirk said that the herbal extract has been shown to double cell life span and increase metabolic activity, lending support to its vital energy promoting effect and its ability to boost immune response. In terms of research, Mr. Quirk said, one study of 1000 human subjects given an extract of astragalus both orally and intranasally showed there was an effective preventative effect against the common cold.