It is a general belief by most people that vitamins, herbs and nutrients can "strengthen the immune system." But what exactly does this mean? I will devote several sections on this website to making this more clear.
The body’s immune system is primarily responsible for protecting the body against foreign substances or organisms. To do this, it must distinguish between self and not-self. As currently understood, this complex system involves many, many organs, cells, systems and chemicals that help protect the body against infection and disease. This is done through both specific cellular immunity and other non-specific defense mechanisms. Non-specific immunity (also called natural immunity) developed first in our evolution, which may account for its less specific action. Some natural immunity cells, like Kupffer cells, remain primarily in the liver where they neutralize toxins of all sorts. Our much more specific cellular immunity developed later, and works like a well-trained detective squad which, after getting fingerprints and collecting crime scene evidence, identifies and arrests only specific, targeted criminals. In a strict scientific sense, only cellular immunity is called the immune system. However, for the purposes of this website, we will consider both specific and non-specific defensive mechanisms to be coordinated arms of the body's overall immune system.
In this sense, the immune system as a whole consists of the lymph system organs, the white blood cells, and various specialized cells and chemicals such as antibodies. Think of it as a large army with many soldiers, tanks, guns, planes, bombs, computers, and various other resources. Many serious diseases, including HIV, CFIDS, Candidiasis, Multiple Chemical Sensitivities (MCS), chronic viral infections, and cancer are characterized by chronic immune system dysfunction. Since time immemorial, herbal medicines have excelled at improving weak immune function, and toning down an overactive immune system. Our understanding of how and why this is true is advancing every day. The immune system is more than the cells and organs of which it consists. As always, it must be viewed in the context of the greater whole, and it depends like all other parts of the body, on food choices, digestion, exercise and mental attitude etc.
A Broad Understanding
In the simplest of simple understanding, the immune system can be overactive or underactive, in exact concordance with the ancient concepts of excess and deficiency. Immune deficiency states render us more susceptible to infections and tumors, and immune overactivity makes us vulnerable to unnecessary inflammation and tissue destruction. Another aspect of immune dysfunction is now being recognized in diseases such as amyloidosis, in which abnormal deposits of proteins from fragments of immunoglobulins appear in tissues. Recalling that one of the purposes of the classic divisions of Ayurveda is to help us recognize universal patterns within the whole, we can divide immune problems into three large categories for ease of understanding, broken into both positive and negative manifestations.
• Vata immune function - in the postive sense, the Vata part of the immune system is a well-regulated immune system, super sensitive to the slightest changes in overall healthy or outside influnces. In the negative sense, this refers to overall immune deficiency, where there is a failure to respond and regulate properly. Here it is often necessary to strengthen (nourish) or stimulate (wake up) immune and/or nervous system function, increasing immune cell numbers and activation.
• Pitta immune function - In the positive sense, the Pitta or catabolic part of the immune response is a fast, powerful and overwhelmingly aggressive response to microbes or toxins. In the negative sense it refers to immune overactivity, where there is a preponderance of destructive inflammation and heat. Here it is often necessary to calm (downregulate) immune function and reduce inflammatory chemicals, mediators and triggers.
• Kapha immune function - In the postive sense the Kapha or anabolic part of the immune response refers to various growth factors, debris removing and repair mechanisms that remove solid wastes and stimulate rebuilding of healthy tissue, such as nerve growth factors. In the negative sense it refers to immune-related problems where abnormal secretions, growths, deposits or plaques form quickly or over time. Here it is often necessary to reduce coagulation, break up stagnation and improve circulation.
This is just one way of many ways to think about the big picture. Having a global perspective such as this is important when trying to figure out treatments. Understanding the larger, more basic relationships allows one to see complex relationships that occur at different levels. For example it is well known in Ayurvedic medicine that when Pitta increases, Vata and Kapha tend to decrease. Ayurvedic doctors noticed this when patients with inflammatory diseases developed digestive problems and/or nervous-related symptoms and vice-versa.
It is now know that at the cellular level, proinflammatory cytokine chemicals (discussed below) "reprogram" metabolism, and are directly linked to altered nutrient uptake and utilization (Spurlock, 1997). In general, anabolic (Kapha) processes are interrupted or slowed, and catabolic (Pitta) activities are amplified. These observations have important clinical implications, and gave Ayurvedic practitioners philosophical "permission" to develop colon and digestive system treatments for seemingly unrelated inflammatory and nervous system problems eons ago. This cause is now being championed by researchers like Dr. Jeffrey Bland, author of the wonderful ground-breaking monthly tape series called “Functional Medicine Update”
Chinese medicine is another fountain of research on the use of herbs to regulate immune function. The major medical universites of China now offer college and graduate level courses in this subject, and admission to these programs is extremely coveted and limited to only those students who score the highest marks on the Chinese national exams. My wife, Dr Naixin Hu Tillotson, told me that getting into these programs is now as difficult as getting into Harvard or Yale in terms of competition, and more difficult in terms of hours of preparation and study required to pass the entrance examinations.