But a strong immune system is built on good nutrition – and our knowledge of the key dietary elements that support a powerful immune system has expanded greatly in the last few years.
In addition to a diet rich in fruits, vegetables and whole grains, the following four nutrients have been shown to be powerful immune enhancers.
Vitamin D – activating natural killer cells
Depletion of Vitamin D in the body has already been identified as a key contributory factor to the common problems of osteoporosis and osteopenia (loss of bone density). More recently, D depletion has also been shown to reduce the effectiveness of the innate immune system – the first line of defence against bacterial and viral invaders.
A gene named Vitamin D3-Upregulated Protein 1 (VDUP1) takes a vital part in giving directions to stem cells to expand into natural killer cells, one of the key elements in the innate immune system, and whose function is to seek and destroy virus-infected cells.
If you are low in vitamin D, fewer numbers of natural killer cells are formed and your innate immune defence against viruses becomes impaired. Since the other function of natural killer cells is to kill tumour cells, D-depletion also increases our risk of cancer.
Selenium deficiency in the body weakens resistance to invading viruses
Selenium deficiency allows invading viruses to mutate and remain for a longer period in the host. Researchers at the University of North Carolina compared mice that received a selenium-deficient diet with non-deficient animals, all of which were exposed to the human influenza virus. The deficient mice had more severe cases of the flu and it lasted for a longer period of time than the non-deficient mice.
Selenium deficiency has become a prominent dietary factor contributing to an increased risk of infection, and in the worst cases, death. It is prevalent in large parts of the world, including the UK.
Beta sitosterol – an important immune modulator
The nutritional plant extract beta sitosterol is one example of a group of molecules called sterols. They are regarded as the plant kingdom’s equivalent of cholesterol. Beta sitosterol is a natural immuno-modulator as it up-regulates (enhances) certain aspects of immune function while down-regulating others. It is present in a number of plant foods and especially seeds and nuts.
Beta sitosterol increases natural killer cell activity, so depletion leaves the cells under-active. This contributes to an overall degradation of the innate immune system. Hence, a diet rich in sterols can ‘quieten’ auto-immune responses and improve immune response.
1-3, 1-6 Beta Glucans – priming the immune system
Of all the natural compounds known to stimulate the innate immune system, the best documented and most effective are the 1-3, 1-6 beta glucans, generally derived from brewer’s yeast and now available as a supplement.
1-3, 1-6 beta glucans are reported to be highly effective antioxidants but it is their role in activating the immune system that has attracted the most recent medical attention.
When you ingest 1-3, 1-6 beta glucans, receptors on macrophages - which are important components of the body’s innate immune system – recognize the beta glucan particles as foreign bodies and ‘assume’ that a potential enemy has arrived. In response, the number and activity level of the body’s immune cells is increased.
Many well-conducted research papers have shown that this sequence results in a significant enhancement of resistance to infection – so it is worth examining how this nutrient works in a little more detail.
A biological ‘guided missile’
Biothera is a world leader in research on beta glucans, and is the manufacturer of a patented source of 1-3, 1-6 beta glucans, WGP 3-6. Their research shows that, once swallowed, 1-3, 1-6 beta glucans pass through the stomach into the small intestine and are taken up by specialized regions called the Peyer’s patches.
In the Peyer’s patches, the beta glucan molecules are encountered by circulating macrophages – immune cells whose function is to engulf and digest pathogens – defined as foreign invaders, whether viral, bacterial or even cancer. (Macrophage literally means ‘big eater’.)
The macrophages break down the beta glucans into smaller particles and transport them to immune organs throughout the body. There the active fragments of beta glucans bind themselves onto the surface of the most abundant immune cells in the body – the neutrophils.
The binding of beta glucan fragments onto the surface of neutrophils ‘primes’ these immune cells and makes them ready to seek out and destroy pathogens. Once it encounters a pathogen, a neutrophil locks on to its surface and recognises it as ‘non-self’ i.e. foreign. It is now able to destroy that pathogen by releasing toxic chemicals.
But the neutrophil can only lock onto a pathogen when a specialised receptor on the pathogen’s surface is occupied by two elements – a blood protein called complement, and beta glucans - (the receptor is called Complement Receptor 3 or CR3)
The CR3 receptor is occupied naturally in the presence of some pathogens – e.g. fungal infections. But there are other threats, including many infectious diseases, viruses and cancer, where beta glucan is not present. Thus, by taking beta glucans, the neutrophils are provided with the missing element they need to function effectively as natural ‘guided missile’ killer cells.
But there is another, secondary benefit. As the pathogen is destroyed, a different group of killer cells retains fragments of that pathogen on their surfaces. They now become memory cells and part of the acquired immune system.
These memory cells are now able to recognize the virus or pathogen should it attack a second time and will produce antibodies which stick to the surface of the virus and prevent it from infecting healthy cells.
Who should take beta glucan?
Extensive research shows that beta glucans can be taken by anyone wanting to maintain or enhance the effectiveness of their immune system. That includes anyone who experiences daily stress (which lowers the immune response), together with people who are at risk of infectious diseases, are exposed to pollutants or experiencing slow and incomplete healing. Amateur and professional athletes may also derive benefits from beta glucan, since intensive training can actually lower the immune response.
Additional circumstances for use would include people entering hospital - who are at greater risk of infection – as are long distance air travelers, who are exposed to a higher levels of radiation. (Indeed the US Government are now testing Biothera’s beta glucans with a view to stockpiling it as a protective measure against the possibility of nuclear radiation).
Ideally, beta glucan should be taken as a daily supplement in periods of stress or threat, because the immune system’s viability fluctuates from day to day and the life cycle of neutrophils is short – less than 2/3 days.
Protect yourself naturally without side-effects
Since beta sitosterol and beta glucans are natural supplements derived from food, they are safe for people of all ages. Indeed food derived nutrients are, in principle, normally safer than artificially created pharmaceutical drug molecules, precisely because they are natural and have been consumed for centuries.
This cold and flu season, especially as there is a shortage of flu vaccine, it is worth considering this new way to enhance your immune system.
All natural & safe ImmunoShield
The role of beta sitosterol and 1-3, 1-6 beta glucans in strengthening the immune system is explained in detail by the international health expert Dr Paul Clayton in his book Health Defence and at www.drpaulclayton.com.
Dr Paul Clayton, who is a fellow of the Royal Society of Medicine and a former advisor to the UK Committee on the Safety of Medicines, advised on the formulation of Uni-Vite ImmunoShield, a natural nutritional immune system booster. It contains the unique combination of beta glucans supplied by Biothera and beta sitosterols, along with other essential nutrients.
Visit www.immunoshield.com to learn more about the effective use of these two important food ingredients in activating immunity. ImmunoShield also works synergistically with Uni-Vite’s NutriShield – a very comprehensive daily supplement.