This article was originally published as a guest editor post at foodpharmacy.se
By: Graeme Jones, clinical physiologist and CEO at Nordic Clinic Stockholm.
The immune system is all over the news these days. Its antiviral functions get all the attention but there are good reasons to consider the entire immune system, with its full range of functions. Its condition is one of the most important factors determining health and disease overall. Now’s the time to appreciate the importance of nurturing our immune systems, not only to withstand acute infections but also some of the most dreaded diseases of the modern world.
The often ignored causes of autoimmune disease
While infections bring to mind runny noses, fevers and sore throats, you may be surprised to learn that they can cause a vast number of conditions. Autoimmune disease happens when the immune system attacks our own tissues by mistake. Researchers are well aware that autoimmune conditions like lupus (1), rheumatoid arthritis (2), multiple sclerosis (3), inflammatory bowel disease (4), thyroid disease (5), ankylosing spondylitis (6), OCD and PANDAS (7) and many more can be triggered by viruses, bacteria, fungi, or parasites (8). In other words, a well functioning anti-infectious immune system also protects us against autoimmune disease. Neuropsychiatric disorders such as autism, schizophrenia and psychosis, thought by some to have an autoimmune component, can also be triggered by infections, sometimes maternal infections while in the womb (9-12).
Uncontrolled immune cells can also take part in the development of autoimmune disorders, even when there seems to be no infection. This happens when failsafe mechanisms and built-in immune suppression don’t work, and when inflammation is too high which might result from any or several out of a wide range of lifestyle and environmental factors. (13)
Cancer – when immune function fails
Unknown to many, infections can cause cancer. It’s a well established fact that the human papillomavirus can cause cervical cancer, but this is not the only infection-cancer connection. In fact, examples are numerous. (14) Moreover, immune cells are normally able to recognise and destroy cancerous cells; tumor growth and metastases is what happens when they fail. Immunotherapy is already highly successful in treating some cancers. Immunotherapy means stimulating the immune system to enhance its inborn ability to detect and destroy cancerous cells. (15) However, an even more successful strategy might hypothetically be to optimise normal immune function, even before cancer grows and spreads.
Depression is caused by inflammation
Depression is highly associated with inflammation. There are many possible reasons we might be inflamed, and one of them is infection. When researchers inject lipopolysaccharides (bacterial toxins) into mice, or interferon gamma (a protein which helps the immune system deal with infections) into human study participants, mimicking an infection, the rodents and participants often develop symptoms of depression, and rather rapidly. (16, 17, 18)
A proinflammatory diet, sedentary lifestyle and excessive stress all increase inflammation as well, which affects the brain and the immune system: where there’s inflammation, the immune system is always involved one way or the other. (19)
ME/CFS – immune dysfunction in every sense
The devastating condition myalgic encephalomyelitis (often called chronic fatigue syndrome, or ME/CFS for short) has multiple potential causes but often starts with an infection. (20) Researchers have also observed immune dysfunction in these patients. Some of them fail to mount an appropriate immune response, meaning they have a hard time fighting off infections.
Does everything come down to the immune system in the end?
Even type 1 diabetes (21), IBS (22), Alzheimer’s disease (23), and cardiovascular disease (24) ‒ while multifactorial, of course ‒ have been connected to infection and/or to immune dysfunction. And when a clear infection isn’t involved in the pathogenic course, an imbalanced or overgrown gut flora is often implicated, which plays an intricate game with the immune system and may exert a central impact on the conditions listed above of a magnitude equal to infections.
That’s an impressive list of conditions, covering the majority of health conditions known to mankind.
To sum up, the anti-infectious and self-regulating operations of our immune system may be critical to protect ourselves from diseases that surround us every day. Diseases that dramatically decrease our quality of life, but may be preventable.
It all makes one wonder. Why do some people develop ME/CFS or lifelong autoimmune disorders from an infection that we’re supposed to be able to clear, or at least bounce back from once it’s been treated? What distinguishes those who catch every infection that comes along from those who sail through life with little more than the occasional bout of the sniffles? Why do cancerous tumours dissolve in some while they grow, and spread, in others?
I’m going to stick my neck out: if you have a well-functioning immune system, supported by a healthy lifestyle, most infections are not supposed to cause lifelong disease. The system is supposed to do its job and then sit right down again. If it does not, something is wrong, and the evidence that the status of our immune system means everything in terms of disease prevention mounts to levels that we can’t (and shouldn’t) ignore.
Genetic susceptibility does play some part (25), that much is undeniable. However, as we shall see in this seven part series, environmental, behavioural and lifestyle factors all have a massive impact on immune function.
This is paramount. The largest part of our health care budget is spent on pharmaceutical management of chronic disease. That strategy is expensive, ridden with side-effects and shockingly underwhelming in terms of health outcomes. By taking to heart that immune function and lifestyle choices are at the very centre of our well-being, and adapting medical interventions thereafter, we can free national economic resources so large that anyone would gasp at the insight.
So how you and I care for our immune systems affects not only our own quality of life, our happiness and longevity, but society as a whole.
In the upcoming article series I’ll guide you through the most important ways the immune system is strengthened or burdened, and how to adjust your lifestyle to help it work as well as it possibly can. I’ll address the profound effects of stress, sleep, physical activity and diet on immune function. Furthermore, we’ll learn about the surprising links between joy, humour, sun exposure, gut flora and optimal immune health.
The good news is that most interventions are free of both cost and side effects. By reversing chronic disease or reducing its likelihood, you also reduce your own expenses for medication, doctor’s visits and sick leave. This is what’s known as a “win-win-win situation”. We all win – your health and happiness, your wallet and your fellow human beings.
So for yourself, your neighbour, your king and country – tend to your immune system!
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