We think of stress as psychological overload but there are many different forms of stress that act as ‘stressors,’ all of which can overload the body’s ability to stay in healthy balance. Stressors include everything from a poor diet and sedentary lifestyle, through to the chemical soup our bodies have to detoxify daily, including things we all commonly use, such as body care and household cleaning products, as well as polluted air and water supply and pesticides in non-organic food. Consequently, that ancient in-built defence (immune) mechanism is readily switched on to deal with the perceived ‘threat.’ This is more commonly known as the ‘fight or fight’ response.

Immune defence mechanisms evolved to be able to discriminate between what is ‘self’ and ‘non-self’ to prevent autoimmune-related issues. Even single-celled creatures demonstrated this capability. The immune system of modern man gradually developed into a highly complex system that could adapt rapidly to new dangers, new invaders (pathogens) and new situations. Alongside it, our stress response system was designed to detect and respond to acute danger signals that were a direct threat to our survival. Together, these physiological mechanisms gave us the adaptability that allowed our ancestors to explore the world and inhabit a multitude of different environments.

We detect danger through our five senses, these senses provide information about the world around us. When our senses perceive a threat, a cascade of physiological events are activated, commonly referred to as the ‘fight or flight’ response. In the past, many environmental danger signals would have carried an implied danger of injury and infection, so an immune response was needed too.

It has been discovered that the immune system and nervous system communicate with one another using a common chemical language. This allows the immune system to act as our ‘sixth sense’ and alert the nervous system to the presence of possible invaders or ‘pathogens’. Such pathogens cannot be detected via the usual five senses. Through its communication with the brain, the immune system can regulate behaviour in a way that is consistent with our survival.

An acute stress response in the face of danger activates the nervous, hormonal and immune systems. Just as in mankind’s early days, acute stressors still activate the sympathetic nervous system and hypothalamic-adrenal axis (the ‘adrenaline rush’) in order to increase energy to organs needed for direct survival – the brain for decision making, the heart to pump more blood, the immune system for protection and the muscles for physical action. Organs not immediately required for survival are temporarily ‘closed down’ to reduce their energy demand; for instance, our digestive system works less efficiently when we are in a stressful situation. description

When activated, the immune system produces a state of ‘inflammation.’ This triggers signalling across the blood-brain barrier to inform the brain there is an infection or impending threat of infection. Inflammation is the body’s way of defending itself, isolating and eliminating infection, removing damaged tissue and promoting healing. Inflammation also releases substances that act directly on the brain to produce ‘sickness behaviour’ – sleepiness, loss of appetite and becoming sedentary.

Sickness behaviour allows energy to be withheld from organs not involved in the survival response, and diverted instead to the innate immune system – the body’s first line of defence against an infectious challenge. The innate immune system response should last about 12-28 hours. If the immune challenge is not resolved, the adaptive immune system, the body’s second line of defence, takes over, producing a much more specific and targeted reaction to individual pathogens. This is a self-limiting response that ends after about 28 days. Inflammation is the natural process by which the immune system deals with an acute danger signal. Ancient stressors that directly affected our survival included hunger, thirst, cold, fear and violence. Fast forward half a million years and we see a very different picture. New stress signals arise from processed foods, sedentary lifestyles, environmental pollution and levels of psycho-emotional stress that would rarely have been a part of our early, tribal history.

So, how does the immune system, designed to respond to injury or acute infection in the short term, deal with ongoing worries about paying the mortgage, or social isolation, or high blood sugar and insulin levels from an overload of refined carbohydrates? Quite simply, it can’t! What we see instead is a slower brain-hormone-immune activation and a weakened immune response, because our body can’t resolve these 21st century stressors using our age-old mechanisms.

Because the immune system has no other means of meeting these new kinds of ongoing stress, it responds with inflammation. We can think of this chronic, low-grade inflammation as a smouldering fire, which can only be put out when the problems are solved. But the body is unable to produce the substances needed to mount a full inflammatory response that comes to a natural conclusion. The innate immune system also has a high demand for energy and nutrients. Even short-term, mild mental or social stress can increase the amount of energy needed by the brain by 12 per cent. So where does this energy come from? The only way an inflammatory response can be maintained longer than the maximum 28 days is if the immune system actively takes more energy from other body systems. To do so, it uses the same mechanism that evolved to keep our vital organs functioning during acute danger, by ‘closing down’ other non-vital organs. The thyroid gland, the body’s main regulator of energy metabolism, is able to down-regulate all other organs so that their energy can be re-allocated.

We can now see that the process of inflammation, so useful in one environment, becomes detrimental in another. It is the mechanism through which psycho-emotional stress produces sickness behaviour, memory changes, tiredness and depression, as well as chronic inflammatory diseases.

The longer low-grade inflammation persists, the more selfish the immune system becomes in demanding an ever greater share of the body’s energy, at the expense of all other organs and body systems. It has been suggested that the brain is selfish and will never relinquish its energy demand. But this is only true up to the point where the immune system takes over the priority. Stress inhibits pancreatic insulin production so that blood sugar remains high, ensuring a good supply for the brain. But now the immune system is able to down-regulate glucose transporter receptors at the blood-brain barrier, as well as in muscle and fat tissue to utilise more of the available glucose itself.

Hormones that also have an immune system function, such as leptin, insulin and cortisol, are diverted for the immune system’s use by various mechanisms, inducing resistance of the rest of the body’s organs to these hormones. Eventually, almost all neurotransmitters are also put at the service of the immune system and so are depleted from the rest of the body. This process is considered to mimic mammalian hibernation; it has been called non-permissive brain syndrome and essentially it is long-lasting sickness behaviour. It is present in diseases with disturbed brain function, such as Alzheimer’s disease, Parkinson’s disease, fibromyalgia syndrome, chronic fatigue syndrome and depression.

Adele practices in London and Brighton as well as managing a mobile MultiscanPro clinic. Adele has also been consulted as a nutrition expert for the London Sleep Centre in Harley Street – a leader in the provision of diagnostic and treatment services for people with sleep disorders and related medical and psychological conditions.

Following a previous career in the travel-retail industry, Adele’s client base extends as far Singapore and the US, where she also supports corporate clients. She is regularly consulted by professional bodies and associations to run international and UK-based exhibitions and practitioner training events and conferences, as well as to consult on the development of ‘food as medicine’ style menus (free from all major allergens), including The Institute for Functional Medicine (IFM), the Alliance for Natural Health International (ANH-Intl) and The British Association of Applied Nutrition & Nutritional Therapy (BANT).

In this capacity Adele has also been engaged by corporates and wellness/fitness operators to address consumer audiences on health and nutrition, including Wellness Academy, Beyond the Barriers, Mint Fitness and British Military Fitness. As a trained journalist and nutrition commentator, Adele has worked with the BBC and Sky Sports and written for numerous magazines and newspapers.