Allergies are on the rise, affecting millions in the UK—but did you know your nervous system plays a key role? Research shows a strong connection between the immune and nervous systems, shedding new light on allergy management and treatment possibilities.

Read on to explore more from Caroline about the fascinating link between allergies and the nervous system—and how addressing nervous system regulation could play a role in allergy relief.

Allergies seem to be on the rise and according to Allergy UK, in 2024, an estimated 21 million in the UK are living with allergies. [1].  Allergies can affect different body systems (most frequently respiratory, digestive and skin) or systemically (in the case of anaphylaxis) and can be triggered from a variety of allergens from pollen to certain food types to venom/stings.

Allergies are typically thought of as solely an immune system problem; an over-reaction of the immune system to stimuli that ordinarily would not be considered harmful. Increasingly, however, it is being recognised that there is a cross-link between the immune system and the nervous system. Both are vital in maintaining homeostasis in the body and they work collaboratively (rather than independently). Kadowaki et al (2022) [2] emphasised this when they stated that “Importantly, the immune system and nervous system do not operate separately”. Undem and Taylor-Clark (2014) [3] state that “….allergy can be characterised as an immune-neuronal disorder” and in the case of food allergies Houghton et al (2024) [4] describe the occurrence of a “bidirectional communication between mast cells and neurons” (mast cells being white blood cells of the immune system and neurons being nerve cells of the nervous system).

Some symptoms experienced in allergic reactions, such as the sneezing reflex, are more obvious examples of nervous system involvement, but others might be less so. It is seen most dramatically in anaphylaxis wherein the sudden drop in blood pressure (which results in deoxygenation of tissues due to insufficient blood flow) and drop in body temperature have been shown by Bao et al (2023) [5] to be directly related to nervous system involvement.

Recognition of nervous system involvement in allergic reactions offers a potential new avenue of treatment (rather than relying on anti-histamines and EpiPens) within mainstream medicine. Currently it’s experimental, but in cases involving food allergies vagus nerve stimulation has been shown to significantly reduce mast cell numbers in the duodenum and the extent to which those that are there degranulate (release histamine and other chemical compounds) [4]. Other approaches include vagotomy (surgical procedure to remove part of vagus nerve in the abdomen) to prevent anaphylaxis [4].

Stress and Anxiety

There is an increased incidence of anxiety seen in those with food allergies (when compared with healthy individuals or those with other dietary related health conditions such as diabetes) [6] . It could be worth those experiencing anxiety considering if there is an underlying food allergy component involved. The body is complex so it’s good to take a holistic approach when viewing symptoms and to consider all factors.

Whilst stress doesn’t cause allergies, it has been shown to exacerbate them [7], so for those with allergies stress management could be useful in helping to reduce the extent of the symptoms.

The interaction of the nervous system with other systems of the body is fascinating, intricate and extensive. If you are interested in optimising your nervous system regulation you may wish to consider nervous system regulation consultations. Available at The Vale Practice, see www.hornbeamholistichealth.uk for more details.

Written by Caroline Heatlie (Chartered Physiotherapist and Holistic Health Practitioner)