Yoga, is an ancient mind-body practice that originated in India around 5000 BCE. While its positive impact on health and wellbeing, has been widely accepted, it is only relatively recently, that we have the scientific evidence to support its benefits. Of course, for most people practising yoga, it comes as no surprise that yoga is good for you. As a scientist, I find it reassuring to be able to explain why.
There is now a wealth of research supporting yoga’s benefits for stress and wellbeing. Just recently, there was interest in the media about the benefit of yoga on the immune system. This was following a report from the American Society of Clinical Oncology, recommending yoga for cancer survivors.
“Clinicians should consider prescribing yoga for survivors experiencing inflammation, which may lead to [. . .] increased risk of progression, recurrence and second cancers.”
This led me to explore some of the science. A recent review of yoga studies (2022) found that yoga practice had a beneficial impact on reducing inflammation.
The science details for those who are interested….
They examined the impact of yoga practice on inflammation, by looking at inflammatory markers. They found strong evidence for the benefits of yoga on the levels of circulating cortisol and classical inflammatory markers, such as C-reactive protein and cytokines such as interleukin-1 beta, interleukin 6, tumour necrosis factor-alpha and interferon-gamma. They also found supporting evidence for some of the less well studied makers, such as telomerase activity, beta-endorphins, Immunoglobulin A and brain-derived neurotrophic factor.
To ‘unpick’ why this is both exciting and encouraging, it helps to take a look at how the immune system functions, the role of inflammation and the consequences of dysregulation.
The Immune System
The role of the immune system is to protect us from ‘invading’ pathogens, such as bacteria, viruses and fungi, as well as recognising and removing harmful substances, including damaged or malfunctioning cells e.g. cancer cells.
There are two main branches of the immune system
1. Innate – our natural immunity
This is our first line of defence and consists of physical barriers, such as skin, and chemical barriers (sweat, tears, saliva, mucus, stomach acid) to stop harmful materials entering the body, as well as white blood cells, which ‘patrol’ checking for foreign or harmful substances. This is a quick and non-specific response.
The white cells involved in innate immunity are mainly ‘phagocytic’ which means ‘Pac-man’ like they ingest any foreign or harmful substance. Some white cells will ‘kill’, while others act as an ‘alarm’ system and release chemicals, such as cytokines to trigger an immune response, including inflammation. This ‘triggering’ may involve presenting antigens, to cells of the adaptive immune system. Effectively, acting as a ‘bridge’ between the innate and adaptive system.
2. Adaptive – acquired immunity
The adaptive immune response takes a lot longer than the innate immune response. Taking days and sometimes weeks to become properly established. It is based on specifically recognising antigens and responding.
T-cells and B-cells are responsible for adaptive immunity. Activated B cells produce antibodies and memory B cells circulate in the bloodstream offering future protection, in case the same pathogen is encountered. T-cells recognise antigens, which are ‘presented’ by other immune cells, and can then destroy these infected cells.
The role of the adaptive immune system is essentially for enhanced protection, preparing the body for future challenges. It is through this system that vaccinations work.
Inflammation is a natural part of the healing process, it is generally to protect us, however, if prolonged or inappropriately ‘triggered’ it can cause problems, from pain to autoimmune disease. Chronic conditions associated with prolonged inflammation are cancer, heart disease, diabetes, asthma and Alzheimer’s.
Stages of Inflammation
This is caused by infection or tissue damage
2. Identification by inflammatory sensors (Pattern recognition receptors)
The pathogen or damage is recognised and ‘alarm’ signals are sent to initiate the production of inflammatory mediators.
Cytokines act as ‘messengers’ signalling an immune response
The appropriate immune response clears infection and repairs any damage
Cytokines (small secreted proteins) are the key modulators of inflammation. They can be seen as the communication system to signal whether things are functioning normally or to alert that there is damage, an injury, or an invasion and a defence response is required. As with many metabolic responses, the immune response relies on a feedback loop system to bring the body back into homeostasis (balance) once the infection or damage has been resolved. If there are any functional alterations in the sensors or mediators this can disrupt the homeostatic set point or the feedback loop. If the stimulus, activating the inflammatory response is not properly dealt with, that homeostatic disruption continues to trigger pro-inflammatory events. Over time, a failure to reset homeostasis creates a low grade chronic inflammation. This dysregulation resulting in a continued inflammatory response, has been linked to chronic pain, obesity, type 2 diabetes, atherosclerosis, neurodegenerative disease and cancer.
The major cytokines, Interleukin -1 beta, Interleukin 6 and Tumour necrosis factor, which can be measured in the blood, have been implicated in chronic low grade inflammation and neuro-inflammation. These pro-inflammatory markers have been shown in scientific studies to be reduced in individuals practising yoga. It is this observation, indicating that yoga is beneficial for a healthy immune response, that has led to the recommendation of yoga for those individuals experiencing inflammation.
Maintaining a Healthy Immune system
Clearly, a good healthy immune system is required to be able to protect us against ‘invading’ pathogens and recognise harmful substances or fight potentially disease-causing changes in the body such as cancer.
It is important for all of us, and particularly as we age (See Part 2 – Inflammageing) to look after our immune system. There are a number of things that we can do to maintain a healthy immune system and keep inflammation in check.
- Eating well – A healthy diet and maintaining a healthy weight
- Exercising regularly
- Moderate alcohol intake
- Adequate sleep
- Minimising stress
At Mindlab, we offer yoga, mindfulness and clinical hypnotherapy. They have all been shown to reduce stress and improve sleep, which impact on the health of our immune system. Furthermore, scientific research has shown that yoga and mindfulness reduce pro-inflammatory markers and improve immune function.
If you are interested in making any changes to benefit your health and wellbeing, why not contact us and see how we can help you?
Davidson R.J., Kabat-Zinn J. et al. (2003) Alterations in Brain and Immune Function Produced by Mindfulness Meditation Psychosomatic Medicine 65:564–570
Desikachar K., Bragdon L., Bossart C. (2008) The yoga of healing: exploring yoga’s holistic model for health and wellbeing. Inter J. Yoga Therapy 15, 17–39
Dunn T.J. and Dimolareva M. (2022) The effects of mindfulness-based interventions on immunity related biomarkers: a comprehensive meta-analysis of randomised controlled trials. Clinical Psychology Review 92, 102124
Estevao C. (2022) The role of yoga in inflammatory markers. Brain, Behaviour & Immunity – Health 20, 100421
The Times, 7th June 2023 Yoga could reduce risk of cancer relapse, say scientists. Gentle sessions may protect recovering patients by reducing inflammation.