Can Hypnosis Boost Your Immune System?

What the research says about hypnotherapy, stress, T-cells and immune health

Can hypnosis really boost your immune system? The answer is more interesting than you might expect.

Research into hypnosis, guided imagery and relaxation has found changes in immune function, including changes in T-cells and natural killer cells. One small study found that medical students using immune-related imagery during hypnosis reported fewer viral illnesses during a stressful examination period. Another study involving people with recurrent genital herpes found that six weeks of self-hypnosis was associated with almost half as many recurrences.

This is not to say that hypnosis is not a magic immune booster. It cannot make you immune to infection, and it is certainly not a substitute for medical treatment, good nutrition, exercise or sleep.

Research is encouraging, but more research is needed. (There are some serious problems with researching hypnosis — this will be my next blog!)

So what is going on?

Your mind and immune system are connected

The immune system does not operate in isolation from the rest of the body. Your brain, nervous system, endocrine system and immune system are in constant communication. Stress is one of the important links between them.

Chronic stress can affect immune function, including inflammatory processes and the body's response to challenges such as infection, vaccination and tissue injury. A 2019 systematic review and meta-analysis looked at 75 studies of stress-reducing psychological intervention, including relaxation, stress management, mindfulness, cognitive behavioural approaches and hypnosis. Twelve of the 82 interventions studied were hypnosis-based. The data demonstrated an overall improvement in immune responses, although the overall effect was modest and the studies were quite varied.

The evidence suggests that reducing psychological stress can influence immune function. The question is: can hypnosis help with that?

Hypnosis can help with stress

Hypnosis is a deeply relaxed but focused state. For many people, it is an effective way of changing the way they respond to stress, anxiety and difficult thoughts.

There is good evidence for hypnosis in reducing anxiety. A 2019 meta-analysis of 17 trials found that hypnosis produced a significant reduction in anxiety compared with control conditions, with even stronger effects when hypnosis was combined with other psychological approaches.

In one review of nine RCTs, six out of nine studies reported significant positive effects of hypnosis for stress reduction in the main outcome parameter compared to control groups, although the reviewers said that due to to exploratory designs and high risk of bias the effectiveness was not clear enough and more research is needed.

There are individual promising studies. One trial found that compared to the control group, the hypnosis group showed reduced perceived stress after 5 and 12  weeks.

Hypnosis and T-cells

T-cells are an important part of the immune system. Among other functions, they help identify and deal with infected or abnormal cells.

In one of Gruzelier's studies, medical students were given self-hypnosis training before their exams. The researchers measured several types of immune cells, including CD4 and CD8 T-cells, as well as natural killer cells and cortisol. The students who did not receive hypnosis showed a decline in CD8 cytotoxic T-cells during the examination period. The hypnosis groups showed a buffering of this decline.

These findings demonstrate that hypnosis can strengthen the immune system and improve well-being.

And, interestingly, the effect was associated with hypnotic susceptibility: students who were more responsive to hypnosis tended to show a stronger immune response.

The power of imagery and visualisation

Perhaps the most fascinating part is that Gruzelier and his colleagues compared different forms of self-hypnosis. Some students were given imagery specifically related to improving immune function while others were given relaxation imagery.

The immune-related imagery produced better results on several immune measures and was associated with fewer reported viral illnesses, including colds and influenza, during the examination period. The targeted imagery was also more successful than relaxation imagery in buffering declines in lymphocytes.

This suggests that hypnosis doesn’t work simply by making somebody relaxed, the content of the imagery may matter too.

That makes intuitive sense. The brain is remarkably responsive to imagined experience. We can become physically tense simply by imagining something frightening, and we can experience genuine emotional and physiological changes when we vividly imagine something pleasant or threatening.

The immune system is part of that same interconnected network.

Hypnotisability influences the effect

Another intriguing finding is that people differ in their responsiveness to hypnosis. Now, this is something I see all the time in practice. I generally think that hypnosis can benefit everyone, but some people definitely benefit more quickly and more dramatically.

Hypnotisability is not simply a question of whether someone 'believes in hypnosis’, it is a measurable individual difference in responsiveness to hypnotic suggestions. (There are a few scales of hypnotisability which are commonly used by researchers such as the SHCH, The Harvard Group Scale and Hypnotic Induction Eye Roll. These are all useful but they all have their limitations — in real life, a hypnotist can gauge from the first sessions how hypnotisable someone is.)

In the medical student research, hypnotic susceptibility was associated with the buffering of CD8 T-cell decline. The Gruzelier review also reports associations between hypnotic susceptibility or absorption and changes in immune function.

However, this does not mean that only highly hypnotisable people can benefit.

In the later herpes study, hypnotisability was associated with some immune and mood changes, but the researchers also found that clinical improvement was predicted by another personality characteristic, which they called 'cognitive activation', which is an individual's capacity for intense focused attention, mental absorption, and left-hemisphere brain activity. The authors concluded that health improvements were not restricted to people with high hypnotic susceptibility. (I would add that I find that people who are easily absorbed in activities are often more hypnotisable, i.e. in my opinion conitive activation and hypnotisability are linked.)

There is no simple 'good at hypnosis = better immune system' equation. Human beings are more complicated than that and hypnosis is still not understood well enough.

Hypnosis helped herpes

This is probably the most striking hypnosis-specific study in the review. People with chronic, severe recurrent genital herpes (HSV-2) underwent six weeks of self-hypnosis training.

The number of herpes recurrences during the six-week period was almost halved. The researchers reported that 65% of participants benefited. People who responded clinically also showed increases in natural killer cell activity against herpes-infected cells and changes in other immune measures. Anxiety and depression also improved.

The details are fascinating. In the whole group, the number of episodes during six weeks fell from an average of 2.1 before treatment to 1.3 afterwards. Among the clinical responders, the reduction was considerably larger.

I must note that it was a small study and did not have the kind of large, randomised controlled design we would want before concluding that hypnotherapy is a bona fide treatment for herpes. The authors themselves described the findings as preliminary. But it is very promising and similar results have been reported by clinicians at the British Society of Clinical & Academic Hypnosis.

So, can hypnosis boost your immune system?

The answer is that yes, possibly, hypnosis can boost your immune system — although 'boost' is probably not the best scientific word. There is evidence that hypnosis can influence stress, mood and physiological processes. There is also evidence that psychological interventions can influence immune function. And there are some intriguing hypnosis-specific studies showing changes in T-cells, natural killer cells, immune-related imagery and even reported illness.

I also think it is fair to say there is still so much we don't know about all the ways in which hypnosis can positively affect your health, wellbeing and immune system. I am eager for more research into how hypnosis can do this using specific techniques such as visualisation. My feeling from practice is that it is a powerful tool, although this will depend on the person, as some people 'see' things more easily than others, while some people are more kinaesthetic or audio.

At the most basic level, when you are chronically stressed, anxious or overwhelmed, your body is dealing with more than one challenge at once. Learning to regulate your response to stress may therefore be useful for your health in ways that go beyond simply feeling calmer. This one of the reasons I teach self-hypnosis to people when it is appropriate. The aim is not to become dependent on the therapist. It is to learn a skill that you can use yourself, whenever you need it.

Your immune system is not a machine with an on/off switch, but your mind and body are communicating all the time. It makes sense to pay attention to the conversation and help it to be a positive one!

If you would like to explore hypnotherapy for stress, anxiety or general wellbeing, please get in touch.

References

Gruzelier, J.H. (2002). A review of the impact of hypnosis, relaxation, guided imagery and individual differences on aspects of immunity and health. Stress, 5(2), 147–163.

Gruzelier, J.H., Levy, J., Williams, J. & Henderson, D. (2001). Self-hypnosis and exam stress: Comparing immune and relaxation-related imagery for influences on immunity, health and mood. Contemporary Hypnosis, 18(2), 73–88.

Gruzelier, J.H., Champion, A., Fox, P. et al. (2002). Individual differences in personality, immunology and mood in patients undergoing self-hypnosis training for the successful treatment of a chronic viral illness, HSV-2. Contemporary Hypnosis, 19(4), 149–166.

Schakel, L., Veldhuijzen, D.S., Crompvoets, P.I., Bosch, J.A., Cohen, S., & others. (2019). Effectiveness of stress-reducing interventions on the response to challenges to the immune system: A meta-analytic review. Psychotherapy and Psychosomatics, 88(5), 274–286.

Shields, G.S., Spahr, C.M. & Slavich, G.M. (2020). Psychosocial interventions and immune system function: A systematic review and meta-analysis of randomized clinical trials. JAMA Psychiatry, 77(10), 1031–1043.

Fisch, S., Brinkhaus, B. & Teut, M. (2017). Hypnosis in patients with perceived stress: A systematic review. BMC Complementary and Alternative Medicine, 17, 323.

Fisch, S., Trivaković-Thiel, S., Roll, S. et al. Group hypnosis for stress reduction and improved stress coping: a multicenter randomized controlled trial. BMC Complement Med Ther 20, 344 (2020).