An examination of pertinent and under researched issues related to the growing use of mindfulness meditation (MM) and other contemplative practices in health care starts with discussions of the common understanding of mindfulness developed by John Kabat-Zinn’s (1994) who famously defined it as – “paying attention in a particular way, on purpose, in the present moment, non-judgmentally” (p.4).  Changing understandings of mindfulness, now impacting how it is taught and practiced, start with the differentiation of MM and Mindfulness Based Interventions (MBI).  MM practices are generally grouped into two primary types: focused attention and open monitoring (Vago & Silbersweig, 2012). MBIs, although often incorporating MM practices, generally do so within a larger collection of therapeutic techniques.  The most common MBIs are Mindfulness Based Stress Reduction (MBSR) (Kabat-Zinn, 1990), Mindfulness Based Cognitive Therapy (MBCT) (Segal, Williams, & Teasdale, 2002), Dialectical Behavioral Therapy (DBT) (Linehan, 1993), and Acceptance and Commitment Therapy (ACT) (Hayes, Strosahl, & Wilson, 1999).  This under researched issue introduces a number that are currently arising, which challenge the rapid adoption of contemplative practices such as MM.
 
In particular, while there are significant benefits to practicing mindfulness meditation and other contemplative practices interest is now turning to the potential harms associated with these practices.  Hanley et al. (2016) introduce their research into what they term the ‘other side of mindfulness’ by highlighting the attrition rates in MM and MBI courses.  They suggest that this aspect of these interventions is frequently ignored in the literature, but they have found, for example, that participants with a history of suicidal depression, depressive rumination, and younger participants who inconsistently take antidepressants were less likely to finish MBCT programs.  From this and other findings they construe that participant completion rates in both MBSR and MBCT are consistently aligned with participant motivation.  This confirms the often unspoken but compulsory aspect of engaging these programs, which is that they require significant effort, and while not a serious harm, failure to complete may exacerbate the depression experienced by those who drop out of these programs.
 
According to Hanley et al., (2016) it is only one of a wide range of adverse effects that can potentially arise from mindfulness and other contemplative practices.  While little theoretical attention has been paid to this aspect of meditation Hanley and his colleagues found a number of theorists working in this area.  Interestingly, this began in the 1970’s with seminal work done by theorists such as Roger Walsh and Lorin Roche and their 1979 “Precipitation of acute psychotic episodes by intensive meditation in individuals with a history of schizophrenia”.  More recently, as the use of meditation interventions has increased in a range of settings, theorists have returned to the issue of harms result from meditation.  Deane Shapiro (1992) found in his work with 27 experienced meditators on a 10 day silent Vipassana meditation retreat that despite an 80% positive response to the retreat, a significant proportion of retreatants reported negative effects.  These effects were divided into three major domains: Intrapersonal – increased negativity, disorientation, addiction to meditation, boredom and pain; Interpersonal – family conflicts as the retreatants became more judgmental; Societal effects – increased alienation, discomfort with the ‘real world’ (Shapiro in Hanley et al., 2016, p. 108).  It is important to note that these adverse effects appeared to transform over time and six months after the retreats participants reported that many of the issues were resolved.  Castillo (1990) describes similar adverse effects in his case-study, including depersonalization and associated anxiety and panic.  Relevant here is that depersonalization can be a function of the “nature of the ideational construction of the experience in the mind of the individual” (Castillo, 1990, p. 167), thus context and participant expectation is a determinate of the psychological distress associated with MM.  A form of meditation-induced psychosis is reported by Kuijpers et al. (2007) who provide the case study of a young man suffering acute but transient psychotic symptoms after a silent meditation retreat.  However, it is important to note that the young man had a history of mental illness and there were stressors including sudden weight loss resulting from recent marathon training. 
 
Kuijpers et al’s (2007) article provides an overview of 10 similar case studys of meditation-induced psychosis with more than half of those cases being with individuals who had psychiatric histories.  Fasting and sleep deprivation were implicated in a number of these situations and all but one of the individuals recovered in a time period of between a few days to 5 months after the incident.  Reporting on the phenomenon of meditation-induced psychosis Manocha (2000) advises that “meditation is contraindicated in those [individuals] suffering from psychosis and should only be applied with great caution in those with severe psychological problems” (pp. 1137-1138).  Kuijpers et al., (2007) arrive at a similar conclusion as they also highlight issues related to sleep deprivation, fasting and physical exhaustion.  Arias et al., (2006) caution that it is difficult to interpret the relationship between meditation and psychosis given the frequency of accompanying sleep and food deprivation in many of the reports. Accompanying, research on psychosis and meditation is a growing literature on the benefits of using mindfulness-based therapies in the treatment of psychosis.  Shonin et al. (2014) acknowledge that meditation may induce psychotic episodes though counter this by outlined that most of the evidence of this stems from case studies with low participant numbers who have engaged in intensive meditation retreats.  Shonin et al (2013) caution against intensive retreats where participants can meditate for up to 18 hours at a time often while fasting or with reduced food intake, as the extreme stress associated practice can in rare cases result in psychotic episodes.  Shonin et al. (2014) also differentiate between a wide range of contemplative practices such as Transcendental Meditation (TM) and Qigong and what they term ‘analytical meditative methods’ associated with Vipassana meditation and MM, suggesting that MM is a more ‘passive’ method particularly suited for those with mental ill health.  According to Shonin and his colleagues (2014) MM provides an attentional strategy (nonjudgmental open awareness anchored by breath-observance) that has been shown to “increase perceptual distance from cognitive and affective processes, which can be beneficial for those suffering from psychosis” (p. 126).  They conclude that MM used in clinical settings appears to be beneficial in the treatment of psychosis.
 
In addition to particular forms of contemplative practices playing a dual role in psychosis, there are specific adverse effects linked to certain practices.  In his research on the Chinese movement meditation practice of Qigong, Ng (1990) claims that it has been found to produce three types of ‘disturbances’: sensory, motor, and psychic.  Sensory disorders range from difficulty breathing, and nervousness to disturbed sleep and numbness or aching; motor disturbances that have been reported are: twitching, tremors or involuntary movements of the head and torso, which confirms Lustyk et al.’s (2009) proposition that meditation can increase epileptogenesis.  Psychic disturbances include alterations in consciousness such as confusion and disorientation, ‘spirit possession’ or feelings of bodily possession, distracting thoughts and delusions (Ng 1999).  In addition to these serious outcomes of contemplative practice there are ‘low level’ negative results that Lomas and his colleagues (2015) discovered in their research with 30 male contemplative practitioners in London, England.  They include the difficulty of acquiring particular skills needed to meditate, the struggle of integrating meditation into busy lives, the boredom of practice, and problems with tiredness or ambivalence (p. 10).  Lomas et al., (2015) also highlight gender specific problems with meditation, where they identified what they believe to be a problem with meditation, specific to men, related to their proposed restricted emotionality.  In their discussion of these issues Lomas etc al. (2015) acknowledge the more serious problems that can arise from meditation, which they found in their research with a quarter of their participants reporting substantial difficulties with meditation.
 
Each of the above mentioned studies introduces relevant points, apart from those already mentioned, which are important to understand when engaging the issue of harms associated with meditation. Starting with the need to acknowledge that there are vulnerable communities (Kuijpers, et al., 2006), the understanding that different practices can produce different outcomes (positive and negative), there are relevant cultural and gender issues (Ng 1990, Lomas, 2015) and the necessity for empathetic and qualified instructors (Hanley et al., 2016).  To conclude, Lustyk et al. (2009) systematize potential adverse effects of meditation by dividing them into three main categories: mental, physical and spiritual, while emphasizing that adverse mental effects are the most common.  These are: psychosis including schizophrenia, dissociative states, and affective and anxiety disorders such as bipolar disorders, manic states, and depression and anxiety.  Lustyk and his colleagues (2009) don’t detail negative physical and spiritual outcomes though the claim they are less common than the adverse mental effects of meditation, they also propose that the latter are rare.  It appears that serious adverse effects of meditation are uncommon while low level discomfort either resolves or is accepted because of the far greater benefits.  Lustyk et al. (2009) also ask why meditation can produce harm, suggesting there is little research in this area, while hypothesizing that it may simply be that meditation reveals existing mental, emotional and physical discomfort generally suppressed by daily activity.

References:
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Hanley, A., Abell, N., Osborn, D., Roehrig, A., & Canto, A. (2016). Mind the gaps: Are conclusions about mindfulness entirely conclusive? Journal of Counseling & Development, 94, 103-113.

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Segal, Z., Williams, J., & Teasdale, J. (2002). Mindfulness-based cognitive therapy for depression. New York, NY: Guilford Press.

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Vago, D., & Silbersweig, D. (2012). Self-awareness, self-regulation, and self-transcendence (S-Art): A framework for understanding the neurobiological mechanisms of mindfulness. Frontiers in Human Neuroscience, 6, 1-30. doi:doi:10.3389/fnhum.2012.00296

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