Table 2.

Studies reporting percentages of meditating samples (none from MBIs) describing negative or unwanted effects of meditation.

1st author, year	Sample	Percent reporting and types of negative effects	Comments
Otis, 1984	574 TM practitioners	4.5% - 13.5% reported anxiety, depression, confusion, or other symptoms	More experienced meditators reported more negative effects and more problems prior to taking up meditation
Shapiro, 1992	27 long-term Vipassana meditators	63% reported negative emotion, confusion, alienation, or other symptoms 7% reported severe effects (disorientation, depression) that led them to stop meditating	Many described unpleasant experiences as temporary and as learning opportunities Over 80% reported positive outcomes (joy, confidence, acceptance, compassion, problem solving, resilience) Psychiatric history not addressed
Cebolla, 2017	342 practitioners of many types of meditation	25.4% reported unwanted events (anxiety, pain, mood symptoms, other) 1% stopped meditating 5.7% sought professional help	Many described unwanted events as transitory Positive effects not addressed Psychiatric history not reported Extensive missing data
Lomas, 2015	30 male Buddhist meditators	100% described meditation as challenging (difficult, unpleasant thoughts and emotions) 25% of the interview data involved problems with meditation 20% reported threats to sense of reality 7% hospitalized (1 suicidal)	100% described meditation as valuable and conducive to wellbeing Many described difficulties (even severe ones) as important to their development