Harmful psychological treatments are damaging and cause worse outcomes than would have occurred without treatment.

Evidence

Doing no harm in mindfulness-based programs: Conceptual issues and … (NIH)

corroborated: 2 independent passages support this claim
XREF: connects to: Mindlessness leads to panic and detrimental behavior. — Dan Harris, 10 percent Happier, 40; Meditation and mindfulness, widely perceived as stress-reduction techniques, can also have adverse effects. — Meditation And Mindfulness May Lead To Anxiety, Other Adverse Effects In …

A new harm monitoring study investigates the adverse effects of mindfulness-based practices. (similarity 0.86)
The most common adverse effects are anxiety and depression, followed by psychotic or delusional symptoms and dissociation. (similarity 0.83)
At least 25% of regular meditators have experienced adverse effects from mindfulness. (similarity 0.83)
Meditation practice in MBPs is associated with transient distress and negative impacts at similar rates to other psychological treatments. (similarity 0.81)
Meditation and mindfulness, widely perceived as stress-reduction techniques, can also have adverse effects. (similarity 0.81)
Studies have described adverse events such as anxiety, pain, and psychosis associated with mindfulness meditation. (similarity 0.81)
58% of 96 participants reported at least one meditation-related adverse effect, ranging from perpetual hypersensitivity to nightmares. (similarity 0.80)
Recent studies reveal that 25–87% of those who engage in meditation report adverse effects, with 3–37% experiencing functional impairment. (similarity 0.80)