Overview

• The umbrella review, published in Nature Human Behaviour, was led by teams at Paris Nanterre University, Paris Cité University and the University of Southampton.
• Researchers assessed 248 meta-analyses covering about 200 clinical trials and more than 10,000 participants across 19 complementary, alternative and integrative medicine categories.
• Interventions examined included probiotics, vitamin D, acupuncture, animal-assisted approaches, music therapy, special diets and sensory-based techniques.
• Reported benefits largely stemmed from low-quality studies, leading the authors to judge the effects as unreliable.
• Safety was seldom evaluated, with fewer than half of interventions having any assessment of acceptability, tolerability or adverse events, prompting calls for shared decision-making grounded in rigorous randomized evidence.