A feasibility study of the effects of concurrent transcranial direct current stimulation (tDCS) on mindfulness training in adults living with overweight or obesity: the MINDED trial protocol

Pilot Feasibility Stud. 2026 Jan 6. doi: 10.1186/s40814-025-01748-9. Online ahead of print.

ABSTRACT

BACKGROUND: This study protocol describes the use of two brain-directed treatments, i.e. mindfulness training (MT) and transcranial direct current stimulation (tDCS), as interventions for obesity-related behaviours (e.g. food craving, over-eating). Individually, mindfulness and tDCS are promising interventions for addressing maladaptive eating behaviours. We hypothesise that clinical outcomes from MT and tDCS will be improved when the two interventions are combined.

METHODS: This protocol is described in accordance with SPIRIT guidelines for clinical trials. The study is a feasibility double-blind randomised sham-controlled (RCT) trial of MT concurrent with or without self-administered tDCS in adults with obesity/overweight (BMI ≥ 25 kg/m²) (the MINDED trial). Sixty-six adults will be randomly allocated to one of three groups: MT with active tDCS, MT with sham tDCS or waiting list control. Participants in both intervention arms will be asked to complete daily app-based MT for 8 weeks post-randomisation. They will also receive 10 sessions of active or sham tDCS over the first 3 weeks post-randomisation. On tDCS-days, MT will be delivered concurrently. Feasibility will be evaluated by recruitment, retention, and follow-up rates. Acceptability will be determined by monitoring side effects and by participant ratings. Clinical and cognitive outcomes (e.g. body fat percentage and working memory) will be assessed at baseline (T0), 3 weeks post-randomisation (T1) and 8 weeks post-randomisation (T2).

DISCUSSION: The study will establish the feasibility of conducting a large-scale RCT of (MT + real tDCS) in adults with BMI ≥ 25 kg/m² classified as overweight or obese. This will involve assessing recruitment, retention and follow-up rates together with measures of acceptability and credibility. It will provide preliminary evidence on the clinical efficacy of the concurrent administration of tDCS and MT for people with obesity/overweight and preliminary information on possible underlying mechanisms (e.g. change in neurocognitive outcomes).

TRIAL REGISTRATION: ClinicalTrials.gov Identifier (NCT number): NCT05865912. Registered on 19 May 2023.

PMID:41495839 | DOI:10.1186/s40814-025-01748-9