Milk fat globule membranes for psychological and physical health: qualitative results from the Employing Milk Phospholipids to Observe Well-being and Emotional Resilience (EMPOWER) randomised trial.

Background: Milk fat globule membranes (MFGM) present a nutritional intervention with the potential to improve psychological well-being and mitigate the negative effects of stress on health. The present study aimed to investigate participant's experience of different aspects of health during a trial of MFGM supplementation and determine the effect of MFGM on qualitative measures of psychological and physical well-being.

Methods: Seventy-three adults in New Zealand who were enrolled in a clinical trial to test MFGM supplementation for improvement of psychological well-being took part in a post-intervention interview. Participants and researchers remained blinded to intervention group allocation. Interviews were conducted over the video conferencing platform Zoom and transcribed. A mixed methods analytical approach included thematic analysis to identify emerging themes and χ regression models to examine frequency of improvements in different aspects of well-being between the MFGM and placebo groups.

Results: There were no significant demographic or psychological differences between interviewees and non-interviewed study participants. Four central themes emerged from the data for all participants: improved well-being, increased ability to cope with stress and improvements in mood, improvement in physical energy or activity, and improved sleep. The frequency of improved ability to cope with stress and improved sleep quality was significantly higher in participants who received MFGM supplementation compared to those receiving the placebo.

Conclusions: Qualitative data may capture aspects of improved sleep or psychological well-being not measured by rating scales. The results suggest that MFGM supplementation may improve the ability to cope with stress and improve sleep quality in healthy adults.