In this double-blind placebo-controlled randomised intervention we investigated the potential benefits of a prebiotic supplement on children’s well-being in a home setting. The primary aim was to determine if this supplement could effectively reduce anxiety, improve mood, and enhance cognitive function, similar to findings in young adults.

Fifty-three healthy children, aged 6 to 14, participated in an 8-week trial. The trial consisted of three testing time points; day zero marked the baseline measurement (T1) followed by a 28-day supplement intervention period during which they consumed 5.5 grams of galactooligosaccharides (GOS) daily under parental guidance. Endline measures (T2) were conducted on the last day of supplement consumption, with a final follow-up testing session (T3) on day 56. Primary outcomes were trait anxiety using a questionnaire and emotional behavior in a dot-probe task on responses to positive and negative images. Secondary outcomes encompassed depression levels, cognitive function tests, and dietary intake recorded in a 4-day food diary. Additionally, we explored whether parents’ emotional behavior had an impact on children’s responses.

While our statistical analysis did not reveal significant effects of GOS, there were noteworthy trends. Trait anxiety levels decreased over time in both groups, with a more pronounced decrease in the GOS group. The GOS group exhibited reduced negative emotional responses compared to the placebo group, and post-trial depression levels decreased in the GOS group over time. Although parental emotional responses correlated with various emotional outcomes in children, they did not influence the intervention effects. In conclusion, these findings suggest positive trends in line with our hypotheses however further investigation with greater statistical power would be beneficial.

The authors have declared no competing interest.

NCT06258135

This study was supported by FrieslandCampina, NL.

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The Ethics committee of The University of Surrey gave ethical approval for this work

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All data produced are available online at https://osf.io/nzkqw/?view_only=0f6734447fc34410908c3a20c64ba205