The effect of pectin supplementation on geriatric individuals with frailty: a randomised placebo-controlled dietary intervention study.

Frailty is associated with impaired physical function, psychological decline, and alterations in the gut microbiome, yet nutritional strategies targeting these interconnected pathways remain limited. Low-methoxy (LM) pectin, a fermentable dietary fibre derived from plant cell walls, has demonstrated immunomodulatory and microbiome-modifying effects in preclinical studies, but evidence in older adults with frailty is scarce. We conducted a 4-week double-blind, randomised, placebo-controlled trial evaluating LM pectin supplementation in older adults with frailty. Thirty-one participants were enrolled, and 29 completed the intervention. Physical performance, psychological well-being, quality of life, inflammatory biomarkers, and gut microbiome composition were assessed at baseline and follow-up. Compared with placebo, low-methoxy pectin supplementation significantly improved lower limb function measured by the 30-second sit-to-stand test (2.07 ± 1.94 vs 0.71 ± 2.27 repetitions; p = 0.038), while no significant changes were observed in Timed Up and Go performance. Supplementation also reduced anxiety and depression scores and improved several Short Form-36 domains, including physical functioning, vitality, mental health, and social functioning. No significant differences were detected in circulating inflammatory biomarkers. Gut microbiome analysis demonstrated increased relative abundance of Coprococcus comes, an acetate-producing species linked to gut-brain signalling and psychological health. These findings provide preliminary evidence that LM pectin supplementation may improve physical and psychological outcomes and alter gut microbial composition in older adults with frailty. Larger, adequately powered trials are needed to determine whether these changes are reproducible and to investigate potential microbiome-related mechanisms. Trial registration number: NCT06955975 ( https://clinicaltrials.gov/study/NCT06955975 ; Clinical Trials.gov; 2025-06-22).