New evidence presented at the 3rd Long COVID International Conference 2025 suggests that taking Symprove, the liquid multi-strain live and active bacteria food supplement, may support cognitive function in adults living with Long COVID.
Researchers at Sheffield Hallam University conducted a 12-week, randomised, double-blind, placebo-controlled trial to investigate the effect of Symprove on cognitive impairment - one of the most persistent and debilitating symptoms of Long COVID. Cognitive symptoms often include reduced attention spans, working memory, and executive function, all of which can significantly affect quality of life and social participation.
The study recruited 39 adults diagnosed with Long COVID, who were randomly assigned to receive either Symprove or a placebo. Participants were assessed at baseline and at the end of the intervention for a range of outcomes, including cognitive function gastrointestinal symptoms, and fatigue severity. This analysis was part of a bigger study of 198 adults reviewing the effects of Symprove in Long COVID, and full analysis and publication are still pending. Larger trials are warranted to confirm efficacy and explore the durability of cognitive improvements.
Participants who received Symprove demonstrated significantly greater improvement in cognitive function from baseline to 12 weeks compared to the placebo group. These changes suggest improved executive function, memory consolidation, spatial planning, and problem solving. Additionally, participants taking Symprove saw a clinically meaningful difference in fatigue and significant results gastrointestinal symptoms such as reflux and indigestion compared to placebo.
Dr Caroline Dalton, Sheffield Hallam University and lead investigator, says “These findings are encouraging because they suggest that targeting the gut microbiome may be an effective approach to supporting people with Long COVID.”
This early research study adds to a growing body of investigations exploring the gut–brain axis in post-viral recovery, and these findings provide early clinical evidence that supporting the gut microbiome may help people living with Long COVID symptoms.
The abstract presented at the 3rd Long COVID International Conference 2025 can be viewed here.
About Symprove:
Symprove is the UK's No.1 live and active bacteria supplement*.
Founded in 1986, Symprove has spent decades investing in independent scientific research to help build a better understanding of the gut microbiome and the role it plays in overall health.
Unlike many supplements, Symprove's unique water-based formula is designed to deliver live and active bacteria to the gut, where they can have the greatest impact. It contains four strains of live and active bacteria, is suitable for everyday use and is free from dairy, gluten and artificial additives.
Today, Symprove is available on subscription from symprove.com and at leading UK retailers including Tesco, Boots, Sainsbury's, Waitrose, Superdrug, and Holland & Barrett.
For more information, visit www.symprove.com.
For samples or more information, please get in touch with press@symprove.com or call 01252 413 600.
* Source Euromonitor International Ltd; Consumer Health 2026ed., Symprove retail value sales, UK 2025 data
