A ground-breaking clinical trial has demonstrated that an over-the-counter supplement can significantly reduce symptoms of irritable bowel syndrome with diarrhoea (IBS-D), a condition affecting up to 42% of all IBS cases. The AltruVita Healthy Gut formulation, combining curcumin, green tea polyphenols and vitamin D3, produced clinically meaningful improvements in symptom severity after just four weeks, according to findings presented at the British Gastroenterology Conference BSG LIVE ‘26 on June 24.
Study Design and Results
The trial, conducted by the Functional Gut Clinic, involved 78 adults diagnosed with moderate-to-severe IBS-D. It was a randomised, double-blind, placebo-controlled study. During the first four-week 'blind' phase, half of participants took the supplement daily and half took a placebo. Those on the supplement experienced clear, clinically significant improvements in symptoms, while the placebo group did not. In the subsequent four-week 'open' phase, all participants knowingly took AltruVita Healthy Gut, and all reported a reduction in symptoms.
Professor Martyn Caplin, lead author of the study, stated: 'While managing moderate-to-severe IBS-D remains a complex clinical challenge, this trial represents a meaningful step forward in validating natural interventions. Achieving a statistically significant and clinically relevant reduction in the IBS Symptom Severity Score demonstrates that the right natural compound can actively improve IBS symptoms and therefore enhance patient quality of life.'
Impact on Daily Life
Claire Smith, 37, a full-time mother of three from Richmond, London, shared her experience: 'I spent a lot of time worrying about my symptoms – being able to get on with life has made a huge difference. The bloating made me feel really uncomfortable, but it was the urgency that I found hardest. I'd often feel fine one minute and then suddenly feel like I needed a toilet straight away.' She added: 'After starting AltruVita Healthy Gut, I began noticing positive changes within a really short time. The bloating became less frequent, my digestion felt much calmer, and I wasn't experiencing the same urgency.'
According to a Censuswide survey last September, more than half of British adults (55%) suffer from persistent gut health issues, including IBS, with one in six (16%) regularly struggling with chronic diarrhoea. Experts estimate that IBS-D affects 25-42% of all IBS cases. The survey also found that nearly half (48%) of respondents would prefer a natural product over prescription medication.
Expert Commentary
Sam Treadway, Principal Clinical Scientist at The Functional Gut Clinic, commented: 'For too long, IBS-D patients have had to choose between highly restrictive diets, prescription medications that often carry unwanted side effects, or unproven natural supplements. The data from the AltruVita Healthy Gut trial provides robust findings that targeting the gut with the right combination of natural ingredients works significantly better than a placebo.'
Nutritionist Kate Cook, founder of The Nutrition Network, said: 'In my years as a nutritionist, I’ve seen first-hand how disruptive IBS can be to a person's daily life. Finding a solution that actually works, and that clients feel comfortable taking long-term, is incredibly challenging. So, it is heartening to see such a rigorously researched, gold-standard clinical trial in the natural supplement space.'
Mechanism and Availability
The AltruVita Healthy Gut formulation leverages the combined mechanisms of three components: curcumin, which facilitates fat digestion, reduces inflammation and supports overall digestive comfort; green tea polyphenols, which protect the stomach lining and have anti-inflammatory effects; and vitamin D3, which supports normal immune function. The supplement is available at £24.95 for 60 capsules via altruvita.com.
Katie Murray, specialist nutritionist at AltruVita, added: 'Our unique blend of highly absorbable curcumin, low-caffeine green tea, and vitamin D3 was shown to significantly contribute to digestive comfort and reduce the symptoms of IBS-D. We are giving IBS-D sufferers a scientifically backed, gentle and effective option that supports the health of the digestive tract.'
