Perilla Extract improves gastrointestinal discomfort in a randomized placebo controlled double blind human pilot study

BACKGROUND Gastrointestinal (GI) discomfort, e.g. bloating or rumbling, is a common symptom in otherwise healthy adults. Approximately 20% of the population, particularly women suffer from gastrointestinal discomfort and this affects quality of life. Recent studies discovered a link between the body and mind, called the gut-brain axis. Psychosocial factors, such as e.g. daily stress may cause altered gut physiology leading to ileum contractions and consequently gastrointestinal symptoms. In vitro and ex vivo studies clearly showed that a Perilla frutescens extract combines prokinetic, antispasmodic and anti-inflammatory effects. The aim of the intervention was to investigate the effects of the proprietary Perilla extract on GI discomfort in healthy subjects with gastrointestinal discomfort and reduced bowel movements in comparison to a placebo product. METHODS The pilot study was performed according to a double-blind, randomized, placebo-controlled parallel design. Fifty healthy subjects with gastrointestinal discomfort and reduced bowel movements, 30-70 years, documented their GI symptoms, stool frequency and consistency daily during a 2-week run-in phase and a 4-week intervention phase with Perilla frutescens extract or placebo. GI symptoms were assessed on a 5-point scale daily and average scores over 14 days intervals were calculated. RESULTS All GI symptoms were significantly improved over time by Perilla frutescens extract during the intervention phase (bloating: -0.44±0.56, p=0.0003; passage of gas: -0.30±0.66, p=0.0264; GI rumbling: -0.55±0.87, p=0.0014; feeling of fullness: -0.36±0.72, p=0.0152; abdominal discomfort: -0.54±0.75, p=0.004), whereas in the placebo group only abdominal discomfort was significantly improved (-0.31±0.55, p=0.0345). In the subgroup of women results were strengthened and a subscore out of bloating and abdominal discomfort was significantly improved against placebo (95%CI 0.003 to 0.77; p=0.048). CONCLUSION The demonstrated effects of Perilla frutescens extract to improve GI complaints offer very promising results, taking into consideration the challenging set up of a nutritional human study with healthy subjects and in the area of digestive health, which is known for high placebo effects. TRIAL REGISTRATION NUMBER NCT01931930 at ClinicalTrials.gov, Registration date 23rd August 2013.