Constipation is a prevalent gastrointestinal condition. Beyond simple lifestyle measures (e.g. increasing fibre intake, hydration, levels of exercise), medical therapies are available for management. However, a sizeable number of sufferers are dissatisfied with drug treatments (either over-the-counter or prescribed), meaning there is an unmet need for alternative therapeutic strategies. Pre, pro- and synbiotics have emerged as one alternative treatment, and a growing body of evidence now supports their use in a proportion of individuals with mild constipation. However, we are currently unable to predict which individuals may benefit. A better understanding of an individuals' symptoms and underlying pathophysiology may allow for more targeted treatment. We are testing a multistrain live bacterial food product (probiotic) containing billions of live and active bacteria that has been shown to improve symptoms in the irritable bowel syndrome (IBS: which is 'constipation-predominant' in many). Notably, improvements ('completely resolved' or 'some positive difference') in bowel habit satisfaction, abdominal pain, bloating and urgency, as well as on quality of life have been shown after 4 or more weeks of this probiotc. This study aims to have 20 participants with self-reported constipation to assess improvements in constipation symptoms, quality of life and measures of gut function.