It is common for people who are suffering from irritable bowel syndrome (IBS) to also struggle with depression. Now, a new study suggests that taking a probiotic supplement may provide relief from both conditions. A research from McMaster University in Canada recruited 44 adults with IBS as well as mild to moderate anxiety or depression. They were followed for 10 weeks; 22 subjects took a daily dose of the probiotic Bifidobacterium longum, and the rest of the subject took a placebo. After six weeks, twice as many people who took the probiotic had decreased depression scores compared to those who took the placebo.