It could be normal for people with IBS (Irritable Bowel Syndrome). But one should be aware of alarming features / symptoms which excludes IBS like bleeding in the stools, pain in the stomach, weight loss and loss of appetite. If any or all the symptoms are there needs immediate attention to Rule out GI cancer or Inflammatory Bowel Disease (IBD). In this case may require some blood tests , stool rest and sometimes Colonoscopy