Over time, your gastrointestinal tract—the long, muscular tube made up of your esophagus, stomach, small intestine and large intestine—becomes less efficient. “The muscles become thinner, and the nerves that tell those muscles to contract or relax become less responsive,†says Maged Rizk, M.D., gastroenterologist at Cleveland Clinic. That can cause chronic problems like constipation and heartburn—no fun for anyone.
Luckily, small changes can help.
http://parade.com/450209/mtaylor-2/gut-check-how-to-help-out-your-gi-tract/