Answer :Robert M. Russell, MD, professor emeritus at Tufts Friedman School, answers: From a nutrition point of view it is not so much an issue of cleaning out but rather to achieve regular bowel movements. Taking psyllium (such as Metamucil and other brands) provides a good soluble fiber basis for regularity. Usually people who have problems with constipation take psyllium in the evening (one tablespoon) so that it is working by the morning. Some people need more, however, and take one tablespoon in the morning and also in the evening. The doses need to be individualized over time. It is important not to take too much at one time, however, as it will result in bloating, abdominal cramping and gas. It does not matter whether psyllium is taken with a meal or not.
If a person is not constipated, but likes the idea of cleaning out, I would only recommend taking psyllium no more than three times a week. But if one is not constipated, but desires regularity, a much better way to go is via a high-fiber diet. (For more on the health benefits of fiber, see page one in this issue.)