Great responses to a great question, indeed. What is left for me to answer here is that magnesium oxides don't act as laxatives but as cleansers. Their purpose is not to trigger peristalsis but through oxidation remove the obstructive waste matter that prevents bile from coming into contact with the intestinal wall. Along with the production of intestinal gas (about 10 liters per meal) bile is the key trigger for peristaltic action. Restricted bile secretion from the liver and gallbladder leads loss of peristalsis. This further increases toxicity from undigested food and causes excessive toxin-filled gases to damage or destroy the nerve endings required for triggering proper peristalsis. Constipation is a typical disorder of poor bile secretion. Herbal laxatives, such as senna and cascara can be habit-forming and through their irritating effects (high antibody content) injure the nerve endings and intestinal lining. Besides, the don't address the root causes of the problem. Whenever I recommend colosan, oxy-powder or oxyflush, I emphasize that digestive functions need to be improved through liver flushing and adjustment of diet and lifestyle. Otherwise, these good products are just bandaids. In any case, it is not a good idea to rely on any product for long periods of time. You would want to retrain the body to do its job, not take over the job.