There are generally four types of laxatives
(1):
- Stimulant Laxatives - as the name implies, these stimulate peristalsis directly. Example: Correctol
- Bulk Laxatives - add bulk to the bolus of food as it moves through your intestines so the intestines have something more to push against during peristalsis. This also has the effect of speeding things along so less water is reabsorbed from the stool in the large intestine which makes the stool softer. Example: Metamucil
- Saline (Hyperosmolar) Laxatives - create an osmotic gradient in the intestines which is favorable to a higher retention of water in the stool, thus making them softer. Examples: Milk of Magnesia, Ascorbate
- Emollient Laxatives - makes the digestive tract slippery so that stool can slide through. May also help stool retain some fat. Examples: Colace, Mineral Oil
The warning you have heard regarding your bowel habituating to laxatives only applies to
stimulant laxatives.
Bulk laxatives are encouraged all the time. The media has been harping on how to add more fiber to your diet for decades (anyone remember the SNL
"Colon Blow" skit with Phil Hartman?).
Non-mineral saline laxatives are also generally very safe. Mineral-based ones need to be used cautiously by those with kidney disease but are safe for most people.
I don't see how bowel tolerance doses of Vitamin C can do anything other than benefit your digestive tract. Exceeding bowel tolerance only results in the remainder being left in the gut to act as a purely hyperosmolar agent so that more water is retained.
In
http://www.orthomed.com/titrate.htm Dr. Cathcart writes
(2):
I think it is only that excess amount of ascorbate not absorbed into the body which causes diarrhea; what does not reach the rectum, does not cause diarrhea.
It is interesting to know, when one speculates on the exact cause of this diarrhea, that while a hypertonic solution of sodium ascorbate is being administered intravenously, the amount of ascorbic acid tolerated orally actually increases.
I will say that I don't believe anyone should be giving themselves diarrhea everyday though because it can result in electrolyte loss and dehydration which could have some very negative consequences. The trick with bowel tolerance, as I believe David has written elsewhere, is learning to recognize the signs that it is approaching and backing off just before crossing that threshold.
Cathcart again:
The patient tries to TITRATE between that amount which begins to make him feel better and that amount which almost but not quite causes diarrhea.
(Emphasis added)
Can cessation of Vitamin C megadosing lead to digestive trouble? Sure, digestive trouble, heart trouble, cancer trouble and a whole lot more by leaving you in the same hypoascorbemic state you were in before you started.
References:
1.
http://www.fpnotebook.com/GI176.htm
2.
http://www.orthomed.com/titrate.htm