A bowel movement to expel stool is the end of the line for your GI (gastrointestinal) tract. If you don't have sufficient bowel movements, that stool remains and the toxins from bacteria trapped in feces gets reabsorbed into the blood while it's packed in the colon or large intestine.
There are varying solutions and techniques for constipation and medical practitioners, both natural and mainstream, differ wildly in their approach at treating it. There are also many remedies that they agree upon.
Remedying constipation(1) Everyone seems to agree that a habit of holding it is a precursor to constipation. Whether this habit arrives from being restrained from using public bathrooms by oneself or others, this becomes a habit that dampens one's awareness of when it's time to go. Then what needs to come out dries out and hardens and the trouble begins.
(2) While eating, you may want to assist your pancreas by adding enzyme supplements with your meal. Enzymes are part of uncooked plant foods. Cooking harms these catalysts for digestion, so unless there's a lot of raw plant foods or juicing going on, supplementing enzymes may be necessary.
(3) A little water with unfiltered, non-pasteurized apple cider vinegar or a betaine HCL (hydrochloric) just before each meal is often recommended to boost stomach acids that begin the first major step of digestion, especially for older folks.
(4) The glass of warm lemon or lime water without any sweetener upon rising has been embraced by many of all ages to stimulate the liver and gall bladder's bile production, which is a fluid that combines with food enzymes and enzymes from the pancreas.
(5) Triphala is an excellent Ayurvedic herbal tonic for the lower GI tract and colon. Taking this daily before retiring or in the morning with that warm lemon/lime water has helped many with constipation issues.
It's not a quick solution, but over time your constipation concerns will begin resolving (http://www.naturalnews.com/027298_health_anti-aging_herbs.html).
(6) Low-fat diets offer more health problems than solutions on several accounts. When it comes to resolving constipation, it's better to consume a good amount of healthy fats, both animal and plant sourced.
Healthy fats are from organic sources and are unadulterated, not hydrogenated or otherwise processed (http://www.naturalnews.com/035069_low_fat_diet_myths_weight_loss.html).
(7) There is considerable agreement for maintaining a high probiotic content in the intestinal flora, for several reasons including the promotion of bowel movement regularity.
Along the way to restoring permanent healthy bowel movements, there are some quick temporary remedies for resolving acute issues. Consuming prune juice or prunes works for many, as does a couple of ounces of Castor oil in equal amounts of orange juice, or a tablespoon or two of castor oil before retiring.
A small footstool that raises your feet and legs while on the toilet emulates squatting on the ground and is helpful for eliminating more easily. Some use a small anal douche or enema bulb during toilet time to get things rolling. (118 Home remedy ... source below)
There are also some areas of dispute among the experts. Perhaps the most contrary and intriguing are offered by Konstantin Monastyrsky, an outspoken high level computer geek who graduated from Lviv National Medical University in Ukraine.
He doesn't currently practice medicine. Instead, he researched his own chronic digestive ills to cure himself and wrote about it. Sources providing more information are listed below.
Sources for this article include:118 Home Remedy Submissions (very interesting anecdotal solutions) http://www.constipationgoneforever.com/miracle_cure.htm
Konstantin Monastyrsky http://www.gutsense.org/gutsense/constipation.html
Konstantin Monastyrsky http://www.gutsense.org/gutsense/flora.html