Most of us who have investigated treatments for constipation will have come across the prune. These dried fruits are regarded as generally beneficial for relieving constipation, largely due to the large amount of fiber. But what many don’t know about is that the juice from prunes is also an excellent type of treatment.
The prune is simply a dried plum known by the scientific name of Prunus domestica. Archaeological evidence suggests that man has been cultivating plums and drying them for hundreds if not thousands of years. The method of processing is quite simple: 18 hours of hot air dehydration, typically at 90 degrees Celsius. After dehydration, the material can be further processed into other products like prune juice.
The usual understanding for most people is that prunes are good natural laxatives because of their dietary fiber content. How then does prune juice, which has no fiber at all because of filtration, help those who suffer from constipation? The answer is that sorbitol, a polysaccharide sugar substitute, has some wondrous laxative properties.
The content of sorbitol in prune juice is amazingly high. The sugar is a complex polysaccharide, meaning that it’s an extended chain of sugar-like molecules. When ingested, it tends to absorb a lot of water and stays in gut. In fact, because it’s not absorbed in the same way as glucose, sorbitol is often used as a sweetener that is calorie free.
The pear is another food that is high in sorbitol. If you’ve chewed sugar free gum in the past, you might have noticed that a key ingredient is sorbitol. Unlike glucose, sorbitol isn’t processed and taken in as energy. Couple that with its slightly sweet taste means that it’s the perfect sugar substitute.
Why does sorbitol act like a natural laxative? There are two properties already mentioned which are responsible: first, it passes through the body without being absorbed, much as dietary fiber; second, it retains a large amount of water as it goes through the gut. Either water that is taken in at the same time is retained in the gastrointestinal tract, or water is drawn from the surrounding tissues into the gastrointestinal tract.
The extra water and fluids means that the food mass becomes soft, dense, and thus moves more quickly through the gastrointestinal pathway. There are a number of other laxative agents that behave this way, and they are known as either osmotic or bulk laxatives. Prune juice, fortunately, is one of those things that one may drink anyway for other health benefits. That it’s a useful laxative is an added bonus for those interested in this class of treatments.
