The glyconutrient mannose is named after the word 'manna', that is mentioned in the Bible as the food God provided to the Israelites during their flight from Israel after crossing the Red Sea. It occurs naturally in a number of shrubs.
Its main natural dietary source is cranberries, and is one reason for the popularity of cranberry juice as a dietary supplement. However, the acidity of the cranberry juice can detract from the effectiveness of the sugar as a bactericide since many bacteria love acidic conditions. A case in point is the use of D-mannose to fight e-coli urinary infections.
Cranberry juice has been found to be largely ineffective due to the acidity of the juice that can cause the bacterium to multiply. The mannose content does not, in many cases, appear to be effective in eradicating the bacteria. D-mannose supplement, on the other hand, sticks to the wall of your bladder like glue, and attracts the bacteria. That is then stuck to the D-mannose and when the D-mannose in passed in your urine, the e-coli bacteria go with it. Many sufferers of urinary infections and cystitis have found it to be a very effective treatment. Significantly more effective that proprietary or prescription drugs and certainly better than cranberry juice.
That apart, mannose is one of the eight essential glyconutrients without which the human immune system would not be able to function. They are sugars known as monosaccharides, as opposed to the disaccharides such as sucrose, or common sugar, that is formed from glucose and fructose. Glucose is another such essential sugar, though fructose is not, causing more harm than good. Each of these sugars is essential to the mammalian biochemistry that was evolved over millions of years of a vegetarian diet. Human biochemistry diverged to include an omnivorous diet that depended a great deal not only on animal flesh, but on roots, canes, corn husks and other cereal seeds in their original form. This is why whole unprocessed foods are important in the diet.
Now, however, the human diet has changed, with intensive agricultural techniques and the refinement of foods to eliminate fibers and husks combining with processing techniques to render much of our food deficient in many nutrients that were in abundance in years past. Our biochemistry took millions of years to develop, and is not going to change in a few thousand. Among those nutrients that have become relatively scarcer in our diet are the essential monosaccharides that, until recently, were not considered important.
In fact, just over ten years it was thought that all sugars were burned in the body to produce energy that, if not immediately used, was stored as glycogen as a short-term energy source or fats as a longer term source of energy. In effect, they were regarded as irrelevant to the diet and even by many medical practitioners as harmful. It is now known that these eight glyconutrients as they are called play a much more fundamental role in human biochemistry and in ensuring our survival than was previously understood.
Incidentally, you will generally see the word mannose related to D-mannose. The 'D' stands for 'dextro' which comes from the Latin root for 'right'. Sinister and dexter are left and right in Latin, and the term dextrous was applied originally to one who could manipulate well with the right hand and fingers. Through time it became a definition for manipulation ability, or use of the fingers and hands, in general. However, in D-mannose it refers to the stereochemistry of the molecule, or the way that it is bent to the right. That is the common form, and will be referred to here as simply 'mannose'.
Mannose is one of these eight sugars that are essential for the proper functioning of the mammalian immune system, and that includes humans. A deficiency in any one of them will lead to a deficiency in the effectiveness of the immune system to fight disease. Not only disease, but failure of the immune system will lead to conditions such as allergies, possibly psoriasis, various forms of arthritis, and infections of many parts of the body, particularly of the respiratory tract that is one of the main causes of death in AIDS victims, another immune system disease.
The science and biochemistry of allergies is also not fully understood, but the immune system is now believed to play a significant part. Knowledge of any dietary element pertaining to this as yet mysterious part of the way the human body fights infection must be taken seriously, and dietary deficiencies made up by the use of supplements.
There are those that believe supplements to be not only unnecessary, but also damaging to health. However, much of this is born from ignorance and superstition, and modern biochemical knowledge must be used to ensure that all of us are supplied with the chemicals necessary for our well being. All food we eat, and nutrients we consume, are chemicals. That appears to be a bad word to some, but it is fact and we have to ensure that our chemical intake is sufficient to meet the needs of the biochemistry of our bodies. Without that the chemical reactions that permit life would not be possible.
Those that suffer from urinary infections have generally found that regular doses of mannose during the day are more effective than one or two larger doses. What this indicates is that the sugar is rapidly metabolized by the liver and excreted from the body, and so needs frequent replenishment. Since the natural sources of mannose are so small in this modern age, it is little wonder, then, that deficiency can be relatively common and we are no longer able to shrug off illness as quickly as our forefathers were able to.
In order to understand the effect of modern day nutrition, keep in mind what has already been said. Mannose is not only able to control e-coli infections in the bladder, but is also a critical component in the biochemistry necessary to keep our immune system healthy. It is the immune system that controls disease, creates and releases antibodies to kill off invading cells, controls the disposition of white blood cells that envelope and devour foreigners and determines how quickly we recover from minor wounds or serious injuries.
In saying that, laboratory studies indicate that excessive amounts of mannose could lead to some birth defects, though this is only thought to be relevant for mannose supplements. Although these supplements are very effective for most people therefore, pregnant women should seek medical advice prior to using mannose supplements.
Keep in mind the benefits of mannose and those defects only occur with large excess intakes. Under medical supervision, mannose supplements should not present a hazard to anyone. This must not be considered a deterrent to others to whom that does not apply, since the glyconutrient mannose is too important a substance in the chemistry of life for us to ignore.
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