What is xylitol?
Xylitol is a sweetener that occurs naturally. It can be found, for instance, in berries, fruit, vegetables and mushrooms. The Finnish name for it, "koivusokeri", or "birch sugar", derives from the fact that the best way to make xylitol industrially is from birch, by chopping up and rendering down the structural fibre of the wood, xylan.
Where does xylitol occur in nature?
Xylitol occur in small amounts in natural form, especially in fruit, berries, vegetables and mushrooms. For example raspberry, strawberry, yellow plum and endive contain xylitol. Xylitol also occurs in human tissues.
What is the difference between xylitol and other sweeteners?
Chemically speaking, xylitol is not actually a sugar, but a sugar alcohol. It differs from other sweeteners such as sorbitol, fructose and glucose because the xylitol molecule has five, instead of six, carbon atoms. Most bacterias in mouth are unable to make use of 5 carbon sugars. This is one reason why xylitol helps prevent caries.
Xylitol is much sweeter than sorbitol, for instance. Assessed in terms of calories, its sweetening power is the same as that of sucrose. It is also similar to sucrose in its technical and nutritive properties. Xylitol is an important supplement in the prevention of dental caries, and everyone interested in healthy teeth should be familiar with its properties and effects.
Where was xylitol discovered?
Xylitol was discovered almost simultaneously by German and French chemists way back in the late 19th century. In the Soviet Union it has been used for decades as a sweetener for diabetics, and in Germany in solutions for intravenous feeding. In China, xylitol has been used for various medical purposes.
The dental significance of xylitol was "discovered" in Finland in the early 70's, when scientists at Turku University showed it could prevent caries.
Xylitol-Jenkki, the first xylitol chewing gum in the world, was launched by the Finnish company Leaf in 1975.
How does an acid attack occur?
Modern science tells us that caries are the result of a combined effect of microorganisms and sugar. Certain bacteria, the worst being streptococcus mutans stick to the surface of the teeth. Every bite of food containing ordinary sugar, i.e. sucrose, gives the bacteria energy, allowing them to multiply and start producing acids by a metabolic process. The result is the infamous "acid attack". When the pH of this mass of bacteria, or plaque, falls below pH 5,5, calcium and phosphate salts start dissolving from the surface of the enamel. Cavities begin to form, though only very slowly at first.
After eating sugar it takes over half an hour before the pH of plaque is restored to the normal level of around 7. If sugar is eaten several times a day, salts are dissolved off the enamel more and more deeply and the enamel becomes porous.
Why is xylitol so tooth friendly?
When you take xylitol, the acid attack that would otherwise last for over half an hour, is stopped. Because the bacteria in the mouth causing caries are unable to ferment xylitol in their metabolism, their growth is reduced. The number of acid-producing lactobacilli and streptococci may fall as much as 90%. No acid is formed because the pH of saliva and plaque does not fall. After taking xylitol, the bacteria do not stick well on the surface of the teeth and the amount of plaque decreases.
Research has shown that the use of xylitol also helps correct existing damage to the enamel. Saliva in itself protects the mouth and teeth. Stimulated saliva in particular contains all the components needed to correct incipient caries. If sugar is only taken a couple of times a day, the saliva can do the job alone. But most people take sugar (or starch) so often that the mouth's own defensive mechanisms are not enough.
Saliva containing xylitol is more alkaline than saliva stimulated by other sugar products. After taking xylitol products, the concentration of basic amino acids and ammonia in saliva and plaque may rise, and plaque pH rises as well. When pH is above 7, calcium and phosphate salts in saliva start to precipitate into those parts of enamel where they are lacking. Thus, soft, calcium-deficient enamel sites begin to harden again.
Is xylitol safe?
Yes. JECFA, a joint expert committee of WHO and FAO, confirmed in 1983 the fact, already known by scientists, that xylitol is a safe sweetener for foods. The FDA confirmed this in 1986.
Does xylitol take care of a mouth dryness problem?
Yes. In terms of dental health, it is good to increase the salivary flow rate as often as possible, i.e. to secrete what is called stimulated saliva. The faster the saliva flow, the greater its buffer capacity, that is, its power of resisting the drops in saliva pH and thus in plaque pH.
In stimulating saliva secretion xylitol increases the amount of saliva in the mouth. At the same time it increases saliva's initiate chemical capacity for reducing the harmful effects of bacteria.
Sucrose also stimulates saliva secretion, but even this increased salivary flow rate cannot compensate for the effect of the acids simultaneously produced by the cariogenic bacteria. So plaque pH falls and cavities start forming.
Chewing also helps promote saliva secretion. That's why chewing gum is an almost perfect way of taking xylitol from the dentist's point of view.
How much xylitol should one eat per day?
The anticariogenic (anti-cavity causing) effect of xylitol stems partly from the affected bacteria population in the mouth and partly from the properties of saliva. Xylitol is a natural and convenient way of supplementing daily dental care. Research shows that a mere 5-10g/ day is enough. In practice, this means 3-8 pieces of chewing gum a day. The pieces should be chewed immediately after a meal or a snack. If you eat more snacks, you of course need more frequent help from xylitol.
Why is xylitol an important aid in caries prevention?
Xylitol is one of the most important alternatives to sugar. Xylitol is more than a mere substitute; it is a therapeutic sweetener. That is why xylitol chewing gum and other xylitol products play an important role as instruments of dental care, in a part of caries prevention.
Is it possible to replace daily teeth cleaning by xylitol?
No. You still need good oral hygiene. A healthy mouth and teeth are an important part of healthy everyday life. That is why it is important to take good care of them. To keep a beautiful and healthy smile brush you teeth daily with good tooth paste (preferably containing xylitol) and visit your dentist regularly.
Getting rid of the chewing gum!
After you have chewed the gum for at least 5 minutes the best way to dispose of it is to wrap it in a piece of paper and put it in a waste bin.
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