Xylitol

Xylitol (also known as xylite, birch sugar, koivusokeri) (CH₂OH(CHOH)₃CH₂OH) is a naturally occuring sugar alcohol found in berries, fruit, vegetables and mushrooms. For example raspberry, strawberry, yellow plum and endive (as well as human tissue) contain xylitol in small amounts. Most xylitol is extracted from birch wood.

Xylitol is slowly and only partially absorbed by the body -- this makes it an excellent sweetener candidate for diabetics. There are concerns -- see Safety Issues below. Xylitol has been shown to be anticariogenic (prevent tooth decay), reduce gingivitis (gum disease) in adults and help prevent ear infections.

Chemical Composition

  CH₂OH
  |
 HCOH
  |
HOCH
  |
 HCOH
  |
  CH₂OH

History

Discovered almost simultaneously in the late 19th Century by German and French chemists, xylitol has been used for decades as a sweetener for diabetics in Russia. In China, xylitol is used fairly extensively for medical purposes.

Xylitol-Jenkki, the first xylitol chewing gum in the world, was launched by the Finnish company Leaf in 1975. Today, xylitol can be found in chewing gums (Trident, XyliFresh), toothpaste (Arm & Hammer, Pepsodent) as well as mouthwashes and candies.

Benefits

Unlike other sweeteners (sobritol (C₆H₈(OH)₆), fructose (C₆H₁₂O₅) or glucose (C₆H₁₂O₆), for example), xylitol has five instead of six carbon atoms -- most bacterias in the mouth (including Streptococcus mutans) are unable to metabolise it. Xylitol also stimulates saliva secretion and raises the pH (lowers the acidity) of the mouth, making it less hospitable to S. mutans.

Xylitol also inhibits the growth of Streptococcus pneumoniae, a bacteria responsible for ear infections.

Dosage

Studies on the effectiveness of xylitol involved doses ranging from 4 to 10 grams daily -- this corresponds to 3 to 8 pieces of xylitol-laced chewing gum.

Safety Issues

Xylitol is believed to be safe, although daily doses higher than 30 grams can cause stomach discomfort or diarrhea. Note that other sugar alcohols carry the same caveat -- by order of the FDA, products containing a certain amount (that amount which makes it conceivable that 50 grams of sorbitol or 20 grams of mannitol may be ingested in 24 hours) must bear the warning, 'Excess consumption may have laxative effect'.

Xylitol is classified 'Miscellaneous/Food additive for which a petition has been filed and a regulation issued,' in the FDA's 2001 Investigations Operations Manual, with the comment:

[Provided that an] Amt used is not > that required to produce its intended effect -- May be safely used in foods for special dietary uses.

Source:

Xylitol FAQ:

http://www.xylitol.net/english/faq.cfm

Xylitol Study (Korean):

http://www.xylitolstudy.co.kr

Microhydron.Com:

http://www.microhydron.com/xylitol.htm

AccessScience@McGraw-Hill:

http://www.accessscience.com

Healing People -- Herbs & Supplements: Xylitol

http://www.healingpeople.com/hp_html/primapub/pg000288.htm

United States Food and Drug Administration Web Site:

http://www.fda.gov

Health & Healing

http://www.microhydron.com/xylitol.htm

Hildebrandt GH, Sparks BS. Maintaining mutans streptococci suppression with xylitol chewing gum. J Am Dent Assoc. 2000;131:909-916.

Uhari M, Kontiokari T, Niemela. A novel use of xylitol sugar in preventing acute otitis media. Pediatrics. 1998;102:879-884.

Xylitol chewing gum is given to children in schools in Finland, because it prevents cavities. It cannot be digested by oral bacteria. Formerly, there was a special candy tax, which didn't include xylitol candies. The market share of the chewing gum not containing xylitol is only 3%. Connect the dots.

Xylifresh is the only chewing gum that has got the recommendation of the Finnish Dental Association, because its only sweetener is xylitol. The recommended usage is to eat it each time after eating, which is 3-5 times a day. The xylitol will take the place of the sugars in the food, so that the bacteria don't have time to metabolize the food. Stopping the chewing of xylitol will cause the mutans streptococcus to regrow back to its original level, so that they must be suppressed continuously with xylitol. (Eating 10 pieces once a day is less effective than 2 pieces five times a day.)

The birch contains xylane, which is extracted, and so it breaks up to smaller xylosis molecules, which is converted to xylitol by adding hydrogen to it in high pressure, temperature and in the presence of a catalyst, activated nickel. This industrial process (which is dangerous and has caused explosions) makes it more expensive than the other sweeteners, so that most chewing gum manufacturers cut the xylitol with less expensive sweeteners.

The xylosis molecule has the unsaturated carbon-oxygen double bond, or the aldehyde group, in the terminal carbon, which makes it a sugar. Add hydrogen to both ends, and you'll saturate the carbon and get an alcohol. Look at the structure above: there are only saturated carbons bonded to the hydroxyl group. This is why xylitol isn't a sugar, but is easily made from a sugar.

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Sources: Hammashuolto - suositukset. http://www.riihimaki.fi/terveyskeskus/hammashuolto3.htm