Xylitol – soap for the nose.

It is classed as a "sugar alcohol," but properly it is neither a sugar nor an alcohol. It looks like sugar; it tastes like sugar. But it is O.K. for diabetics. A molecule of xylitol (without all of the hydrogen atoms) looks like the model in the picture at the top, but it is very flexible.

It is commonly used as a food supplement because of its natural sweetness. The World Health Organization and the FDA (Sec. 172.395 (21 CFR 172.395)), have given it safe ratings as food supplements. It is commonly available commercially without restriction and is found in many health food stores.

It is made in the human body. An average sized person makes about 10 grams of xylitol every day.

Xylitol is slowly absorbed when eaten and if a person eats more than a teaspoon or so at one time they are likely to have a few loose stools, just like what happens with sorbitol, the most commonly used of the sugar alcohols.

• People who use xylitol regularly learn to deal with it better and it doesn't cause this problem.
• People in Turku, Finland ate about one-fourth cup daily in a dental study and had no significant problems.

The xylitol that is absorbed is rapidly metabolized, but it has very little effect on blood sugar levels. Asano and his associates looked at this in the early 70’s when xylitol was being considered for use in diabetics. He gave healthy people 5 grams of xylitol, but could not detect any in their blood an hour later.

Xylitol costs about ten times as much as regular sugar. If there is more demand I am sure that price will come down. I think this is one reason it is not used more. With the current epidemic of diabetes, due in large part to the combination of inactivity and sugar heavy soft drinks, xylitol is a very attractive food supplement.

Xylitol is available in some countries in IV solutions. It is used in diabetics and in some critical care situations such as burns. In papers prepared for the FDA the usual IV dose is 0.25 grams per kilogram per hour and the safe dose is double that. For a 154 pound person that is the equivalent of about 800 to 1600 plums a day.

The glycemic index of xylitol is 7. The glycemic index is a measure of how rapidly particular foods are turned into glucose after we eat them and of how much insulin is required for the body to use that food. It is useful information for diabetics and many can control their diabetes just by not eating foods with a high glycemic index. If you are interested in more information about the glycemic index this link will take you to Rick Mendosa's web page which has the best information I have found on the web.

Xylitol is interchangeable with sugar for most cooking applications. Yeast cannot metabolize it so it won't work if you are baking bread or anything else with yeast. (Doctors inclined toward natural treatments have recommended the use of xylitol to prevent yeast infections for this reason.)

About twenty years after the war they realized that the people who used xylitol had less tooth decay. The Turku Sugar Studies, done at the University of Turku, confirmed this observation:

The results of this study were exciting to the Finns and they increased their use of xylitol. They also did more studies. One of the things they did that made both of these easier was making gum with xylitol. Chewing the gum releases the xylitol over a short period of time in the mouth where it is effective. Most of the studies on tooth decay since that time have used gums as the delivery because it is easy to dose and to measure how much is given (and because they were funded by the company making the gum. The web site at www.xylitol.net is maintained by the company manufacturing the gum in Finland and has a lot of information about this and other uses of xylitol.

John Peldyak was involved with some of the studies looking at xylitol and tooth decay done through the University of Michigan Dental School. He recently summarized the studies with this gum and the prevention of tooth decay—regular frequent use is the key. Chewing xylitol flavored gum once a day had little benefit. Twice a day reduced cavities by 40%, three times a day by 60% and by chewing this gum five times a day cavities were reduced by more than 80%. The chart below is Dr. Peldyak's summary of eleven clinical studies showing how well xylitol does at preventing tooth decay.

Tooth decay is caused by bacteria, Streptococcus Mutans (S. Mutans) is the main one, that live in the mouth and on the teeth. These bacteria actually build the plaque that is on the teeth; it is their home. They take sugar (glucose) from the food we eat and metabolize it. In the process they make an acid that eats through the enamel surfaces of our teeth. This is the beginning of a cavity.

• The bacteria eat the xylitol, but can’t use it, so they have to get rid of it. This takes energy and gives the bacteria what we humans experience as indigestion.
• It also blocks the ability of these bacteria to hold on to the surfaces in our bodies. They can hold onto the plaque, that is their home, but they have a harder time holding on to the host cells. This is an important concept and will be discussed further in a page about how such sugar-like foods effect bacteria and infection—it's part of a science called glycobiology. The additional research on xylitol's effect on S. mutans will be discussed there as well.

After another 20 years of increased use the Finns also found that xylitol decreased ear infections. Matti Uhari's group in Oulu, Finland studied this and reported their findings in the British Medical Journal in 1996; and in Pediatrics in 1998, where they used a syrup for those too young to chew gum. 

• They showed that ear infections in children could be reduced by up to 40% with 8-9 grams of oral xylitol every day.  
• Both the prevention of tooth decay and the reduction of the ear infections are by interactions of xylitol with the bacteria—in the mouth where they cause tooth decay, and in the nose where they cause ear, sinus, and bronchial infections.

Uhari’s group  looked at what happened when the bacteria in the nose were exposed to xylitol. 

•     The three main problem causing bacteria that frequently colonize the nose  are Streptococcus Pneumoniae (S. Pneumo.), Haemophilus Influenzae (H. Flu.), and Moraxella Catarrhalis (M. Cat.). 

• The nose is the only place they live without causing infection. The back of the nose is called their reservoir.   

• S. Pneumo. got indigestion from the xylitol, and so, to a lesser extent, did beta strep, the bacteria that cause strep throat.  This is not surprising because they already knew that this was the effect on S. Mutans and  these bacteria belong to the family of streptococci and are closely related. All of the studies done comparing the effect of xylitol on S. Mutans and S. Pneumoniae show similar effects. 

  •    Bacterial indigestion was the reason they gave for the decrease in ear infections.

  • Remember that in these studies the xylitol was given orally. That means that the xylitol had to get absorbed into the blood and carried back to the nose where the bacteria live.

  • That's not very effective—One American doctor figured that a child would have to chew close to a thousand pieces of gum at a cost of about $100.00 to prevent one ear infection.

    •       Either he was exaggerating or the price of the gum has come down. It's only about $40.  

But it works much better than that when it is put in the nose, where the bacteria live, and it works in other ways as well.

• The Finnish doctors did another study that was reported in between the two on ear infections. In this study, the group, led by Tero Kontiokari, looked at how xylitol effected the adherence of the major problem bacteria to cells from the nose. 

• Bacteria must hang on to cells in the nose (or anywhere else for that matter) in order to cause infection—if they cannot hold on they are washed out and don't cause problems.  

• This study looked at that adherence.

• They took cells from the nose and several strains of the bacteria that cause most of the infections. Dividing each into two groups they put a 5% solution of xylitol in one group of the cells and the bacteria. 

• Then they put the different groups together, let them sit for a while then spun them to get rid of unattached bacteria. 

• Finally, they actually counted the bacteria attached to each cell. The graph shows what they found.

• The 68% decrease in the adherence of S. Pneumo shows it to be the most sensitive to the presence of xylitol. This is probably why they only saw a 30-40% reduction in ear infections. That is about the percent caused by S. Pneumo. Giving xylitol by mouth is not a very effective means of getting it to the nose because it must be absorbed into the blood then carried to the nose, but even the small amount getting there was able to effect these bacteria. 

There are several important things about this study:

• These are significant bacteria—they kill people. 

• The Center for Disease Control (CDC) estimates that infections with S. Pneumo cause the death of more than 40,000 people every year in the U.S. with many of them being infants and small children. 

• They cost our health care system billions of dollars every year, to say nothing of the countless days of lost work due to personal or family illness.

• These are the bacteria that are the primary reason for prescription antibiotics and those prompting concern about antibiotic resistance.

• Xylitol, a food substance, reduces the adherence of these bacteria – and without this adherence there is no infection.

• It focuses on the inside of the nose. Because of Asano’s study showing that xylitol is rapidly removed from the blood stream we can tell that giving xylitol orally is not a very good way to get reasonable amounts to the bacteria living in the nose.

• Finally it shows that the indigestion model is not a sufficient explanation for the reduced adherence. If the effect were only on the bacteria the arm of this study where the cell, but not the bacteria, was exposed to xylitol would not have been as effective.  But the reduction in adherence was not significantly different. In fact adherence was less (21 vs. 25) when the cells were exposed to the xylitol. So its most likely place of action is the interface between the cells and the bacteria. This interface is the subject of the page dealing with glycobiology.

At the end of this study Kontiokari states the following:

"These observations are consistent with the fact that monosaccharides are able to inhibit adherence only at high concentrations that are easily achieved in the oral cavity."

Notice two things here:

• High concentrations are needed. If high concentrations are needed in the nose the best way to get them is to put it there – just like the gum puts it in the mouth.
• He did not specify xylitol, but implied this was a property of monosaccharides (sugars) in general.  

What he is referring to is the fact that several other sugars share this ability to interfere with bacterial adhesion. 

Again if bacteria cannot adhere, hold on to our cells, they can't infect us. Is this a way to prevent infections? YES! Read more in the section on glycobiology.

Return to HOME                   Continue with GLYCOBIOLOGY

References:

Diabetes 1973 Apr;22(4):279-81

Xylitol absorption in healthy men.

Asano T, Levitt MD, Goetz FC

PMID: 4696096

Am J Clin Nutr 1997 Apr;65(4):947-50

Metabolic response to lactitol and xylitol in healthy men.

Natah SS, Hussien KR, Tuominen JA, Koivisto VA

Helsinki University Central Hospital, Department of Medicine, Finland.

Sugar alcohols are used in food products, yet their metabolic effects in humans are poorly known. We examined plasma glucose, insulin, and C-peptide responses and changes in carbohydrate and lipid oxidation after the ingestion of 25 g lactitol, xylitol, or glucose. Eight healthy, nonobese men were studied after an overnight fast. After the ingestion of lactitol or xylitol, the rise in plasma glucose, insulin, and C-peptide concentrations was less than after the ingestion of glucose (P < 0.02), with no difference between the two polyols. With the glycemic index of glucose as 100, the indexes of xylitol and lactitol were 7 and -1, respectively. A reactive hypoglycemia was observed 3 h after glucose ingestion, but not after the ingestion of sugar alcohols. There were no significant changes in the carbohydrate or lipid oxidation as determined by indirect calorimetry after the ingestion of sugar alcohols. After glucose ingestion, the rise in carbohydrate oxidation was nearly significant (P = 0.07). In conclusion, lactitol and xylitol cause smaller changes than does glucose in plasma glucose and insulin concentrations and thermogenic response. A small hormonal response and the lack of a thermogenic effect may be beneficial when these sugar alcohols are used in food products. The small glucose and insulin responses also suggest that lactitol and xylitol are suitable components of the diet for diabetic patients.

Publication Types:

Clinical trial

Randomized controlled trial

PMID: 9094877

Acta Odontol Scand 1976;34(4):179-216

Turku sugar studies. V. Final report on the effect of sucrose, fructose and xylitol diets on the caries incidence in man.

Scheinin A, Makinen KK, Ylitalo K

The purpose was to study differences in the caries increment rate as influenced by various sugars. The trial involved almost complete substitution of sucrose (S) by fructose (F) or xylitol (X) during a period of 2 years. There were no significant initial differences as to caries status between the prospective sugar groups; 35 subjects in the S-group, 38 in the F-group, and 52 in the X-group. During the entire study 10 subjects discontinued or were excluded. The clinical and radiographical observer error was reported and discussed. After 2 years the mean increment of decayed, missed and filled tooth surfaces was 7.2 in the S-group, 3.8 in the F-group, and 0.0 in the X-group. The weakness of the DMFS-index in not showing the development of new secondary caries and the increase in size of the lesions was overcome by expressing the caries activity in terms of indices showing the total quantitative and qualitative development. The results showed a massive reduction of the caries increment in relation to xylitol consumption. Fructose was found to be less cariogenic than sucrose. It was suggested that the non- and anticariogenic properties of xylitol principally depend on its lack of suitability for microbial metabolism and physico-chemical effects in plaque and saliva.

Publication Types:

Clinical trial

Randomized controlled trial

PMID: 795260

Antimicrob Agents Chemother 1995 Aug;39(8):1820-3

Effect of xylitol on growth of nasopharyngeal bacteria in vitro.

Kontiokari T, Uhari M, Koskela M

Department of Pediatrics, University of Oulu, Finland.

Xylitol is known to reduce caries by inhibiting the growth of Streptococcus mutans. We hypothesized that xylitol could also affect the growth of other nasopharyngeal bacterial flora, which could be important when considering respiratory infections caused by these bacteria. We studied this in vitro by adding xylitol to the medium and observed that 1 and 5% xylitol reduced markedly the growth of alpha-hemolytic streptococci, including S. pneumoniae. It reduced slightly the growth of beta-hemolytic streptococci but not that of Haemophilus influenzae or Moraxella catarrhalis. The inhibitory growth pattern was similar to that previously seen with S. mutans, which may indicate a similarity in the enzymatic processing of five-carbon sugars such as xylitol. This sugar alcohol is a widely used sweetener, and the concentrations used in our experiments are easily achieved in the oral cavity. If xylitol reduces the growth of S. pneumoniae in the nasopharynx, it could also reduce the carriage of this pathogen and thus have clinical significance in the prevention of pneumococcal diseases.

PMID: 7486925

: BMJ 1996 Nov 9;313(7066):1180-4

Xylitol chewing gum in prevention of acute otitis media: double blind randomised trial.

Uhari M, Kontiokari T, Koskela M, Niemela M

Department of Paediatrics, University of Oulu, Finland.

OBJECTIVE: To examine whether xylitol, which reduces the growth of Streptococcus pneumoniae, might have clinical importance in the prevention of acute otitis media. DESIGN: A double blind randomised trial with xylitol administered in chewing gum. SETTING: Eleven day care nurseries in the city of Oulu. Most of the children had had problems with recurrent acute otitis media. SUBJECTS: 306 day care children: 149 children in the sucrose group (76 boys; mean (SD) age 4.9 (1.5) years) and 157 in the xylitol group (80 boys; 5.0 (1.4) years). INTERVENTION: Either xylitol (8.4 g a day) or sucrose (control) chewing gum for two months. MAIN OUTCOME MEASURES: The occurrence of acute otitis media and antimicrobial treatment received during the intervention and nasopharyngeal carriage of S pneumoniae. RESULTS: During the two month monitoring period at least one event of acute otitis media was experienced by 31/149 (20.8%) children who received sucrose compared with 19/157 (12.1%) of those receiving chewing gum containing xylitol (difference 8.7%; 95% confidence interval 0.4% to 17.0%; P = 0.04). Significantly fewer antimicrobials were prescribed among those receiving xylitol: 29/157 (18.5%) children had at least one period of treatment versus 43/149 (28.9%) (difference 10.4%; 0.9% to 19.9%; P = 0.032). The carriage rate of S pneumoniae varied from 17.4% to 28.2% with no difference between the groups. Two children in the xylitol group experienced diarrhoea, but no other adverse effects were noted among the xylitol users. CONCLUSION: Xylitol seems to have a preventive effect against acute otitis media.


PMID: 8916749

Pediatrics 1998 Oct;102(4 Pt 1):879-84

A novel use of xylitol sugar in preventing acute otitis media.

Uhari M, Kontiokari T, Niemela M

Department of Pediatrics, University of Oulu, Oulu, Finland.

BACKGROUND: Xylitol, a commonly used sweetener, is effective in preventing dental caries. As it inhibits the growth of pneumococci, we evaluated whether xylitol could be effective in preventing acute otitis media (AOM). DESIGN: Altogether, 857 healthy children recruited from day care centers were randomized to one of five treatment groups to receive control syrup (n = 165), xylitol syrup (n = 159), control chewing gum (n = 178), xylitol gum (n = 179), or xylitol lozenge (n = 176). The daily dose of xylitol varied from 8.4 g (chewing gum) to 10 g (syrup). The design was a 3-month randomized, controlled trial, blinded within the chewing gum and syrup groups. The occurrence of AOM each time the child showed any symptoms of respiratory infection was the main outcome. RESULTS: Although at least one event of AOM was experienced by 68 (41%) of the 165 children who received control syrup, only 46 (29%) of the 159 children receiving xylitol syrup were affected, for a 30% decrease (95% confidence interval [CI]: 4.6%-55.4%). Likewise, the occurrence of otitis decreased by 40% compared with control subjects in the children who received xylitol chewing gum (CI: 10.0%-71.1%) and by 20% in the lozenge group (CI: -12.9%-51.4%). Thus, the occurrence of AOM during the follow-up period was significantly lower in those who received xylitol syrup or gum, and these children required antimicrobials less often than did controls. Xylitol was well tolerated. CONCLUSIONS: Xylitol sugar, when given in a syrup or chewing gum, was effective in preventing AOM and decreasing the need for antimicrobials.


PMID: 9755259

J Antimicrob Chemother 1998 May;41(5):563-5

Antiadhesive effects of xylitol on otopathogenic bacteria.

Kontiokari T, Uhari M, Koskela M

Department of Paediatrics, University of Oulu, Finland.

The exposure of either epithelial cells or pneumococci or both to 5% xylitol reduced the adherence of pneumococci. Exposure of epithelial cells or bacteria alone to xylitol did not reduce the adherence of Haemophilus influenzae, although the exposure of both cells and bacteria to xylitol reduced the adherence significantly. The adherence of Moraxella catarrhalis remained low irrespective of the exposure.

PMID: 9630410

J Dent Hyg. 2002 Fall;76(4):276-85.

Xylitol for caries prevention.

Peldyak J, Makinen KK.

Institute of Dentistry, University of Turku, Turku, Finland.

Xyitol is a naturally occurring sweetener which is essentially not fermentable by the caries-inducive oral microflora. When tested as a sucrose replacer, or even as a small dietary addition, systematic xylitol use leads to impressive reductions in caries incidence. Xylitol is compatible and complementary with all current oral hygiene recommendations. The appealing sensory and functional properties of xylitol facilitate a wide array of applications that promote oral health.