Turku Sugar Studies

Xylitol and other natural sweeteners were tested extensively in Finland as potential replacements for sugar during the early 1970’s. A series of over 20 research reports (edited by Professors Arje Scheinin and Kauko Makinen) was published together in Acta Odontologica Scandinavica, Supplement 70, in 1975. These investigations became known collectively as the “Turku Sugar Studies.”

Sweeteners were tested for their effects on dental and general health. The main trials involved the long-term substitution of either fructose or xylitol for sucrose (ordinary table sugar). This involved a huge cooperative effort between scientists and food producers. Separate fructose and xylitol versions of common food items were provided for the volunteers.

These trials (including blood and urine tests) established the safety of relatively large amounts of xylitol (often 70 grams per day or more) consumed regularly over a period of years. The xylitol group reported that xylitol-sweetened foods were comparable to the familiar sugar flavors.

The control group who consumed normal amounts of sugar continued to experience tooth decay, as would be expected. The fructose group also continued to have tooth decay, although progression appeared to be somewhat slower.

The results of a xylitol diet on oral health were dramatic. New tooth decay was practically eliminated. A therapeutic remineralizing effect was noted where the decay process was reversed. A parallel study achieved similar 90% reduction in tooth decay simply by adding a small amount of xylitol, delivered in chewing gum after meals) to a normal (regular sugar) diet.

Here are some of the major findings of the Turku Sugar Studies:

• Xylitol can be incorporated into a wide variety of food items to directly replace sugar. More than 100 different products were made with xylitol.
• The taste and overall quality of the xylitol products was comparable, and in some cases superior, to regular sugar items.
• Substantial amounts of xylitol can be consumed regularly with no adverse health effects.
• No potentially damaging bacterial adaptations to xylitol occurred.

Especially early on, there were some instances of gastrointestinal discomfort and even osmotic diarrhea in the xylitol group. After a short period of adaptation (few weeks), these symptoms diminished and became no more frequent than in the other groups. A few individuals were more sensitive than the rest of the group. Even exceptionally high intakes of xylitol of over 200 grams in a day did not necessarily cause any problems. Discomfort was more likely to occur with liquid ingestion on an empty stomach.

It is not necessary to eliminate sugar to dramatically reduce tooth decay. Similar results can be obtained simply by adding a small amount of xylitol to a “normal” diet. Xylitol can provide a natural “antidote” for the damaging dental effects of ordinary sugar. A little more that a teaspoon of xylitol per day can provide amazing protection against tooth decay, when used in chewing gum after meals and snacks.

The Turku Sugar Studies opened a new direction for safe, natural, convenient, and enjoyable protection from tooth decay. This approach was rapidly adapted in Finland, where xylitol chewing gum was successfully incorporated into a comprehensive approach to improve dental public health.

--by Dr. John Peldyak