The article, published in the peer-reviewed open access International Journal of Dentistry, was written by Peter de Cock, Global Nutrition Innovation Leader, Cargill, with the help of dentistry experts and a toxicologist. The goal, De Cock said, was to bring together all of the various branches of erythritol research into a coherent whole. Cargill is a major supplier of the ingredient, which it markets under the Zerose brand name, and it also blends it with stevia in its various Truvia offerings.
“We have done quite a bit of research ourselves, and there is other research, so we thought it was a good idea to collect what’s out there,” De Cock told NutraIngredients-USA.
The study cited a plethora of research on the effects of sugar alcohols on oral health. There is considerable murk in this area, because of the many studies done with small or slightly larger numbers of subjects, and of varying length, and with different dosages and delivery formats. De Cock and his co-authors tried to separate the wheat from the chaff.
“We were diligently looking into how those studies were done so that we could really understand under what conditions you could expect benefits from the polyols. In some cases the dosage might have been too short, or the duration too short to show a benefit for erythritol,” he said.
New evidence for old ingredient
Erythritol, a non-nutritive sugar alcohol, is not a new ingredient. It has been around for decades, and has some attractive properties in food applications. It provides a welcome bulking property in zero calorie and low calorie sweetener applications, something that stevia does not, and helps solve the problem of how to deal with this missing aspect of sugar once you take the sugar out. It also provides some of the browning properties that sugar does. And it has a taste and a sweetness profile that is closer to sugar than is stevia or monk fruit, though it is not nearly as sweet from a technical standpoint. But it is a potentially expensive ingredient, which has limited its uptake in the food realm, though Cargill has had good success with its Truvia formulations.
Another big application of sugar alcohols has been in confectionary formulations, where until recently xylitol has reigned supreme in chewing gum applications. Erythritol is something of a Johnny-come-lately to this game. Fully artificial sweeteners are used here too, of course, but having a more natural alternative is attractive for some marketers.
De Cock said that much of the research on xylitol was done using gum as the delivery mode, which adds a potentially confounding factor to the results. The act of chewing gum stimulates salivation, more so than just about anything else a person can do, and prolific salivation is a good thing in and of itself in preventing the formation of dental plaques that promote dental caries. De Cock said the aim of the paper, and of some of Cargill’s own recently published and ongoing research, is to try to separate out what can be attributed to the action of the sugar alcohols and what can be chalked up to abundant saliva.
Tearing down the lattice
The formation of oral biofilms is similar in many ways to the formation of biofilms eleswhere in the body. The bacteria gather together, communicate with each other via quorum sensing, and secrete substances that adhere to their outer surfaces that make them stick to each other and to the teeth and provide a lattice-like structure to the mature biofilm. Erythritol, the authors said, has shown the ability to prevent the “polymerization of free glucose and fructose into glucans and fructans, respectively, which, in turn, act as an energy source and protective barrier against bacterial toxins and are involved in promoting adhesion of bacteria to dental surfaces.”
Among the research cited in the paper is a long-term study supported by Cargill and conducted by researchers in Finland, which followed a large cohort of children through a long term intervention. De Cock said this research was unique because it was the only trial to use erythritol as a standalone sweetener. Other trials have tended to use it in concert with either xylitol or sorbitol. These type of studies are difficult, costly and time-consuming, De Cock said, so it’s no surprise that there are few of them to point to. Prevention of dental caries is not something that is apparent is six to twelve weeks. The study was also unique in that it delivered the sugar alcohols in the form of hard candies. This still gave the exposure duration that is needed for the erythritol to coat the teeth, but does not stimulate salivation nearly as lustily as gum does.
“A caries study needs to take at least two years, preferably three years. You need to follow a large group of people for a long time. We looked at how plaque grows and how fast it grows,” De Cock said.
Another end point that the researchers looked at, and one far easier to measure, is how many treatments the children received. The erythritol group on average had one few treatment occasion per year, a strong indication that the yearly checkup found nothing to follow up on.
Future research
De Cock said future research on erythritol in connection with dental health will delve into how it affects the overall oral microbiome. Making it harder for harmful organisms such as S. mutans to form biofilms and proliferate on the teeth should presumably lower the overall plate counts of these strains within the mouth. But as in the case of the microbiome of the human gut, the understanding of population dynamics is still in its infancy. What a healthy oral microbiome should look like, what species should be resident and in what relative proportions, is still something of a mystery, De Cock said.
Source: International Journal of Denistry
Accepted 13 July 2016
Authors: P De Cock, et al