We know more and more about sweeteners. And they no longer seem as innocuous as we always believed

One night in 1879 and while having dinner, Constantine Fahlberg he realized that the muffin he had just bitten into was incredibly sweet. But much. At first she thought the baker had been wrong, but then, taking another bite from another part of the bun, she found that the taste was normal. What was happening? Well, that Russian chemist who worked at John Hopkins University had not washed his hands when he left the laboratory and, by pure chance, he has just discovered saccharin.

Since then, the promise of non-nutritive sweeteners (“all the sweetness and none of the calories“) has been a constant.

Are those sweeteners really inert?. The key to these chemicals was precisely that they were thought to be inert in the body; that is, they had no effect on him. We felt the taste, but nothing more: as they entered, they left. The problem is that many researchers have long suspected that this is not the case. The idea that non-nutritive sweeteners are fattening is almost an urban legend: a much repeated story, but with little scientific evidence behind it.

To be precise, in many cases, it is not only that there is a lack of studies on whether these types of sweeteners are fattening; is that, being inert, it was not known how they could do it (beyond some undefined psychological mechanisms). Now, a team from the Weizmann Institute of Sciences and the German National Cancer Center have discovered how at least two of these sweeteners can affect us.

How they did it?. The approach is curious: the researchers searched 120 people who did not consume (quite strictly) non-nutritive sweeteners, they divided them into groups so that some continued without consuming these sweeteners and others began to do so. Later, to avoid problems, the researchers transferred microbial samples from those people into mice raised in completely sterile conditions (ie, without gut microbes).

And what did they discover? “The results were quite surprising,” explained the lead researcher, They were Elinavinav. “When we transferred to these sterile mice the microbiome of the individuals who consumed [sacarina y sucralosa]the recipient mice developed glycemic alterations that very significantly mirrored those of the donor individuals.” This did not happen with all sweeteners: only with saccharin and sucralose. Namely, they found that “changes in the microbiome in response to human consumption of non-nutritive sweeteners can, on occasion, induce glycemic changes in consumers in a highly personalized manner.”

The ultimate consequences of these glycemic changes are not very clear, really; but it does seem clear that we must begin to assume that these sweeteners will be many things, but not inert. Francis Guarnerdirector of the Digestive System Research Unit at the Vall d’Hebron University Hospital, it said in SMC Spain that “only one acceptable conclusion, which is also important: the fact that a substance is not absorbable and therefore does not pass into the blood, does not mean that it is inert. The substance influences the microbiota of the large intestine and can induce positive or negative changes. Everything else, despite matching with other recent studiesis still controversial.

But I shouldn’t. And it is that many parts of the world have been consuming large amounts of these products for years; something that makes the little research that we have managed to accumulate on the subject unjustifiable. Not even this study gives us a global view of the matter. As Ascención Marcos pointed outCSIC researcher, “this is a good study. However, as usual, you can always see ‘snags’. Of the 19 sweeteners approved in the EU, only four appear in this article, so no one can be extrapolated result”.

Image | Alexander Gray