Everyone likes a dessert, it cannot be denied. And with the increase in cases of obesity and diabetes, the use of sweeteners, such as aspartame, stevia or saccharin, capable of bringing the sweetness of sugar to the food but with a reduced amount of calories and without weighing on blood sugar, really seemed the optimal solution. But things are not quite like that. In fact, many of the sweeteners commonly used in the preparation of snacks, sweets and candies have been shown not to be harmless but to act by modifying the intestinal microbiota and altering blood sugar. This emerges from a very recent scientific research that appeared in the Cell magazine thanks to the work of an Israeli team (Suez et al, Cell, Aug 2022).
Sweeteners and microbiota, the first studies
Already in 2014 the scientists led by Dr. Elinav had observed that, in mice, the intake of sweeteners altered the intestinal microbiota, which is the set of bacteria that populate the intestine and that determine good functioning of the digestive system, but also of the immune system, brain and lungs. Not only that, the researchers also observed that this change in the intestinal microbiota also led to alterations in the glycemic response. What emerged immediately seemed to scientists too important to be ignored and so, years later, the same researchers studied the effect of sweeteners on humans.
The effects of sweeteners on humans
The researchers thus recruited 120 people who, before the study, had never taken sweeteners in their daily diet. For two weeks, the volunteers were asked to integrate a sweetener into their diet, such as aspartame, stevia, saccharin or sucralose, in quantities much lower than the daily limits recommended by the guidelines. Well, after the two weeks all the sweeteners had altered the gut microbiota of the volunteers. Not only that, two of these sweeteners, saccharin and sucralose, had also impaired glucose tolerance and increased blood sugar. To further confirm the link between sweeteners, changes in the microbiota and increase in blood sugar, the scientists transferred some bacteria from the human gut microbiota that were altered following the ingestion of sweeteners into the microbiota of mice. Well, all the mice developed an alteration in blood sugar.
It is therefore necessary to be careful and not to take large quantities of sweeteners thinking they are inert. In fact, they are not. Indeed, sweeteners can alter our bacterial flora, on which the health of the whole body depends, and increase blood sugar. However, sugar should also be limited as large amounts of this substance are associated with cardiovascular disease, diabetes and cancer. And taking in a lot of sugar is very easy, just count the teaspoons of sugar added to the coffees drunk during the day or how much sugar can be contained in many ready-made foods we buy. We can then begin to get used to genuine flavors, without covering them with large amounts of sugar and resorting to spices and fruits that can add sweetness without causing dangerous alterations to our microbiota, such as dates added to the dough for cakes, apples for jam or cinnamon on yogurt.