Why it matters
The excessive consumption of sugary drinks and ultra-processed foods, rich in sugar, in saturated fats promote the increase in waist size and the development of non-alcoholic fatty liver disease (NAFLD) which corresponds to an infiltration of the liver by fats. NAFLD can then progress to non-alcoholic steatohepatitis (NASH), which is accompanied by inflammation and fibrosis. Although the risk of the disease increases with age, children are not spared from the NAFLD. Dietary modifications are essential to reverse or prevent the disease.
It is known that a high consumption of sugar largely contributes to the development of NAFLD. What if we replace sugars with sweeteners? In a new study published in the journal Scientific Reports, researchers wanted to answer this question and studied the effect of two sweeteners – stevia extract and sucralose – on the liver. Researchers chose these two sweeteners, which are widely used and found in many “sweet” foods.
The researchers used 5 groups of mice: a first control group with a classic diet and water and the other 4 groups with a diet high in fat and differences in carbohydrate and sugar intake. One group had plain water, another was rich in carbohydrates (water containing sucrose and fructose), another was water with sucralose and finally the last group was water and stevia.
The results show that the use of a stevia extract instead of sucrose and fructose has a beneficial effect on markers of fatty liver disease – notably fibrosis and the level of fats in the liver – and improves the fasting blood sugar and insulin sensitivity. The study also revealed some potential mechanisms that could be responsible for the reversal of these markers of fatty liver disease. Researchers have found fewer signs of cell stress and changes in the gut microbiota, both of which may explain the beneficial effects of stevia extract in controlling fatty liver disease. The use of sucralose did not show the same beneficial effects even if this sweetener improved certain markers compared to the diet with sucrose and fructose.
The gut microbiota plays a role in the genesis of NAFLD and NASH. However, the microbiota is largely influenced by our diet. Researchers point out that stevia is not absorbed from the gut and that its influence on the microbiota is likely to play an important role in the metabolic and hepatic improvements seen with stevia.
Stevia extract is a natural sweetener which a priori does not pose a health risk unlike chemical sweeteners, and in particular sucralose which is not harmless, far from it. Stevia can therefore represent an interesting alternative to control its sugar intake. By acting on glucose metabolism, Stevia extract could limit liver damage and the progression of NAFLD, if the results of this study are confirmed in humans.
In addition, it is advisable to prevent or reverse fatty liver disease to avoid foods with a high glycemic index and to practice regular physical activity.