Fragrant and delicious, rooibos tea, also called red tea, can become a real ally for health. In fact, in addition to its anti-obesity, antioxidant and antitumor properties, we now know that it contributes to reducing the risk of developing type 2 diabetes. This is what emerges from a very recent scientific research published in the journal Molecules by a South African team ( Mthembu et al, Molecules, 2021).
Insulin resistance, the antechamber of diabetes
Insulin resistance is a condition in which cells decrease their sensitivity to insulin. Insulin allows glucose to pass from the blood to the cell. It follows, therefore, that in conditions of insulin resistance the pancreas is required to release more insulin than normal to guarantee the same results. In the long run, however, the body is no longer able to carry out this compensation and the consequence is an increase in blood sugar. Therefore, insulin resistance can be considered the antechamber of type 2 diabetes. The main site of insulin resistance is represented by the muscles. The exact causes that lead to this dysfunction are not yet known, but it is believed that the action of free radicals can increase inflammation and thus determine insulin resistance. As proof of this statement, numerous studies have been able to observe that the intake of antioxidant substances, such as resveratrol in grape and cinnamaldehyde in cinnamon, is able to increase insulin sensitivity, thus reducing the risk of developing type 2 diabetes.
The antidiabetic action of rooibos tea
Rooibos tea is a very popular drink all over the world. This tea provides valuable antioxidants, such as aspalatin and notophagin, capable of counteracting free radical damage, inflammation, obesity and cell degeneration. A possible antidiabetic action has also been hypothesized for rooibos tea, although, to date, this has not been clearly demonstrated. To investigate the possible antidiabetic action of rooibos tea, the researchers carried out a study in the laboratory. In particular, the scientists first induced oxidative stress at the cellular level in order to alter the cell's sensitivity to insulin. They then brought the cell into contact with the antioxidants in rooibos tea. Well, what has been observed is that these antioxidants were able to reverse the process triggered by free radicals by restoring the cell to function normally. Not only that, the antioxidant action of rooibos tea was comparable to that of metformin, a drug used to treat type 2 diabetes and capable of reducing insulin resistance.
The study does not want to state that a cup of rooibos tea can take the place of some medications prescribed by the doctor to treat diabetes. But certainly, for preventive purposes, rooibos tea also finds its place in a healthy and varied diet, to improve insulin sensitivity and to reduce the risk of developing type 2 diabetes.