Berries, especially dark-colored ones such as bilberries and black currants, help regulate blood sugar, keeping dangerous postprandial spikes at bay. This is the result of a very recent scientific research published a few weeks ago in the British Journal of Nutrition by a team of scientists from the University of Eastern Finland (Lappi et al, BJN, Nov 2020).
Black currant and bilberry are rich in anthocyanins, which are antioxidants responsible for the dark blue color of fruits. However, anthocyanins are also very powerful substances that counteract free radicals, inflammation and reduce the absorption of glucose ingested with food by interacting directly with the enzymes responsible for the digestion of carbohydrates and with the proteins used to transport glucose. The researchers observed that the beneficial effects on blood sugar can be already observed with a small serving of berries, 75 grams or 1.5 dL. In particular, 26 volunteers were recruited, divided into four groups. After a night of fasting, the volunteers were served four different breakfast preparations containing, for all four groups, the same amount of carbohydrates and sugars. The breakfast of the first group was prepared with a puree of blackcurrant and sugar, that of the second group with a puree of blackcurrant and quinoa, the third group was served a basic product without blackcurrant and the fourth, used as a control, a glass of water and sugar. All groups were then tested for blood glucose and insulin levels every fifteen minutes for three hours after the meal. What emerged was that the two groups that had received the puree prepared with black currant had lower values ??of maximum glycaemia but also of released insulin. This therefore indicates that black currant has managed to attenuate the body's glycemic response and to improve insulin sensitivity. This effect, in the long term, can help counter the development of type 2 diabetes.