Composition based on an aqueous extract of Nigella sativa, for use thereof as a pharmaceutical or dietetic composition for inhibiting the intestinal absorption of sugar, and treating conditions which are related thereto. According to the invention, this composition may, in addition, comprise an aqueous extract of at least a second plant derived from the following group: Olea europaea leaves, Catharanthus roseaus leaves, Salvia officinalis leaves, Gallega officinalis leaves, Juglans regia leaves, Eucalyptus globulus leaves, Trigonella foenum-graecum seeds, Sclerocarya birrea bark or leaves, Phyllantus amarus leaves. Formulation of the product BioDiabetine, comprising a combination of aqueous extract of Nigella sativa and of Olea europaea.
