A mixture of inositol derivatives in which a sugar is bonded to inositol includes an inositol derivative (A10) in which total sugars bonded to one inositol molecule is 10 or more in terms of monosaccharide units. In addition, a mixture of inositol derivatives in which a sugar is bonded to inositol includes 5% by mass or more of an inositol derivative (A7), in which total sugars bonded to one inositol molecule is 7 or more in terms of monosaccharide units, with respect to a total amount of inositol derivatives (100% by mass).