Serum preptin and breast milk preptin were found to be lower in rachitic children and their mothers, respectively, when compared to non‐rachitic subjects.113 Serum preptin levels are decreased in both men and women with osteoporosis and positively correlate with bone mass density.114, 115 It is therefore likely that a lower activity of preptin is involved in the pathogenesis of osteoporosis, affecting bone formation rather than bone resorption. Here, IGF2 is linked to osteoporosis.