Peptide variants of fragment (1-34) of parathyroid hormone, in which at least one of the amino acid residues at positions 7, 11, 23, 24, 27, 28 and 31 is cyclohexylalanine, or at least one of the amino acid residues at positions 3, 16, 17, 18, 19 and 34 is α-aminoisobutyric acid; or, alternatively, at least the amino acid residue at position 1 is α,β-diaminopropionic acid, the amino acid residue at position 27 is homoarginine, or the amino acid residue at position 31 is norleucine.