A calcium receptor activator containing one or more kinds of substances selected from á-Glu-Cys-Gly, á-Glu-Cys(SNO)-Gly, á-Glu-Ala, á-Glu-Gly, á-Glu-Cys, á-Glu-Met, á-Glu-Thr, á-Glu-Val, á-Glu-Orn, Asp-Gly, Cys-Gly, Cys-Met, Glu-Cys, Gly-Cys, Leu-Asp, D-Cys, á-Glu-Met(O), á-Glu-Val-Val, á-Glu-Val-Glu, á-Glu-Val-Lys, á-Glu- á-Glu-Val, á-Glu-Val-NH2, á-Glu-Val-ol, á-Glu-Ser, á-Glu-Tau, á-Glu-Cys(S-Me)(O), á-Glu-Leu, á-Glu-Ile, á-Glu-t-Leu, á-Glu-Cys(S-allyl)-Gly, á-Glu-Gly-Gly, á-Glu-Val-Phe, á-Glu-Val-Ser, á-Glu-Val-Pro, á-Glu-Val-Arg, á-Glu-Val-Asp, á-Glu-Val-Met, á-Glu-Val-Thr, á-Glu-Val-His, á-Glu-Val-Asn,á-Glu-Val-Gln, á-Glu-Val-Cys, á-Glu-Val-Orn, á-Glu-Ser-Gly, á-Glu-Cys(S-Me), á-Glu-Abu-Gly, á-Glu-Cys(S-Me)-Gly, and á-Glu-Val-Gly.