[Biological availability of fluoride after combined administration with vitamin D3 in man (author's transl)]

Six adults ingested 1 mg fluoride, first as NaF in a watery solution and, secondly, in tablet form (D-Fluoretten 1000). Fluoride concentration was almost identical in the two series. After initial values within the normal range concentrations rapidly rose to a maximum (six times normal) reached on average after 30 minutes, followed by an, at first steep then more gradual, fall in concentration over eight hours. The area under the curve was similar in the two series. These results indicate that the biological availability of fluoride is not influenced by vitamin D3 in the adult and, presumably, in the small child as well.