The Pharmacology of Fluoride and its contribution to Diabetes and Obesity.
- the solubility of the fluoride source,
- the concentration of fluoride in the source,
- the amount of fluoride available for absorption,
- the pH of the medium in which absorption takes place and
- the presence or absence of fluoride-insolubilizing substances.
This means fluoridation of drinking water results in greater retention of fluoride overall as water is consumed over the course of a day over a persons entire lifetime.
A factor that was identified to influence fluoride retention is the age of the subject exposed to fluoride. The younger the person the more fluoride is retained in the body.
He further observed that:
 [The Pharmacology of Fluoride BY GUSTAV W.M. RAPP, Ph.D. Reprinted from the April 1950 issue of THE BUR, REPRINT NO. 53
 Sinnott M, Carr BM, Walsh C et al. Combination of FINDRISC and fasting plasma glucose (FPG) in screening for type 2 diabetes in an Irish population: the type 2 diabetes mellitus and vascular health initiative (DMVHI). Diabetologia 2011; 54(Suppl. 1):S102.