Fluoride bioavailability — Nutritional and clinical aspects

The effect of non-fluoride factors on risk of dental fluorosis: Evidence from rural populations of the Main Ethiopian Rift

“…This is in agreement with the results of multiple studies in which DF has been described as a disease that begins from birth, when uptake of F − by human skeleton is the highest (Ozsvath, 2009;Whitford, 1999). About half of the absorbed F − is quickly incorporated into developing bone and teeth, where nearly all of the body's F − is found, and the remainder is excreted in the urine (Cerklewski, 1997). Exposure to F − during enamel development causes a dose-related disruption of enamel mineralization resulting in anomalously large gaps in its crystalline structure, excessive retention of enamel proteins, and increased porosity of the teeth (Aoba and Fejerskov, 2002).…”

“…Among the explanations for these results could be the competitive relationship between Ca (which is present in milk) and F − during the formation of tooth enamel, or alternatively decreased absorption of F − from the gastrointestinal tract in the presence of milk. In other studies, it has been shown that a variety of dietary factors can either increase or decrease the amount of F − that is absorbed (Cerklewski, 1997;Cremer and Büttner, 1970): for example, when Ca, Mg, Al salts, phosphates, sulfates, and Mo were added to the diet, F − was incorporated into less soluble compounds that can be eliminated through fecal and urinary excretion (Ericsson, 1968;Whitford, 1994).…”

The levels of trace elements and selected vitamins in goats with chronic fluorosis

“…In bones, fluorides alter mineralization and remodeling of bone by replacing hydroxyapatite in the bone crystalline structure. Additionally, locomotor function and nutrition may be disrupted due to reduced feed intake (9,10). In addition, Bouaziz et al (11) reported that excessive F can induce a decrease in serum levels of nonenzymatic antioxidants such as some dietary minerals such as zinc and copper, known to be cofactors of superoxide dismutase.…”

Fluoruro en alimentos: contenidos, bioaccesibilidad y absorción por el epitelio intestinal.

“…Los escasos estudios existentes sobre el transporte de fluoruro a nivel intestinal presentan resultados contradictorios en cuanto a la influencia del pH, si bien se han realizado en modelos muy distintos (Nopakun y Messer, 1990;He y col., 1998 Cerklewski, 1997).…”

“…Atendiendo a los criterios de distintos autores (Artursson y Karlsson, 1991;Yee, 1997), se podría considerar que en presencia de sales biliares el fluoruro en disolución acuosa tiene una alta absorción, y por lo tanto un comportamiento similar al observado en animales de experimentación y humanos. El ácido taurocólico disminuye la RET y aumenta el paso de LY, por tanto produce una apertura de las uniones intercelulares tal y como ya han puesto de manifiesto otros autores (Meaney y O'Driscoll, 1999 , disminuyendo su absorción intestinal (Cerklewski, 1987(Cerklewski, , 1997 influya negativamente en la bioaccesibilidad, tal y como se ha evidenciado en el capítulo 3, y por lo tanto en la biodisponibilidad del fluoruro. De hecho, concentraciones similares de Mg +2 en la dieta (>200 mg/kg) conllevan una reducción de la absorción de fluoruro en ratas (Cerklewski, 1987 Se ha analizado el efecto de exposiciones repetidas en el tiempo sobre la expresión de genes relacionados con la diferenciación celular y la estructura y permeabilidad de la monocapa epitelial.…”