RESUMO
Silicon is the second most abundant element on Earth, and the third most abundant trace element in human body. It is present in water, plant and animal sources. On the skin, it is suggested that silicon is important for optimal collagen synthesis and activation of hydroxylating enzymes, improving skin strength and elasticity. Regarding hair benefits, it was suggested that a higher silicon content in the hair results in a lower rate of hair loss and increased brightness. For these beneficial effects, there is growing interest in scientific studies evaluating the efficacy and safety of using dietary supplements containing silicon. Its use aims at increasing blood levels of this element and improving the skin and its annexes appearance. There are different forms of silicon supplements available and the most important consideration to be made in order to select the best option is related to safety and bioavailability. Silicon supplements are widely used, though there is wide variation in silicon bioavailability, ranging from values below 1% up to values close to 50%, depending on the chemical form. Therefore, the aim of this study was to evaluate the scientific literature related to the different chemical forms of silicon supplements available and the limitations and recent progress in this field. According to reported studies, among the different chemical forms available, the orthosilicic acid (OSA) presents the higher bioavailability, whereas the others forms have absorption inversely proportional to the degree of polymerization. However, clinical studies evaluating safety and efficacy are still lacking.
Assuntos
Doenças do Cabelo , Ácido Silícico/farmacocinética , Silício/farmacocinética , Envelhecimento da Pele/efeitos dos fármacos , Disponibilidade Biológica , Colágeno/biossíntese , Suplementos Nutricionais , Doenças do Cabelo/tratamento farmacológico , Humanos , Doenças da Unha/tratamento farmacológico , Ácido Silícico/uso terapêutico , Silício/deficiência , Silício/fisiologia , Silício/uso terapêutico , Compostos de Silício/farmacocinética , Compostos de Silício/uso terapêutico , Envelhecimento da Pele/fisiologiaRESUMO
Abstract Silicon is the second most abundant element on Earth, and the third most abundant trace element in human body. It is present in water, plant and animal sources. On the skin, it is suggested that silicon is important for optimal collagen synthesis and activation of hydroxylating enzymes, improving skin strength and elasticity. Regarding hair benefits, it was suggested that a higher silicon content in the hair results in a lower rate of hair loss and increased brightness. For these beneficial effects, there is growing interest in scientific studies evaluating the efficacy and safety of using dietary supplements containing silicon. Its use aims at increasing blood levels of this element and improving the skin and its annexes appearance. There are different forms of silicon supplements available and the most important consideration to be made in order to select the best option is related to safety and bioavailability. Silicon supplements are widely used, though there is wide variation in silicon bioavailability, ranging from values below 1% up to values close to 50%, depending on the chemical form. Therefore, the aim of this study was to evaluate the scientific literature related to the different chemical forms of silicon supplements available and the limitations and recent progress in this field. According to reported studies, among the different chemical forms available, the orthosilicic acid (OSA) presents the higher bioavailability, whereas the others forms have absorption inversely proportional to the degree of polymerization. However, clinical studies evaluating safety and efficacy are still lacking.
Assuntos
Humanos , Ácido Silícico/farmacocinética , Silício/farmacocinética , Envelhecimento da Pele/efeitos dos fármacos , Doenças do Cabelo , Ácido Silícico/uso terapêutico , Silício/deficiência , Silício/fisiologia , Silício/uso terapêutico , Disponibilidade Biológica , Envelhecimento da Pele/fisiologia , Colágeno/biossíntese , Compostos de Silício/uso terapêutico , Compostos de Silício/farmacocinética , Suplementos Nutricionais , Doenças do Cabelo/tratamento farmacológico , Doenças da Unha/tratamento farmacológicoRESUMO
AIMS: To assess whether there was any significant difference in the average fractional urinary fluoride excretion (FUFE) values among adults consuming (NaF) fluoridated Ca-free water (reference water), naturally fluoridated hard water and an artificially (H2SiF6) fluoridated soft water. DESIGN: Sixty adult females (N=20 for each treatment) participated in this randomized, double-blind trial. The experimental design of this study provided an indirect estimation of the fluoride absorption in different types of water through the assessment of the fractional urinary fluoride excretion of volunteers. RESULTS: Average daily FUFE values (daily amount of fluoride excreted in urine/daily total fluoride intake) were not significantly different between the three treatments (Kruskal-Wallis; p = 0.62). The average 24-hour FUFE value (n=60) was 0.69; 95% C.I. 0.65-0.73. CONCLUSIONS: The results of this study suggest that the absorption of fluoride is not affected by water hardness.