ABC | Volume 111, Nº2, August 2018

Letter to the Editor Santos Phytosterols and sex hormone analysis Arq Bras Cardiol. 2018; 111(2):228-229 1. Cabral CE, KleinMR. Phytosterols in the treatment of hypercholesterolemia and prevention of cardiovascular diseases. Arq Bras Cardiol. 2017;109(5):475–82. 2. Santos HO. Ketogenic diet and testosterone increase: Is the increased cholesterol intakeresponsible?Towhatextentandunderwhatcircumstances can there be benefits? Hormones(Athens).2017;16(3):150-60. 3. Weststrate JA, Ayesh R, Bauer-Plank C, Drewitt PN. Safety evaluation of phytosterol esters. Part 4. Faecal concentrations of bile acids and neutral sterols in healthy, normalipidaemic volunteers consuming a controlled diet either with or without a phytosterol ester-envirchedmargarine. Food Chem Toxicol. 1999;37(11):1063-71. 4. Rose C, Parker A, Jefferson B, Cartmell E. The Characterization of feces and urine: A reviewof the Literature to InformAdvanced Treatment Technology. Crit Rev Environ Sci Technol. 2015;45(17):1827-79. 5. Awada AB, HartatiaMS, Finka CS. Phytosterol feeding induces alteration in testosterone metabolism in rat tissues. J Nutr Biochem. 1998;9(17):712-7. References Reply We thank you for your interest and comments related to our recent review article entitled “Phytosterols in the Treatment of Hypercholesterolemia and Prevention of Cardiovascular Diseases,” 1 which aimed specifically to address the available evidence in the literature on the association between phytosterols and risk of cardiovascular diseases. We agree that it is important to investigate the effects of phytosterols on serum levels of sex hormones, especially due to the potential risk of reducing plasma testosterone levels. We are not aware of studies carried out in humans that have performed such an evaluation. Experimental animal studies are scarce, and a reduction in plasma testosterone levels has been observed in some, 2,3 but not all of them. 4 Sincerely, Carlos Eduardo Cabral Márcia Regina Simas Torres Klein 1. CabralCE,KleinMR.PhytosterolsintheTreatmentofHypercholesterolemiaand PreventionofCardiovascularDiseases.ArqBrasCardiol.2017;109(5):475-482. 2. QasimiMI,NagaokaK,WatanabeG.Theeffectsofphytosterolsonthesexual behavior and reproductive function in the Japanese quail (Coturnix coturnix japonica). Poult Sci. 20171;96(9):3436-44. 3. Awad AB, SriHartati M, Fink CS. Phytosterol feeding induces alteration in testosterone metabolism in rat tissues. J Nutr Biochem. 1998; 9(12):712–7 4. Ryökkynen A, Käyhkö UR, Mustonen AM, Kukkonen JV, Nieminen P. Multigenerational exposure to phytosterols in the mouse. Reprod Toxicol. 2005; 19(4): 535-40. References This is an open-access article distributed under the terms of the Creative Commons Attribution License 229