The following is a summary of “Sex Differences in Phosphate Homeostasis: Females Excrete More Phosphate and Calcium After an Oral Phosphate Challenge,” published in the 1 April 2023 issue of Endocrinology & Metabolism by Turner, et al.
The consumption of dietary phosphate is increasing, and elevated serum phosphate levels are associated with an increased risk of cardiovascular disease (CVD). Sex differences in phosphate homeostasis and response to changes in dietary phosphate intake may contribute to differences in the presentation of CVD and bone disease. However, these differences are not adequately captured by clinically measured analytes. For a study, researchers sought to assess sex differences in acute phosphate homeostasis in response to a single oral phosphate challenge.
A total of 78 participants aged 40-76 years with a measured glomerular filtration rate greater than 60 mL/min/1.73 m² and no clinically diagnosed CVD were included. Additionally, 14 young healthy adults were included for comparison. The study aimed to examine the hormonal response, circulating mineral levels, and urinary excretion following an oral phosphate challenge to elucidate subtle alterations in phosphate homeostasis.
Both males and females exhibited similar changes in circulating phosphate, calcium, and parathyroid hormone in response to the challenge. However, females excreted approximately 1.9 times more phosphate and 2.7 times more calcium than males, despite not consuming calcium. These sex differences were also observed in healthy young adults. The increased excretion of phosphate in females did not correlate with age, serum phosphate levels, or estradiol levels. Furthermore, females with higher phosphate excretion had higher levels of bone resorption markers compared to formation markers.
The findings suggested that there are sex differences in acute phosphate homeostasis. Females appear to mobilize and excrete endogenous sources of calcium and phosphate in response to oral phosphate challenges compared to males. While high dietary phosphate levels have a negative impact on bone, the results indicated that females may be at a higher risk from these diets due to their physiological response to phosphate intake.
Source: academic.oup.com/jcem/article-abstract/108/4/909/6765272?redirectedFrom=fulltext