Context
Soy isoflavones are primarily found in soybeans and soy-based products (such as tofu, tempeh, soy milk, soy yogurt, and soy-based meat substitutes). At appropriate doses, soy isoflavones exhibit both estrogenic and anti-thyroid effects in animals and humans. The outcome, whether advantageous or detrimental, depends on the individual’s physiological condition. Systemic lupus erythematosus (SLE) is an autoimmune disease primarily affecting humans, with 90% of subjects being female. Genetic factors on the X chromosome and estrogen exposure are believed to contribute to SLE occurrence. The role of environmental factors, such as estrogens and phytoestrogens from soy, in SLE is still under debate.
Hence, selecting an appropriate biomarker is of utmost importance in accurately assessing exposure to soy isoflavones and determining their impact on human health. Previous studies have primarily focused on establishing correlations between dietary intake and isoflavone concentrations in urine, serum, and plasma samples, serving as biomarkers of exposure. However, in order to enhance our understanding of human exposure, the concept of developing an assay using hair samples has emerged. Hair is considered a more suitable candidate, as it helps smooth out variations in daily isoflavone intake and biological fluid concentrations. The present study aims to explore the measurement of soy isoflavones in hair as a potential biomarker of exposure, which could provide novel insights for analyzing the health effects of isoflavones.
