Quinoa as Functional Food? Urinary elimination of ecdysterone after consumption of quinoa alone and in combination with spinach

Abstract

The phytosteroid ecdysterone is included on the monitoring list of the World Anti-Doping Agency. Therefore, the consumption of food rich in ecdysterone is the focus of a lively debate. Thus, urinary excretion of ecdysterone and its metabolites in humans was investigated following quinoa consumption alone and in combination with spinach. After intake of both preparations, ecdysterone and two metabolites were excreted in urine. Maximum concentrations of ecdysterone ranged from 0.44-5.50{micro}g/mL after quinoa and 0.34- 4.09{micro}g/mL after quinoa with spinach. The total urinary excreted amount as parent drug plus metabolites was 2.60(1.09)% following quinoa and 1.71(0.86)% after combination. Significant differences were found in total urinary excreted amounts of ecdysterone, 14-deoxy-ecdysterone, and 14-deoxy-poststerone. In conclusion, only small proportions of ecdysterone from quinoa and the combination with spinach were excreted in urine. The results indicate that both, quinoa and spinach, are poor sources of ecdysterone.