Prebiotic and probiotic combination improves iron absorption in female athletes in new study

August 15, 2018

A prebiotic and probiotic supplement called Regular Girl may help female athletes better absorb iron, according to a new study. 

A prebiotic and probiotic supplement called Regular Girl may help female athletes better absorb iron, according to a new study. The randomized, double-blind, placebo-controlled trial found that the synbiotic supplement combining 5 g of Sunfiber guar fiber and 8 billion CFU of Bifidobacterium lactis bacteria, when taken with 140 mg of ferrous sulfate, an iron supplement, significantly improved serum ferritin in female athletes. The trial was conducted by Marywood University and the results were presented at the American Society for Nutrition’s annual conference in June. According to makers of Regular Girl, an abstract of the study awaits publication in Current Developments in Nutrition.

Twenty female athletes with confirmed iron deficiency were eligible to participate and 19 completed the eight-week trial. Results showed that compared to the placebo group, which received the iron supplement plus placebo, the uptake of ferrous sulfate was significantly improved at four weeks and were sustained over the eight-week trial period in Regular Girl subjects, who were given the iron supplement plus the Regular Girl supplement. After controlling for baseline, regression analysis determined the serum ferritin was improved by 41% in four weeks and by more than 100% at eight weeks for the Regular Girl group, compared to 0% and 10% at four and eight weeks, respectively, for the placebo group.

These results are important because iron deficiency affects about 30% of female athletes, with major consequences to their performance. Poor iron uptake remains a major factor. While the sample size was small, these results show promise for the use of synbiotic supplements in combination with iron supplements to improve iron levels in deficient individuals, the researchers say. The researchers also stated that it’s conceivable that the use of synbiotic supplements may improve the absorption of non-heme iron from plants, which is poorly bioavailable compared to the heme iron obtained by eating meat. This could have positive implications for those who follow a plant-based diet as well as for the larger population because plant sources of iron are more commonly consumed compared to animal products.