Soluble fiber plus probiotics found to improve iron uptake in female athletes

Soluble fiber plus probiotics found to improve iron uptake in female athletes

25 Jul 2018 --- Combining an OTC dosage of iron combined with the product Regular Girl, a premium blend of soluble fiber plus probiotics, may significantly improve iron uptake with no known side effects, a new Marywood University study has shown. Iron deficiency affects approximately 30 percent of female athletes.

Regular Girl is a synbiotic blend of prebiotic fiber (Sunfiber, a highly stable guar fiber) and clinically proven B. lactis probiotics. Regular Girl is all-natural and 100 percent gluten-free. It contains no eggs, yeast, soy, sugar, salt, artificial flavors or preservatives. It is also certified low-FODMAP and Non-GMO Project Verified. For the eight-week randomized, double-blind, placebo-controlled study, 20 recreational-level female athletes – all of whom were confirmed to be iron deficient – were divided into two groups. One group received Regular Girl (6 g guar fiber and probiotics) and 140 mg of ferrous sulfate, while the placebo group received 140 mg ferrous sulfate and a placebo. 
Click to EnlargeAfter four weeks, the Regular Girl group’s blood serum ferritin, a marker for iron status, had increased by 41 percent, while the placebo group showed no response. At the end of eight weeks, the Regular Girl group’s serum ferritin had almost doubled, the study found. 

“I have previously studied iron’s effects on active women’s performance. My goal with this study was to look at how we can maximize iron uptake,” says Dianne DellaValle, Ph.D., RDN, LDN, a Marywood University Associate Professor and Research Dietitian. “When I learned about the pre- and probiotics in Regular Girl, I knew they were good for uptake of certain minerals. I wanted to see if this simple intervention would benefit female athletes.” 

“This was an amazing response to a low-dose iron supplement,” DellaValle comments. “The exciting thing about this study, even though this was a small sample and we didn’t use elite athletes, is that it demonstrated there are simple ways to improve our uptake of even small amounts of iron.” 
There are two different types of dietary iron: heme and non-heme. Non-heme iron is found in plant foods (e.g., beans, cereals and vegetables), and is the more poorly absorbed of the two. The richest dietary iron source is heme iron found in animal tissue such as meats, which is well absorbed by the body. 
“While this was a smaller sample, if synbiotic supplementation can enhance the iron uptake in iron-deficient female athletes during repletion of iron status, it could conceivably improve the iron bioavailability of non-heme iron sources and mixed meals (e.g. heme + non-heme iron sources),” DellaValle adds. “Non-heme iron is the most abundant source of dietary iron worldwide, so using a synbiotic supplement could aid in ameliorating iron deficiency in women around the globe.”
Based on this study, DellaValle concludes that it may also be beneficial for female athletes to receive dietary counseling on pre- and probiotic food choices, and/or synbiotic supplementation to maximize iron bioavailability.
As a brand, Regular Girl seeks to tap into the growing women’s digestive health market, with a “tongue in cheek” approach.

“Roughly four years ago as the probiotic market was demonstrating steady growth, we reviewed the supplemental fiber market and opportunities in the prebiotic market and discovered some white space,” Mike Danielson, Marketing Representative for Regular Girl, tells NutritionInsight. “It was clear to us that women were making more of the fiber purchases, as with dietary supplements, and women talked about their digestive health issues among themselves more often and more comfortably than men.”
“This lead us to the idea of a gender-specific pre- and probiotic product. These insights also presented the idea of taking a fun tongue and cheek approach to an uncomfortable topic, while at the same time explaining the differences between soluble and insoluble fibers and the relationship between soluble prebiotic fibers, like Sunfiber, and probiotics,” he says.
According to Danielson, Regular Girl looks forward to continue supporting research for female health, focusing on nutrition and improving the health of the gut and the brain. The brand will shortly launch two new products:  

  • Regular Girl Wellness – focusing on both gut and urinary health.
  • Regular Girl Indulgence – prebiotic fiber in probiotic chocolates.

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