Chelated iron, such as the iron bisglycinate in MAS Iron, is iron bound to two molecules of the amino acid glycine.
This form improves absorption because the two molecules of glycine block dietary factors like fiber from interfering with absorption.
The bisglycinate form is also more soluble, which translates to better absorption, which in turn decreases gastrointestinal side effects like constipation and stomach upset.
What does the science say about iron bisglycinate?
- A study in 100 anemic patients compared 120mg iron sulfate to 120mg, 60mg, and 30mg doses of iron bisglycinate daily for one month.
- 60mg iron bisglycinate for four weeks provided the best dose response in terms of elevating hemoglobin and serum ferritin (a protein that enhanced iron storage).
- The 120mg dose of iron bisglycinate resulted in 50% fewer GI side effects compared to the same dose of iron sulfate.
- A randomized, crossover study of the tolerability of iron bisglycinate versus iron sulfate found significantly more subjects preferred the bisglycinate form because it was less likely to cause GI upset.
“Ferrous Sulfate Oral : Uses, Side Effects, Interactions, Pictures, Warnings & Dosing.” WebMD.
“Iron Deficiency Treatment for Chronic Fatigue Symptoms.” University Health News, 5 Mar. 2019.
Duque, X., Martinez, H., Vilchis-Gil, J. et al. Effect of supplementation with ferrous sulfate or iron bis-glycinate chelate on ferritin concentration in Mexican schoolchildren: a randomized controlled trial. Nutr J 13, 71 (2014).
Bumrungpert A, Pavadhgul P, Piromsawasdi T, Mozafari MR. Efficacy and Safety of Ferrous Bisglycinate and Folinic Acid in the Control of Iron Deficiency in Pregnant Women: A Randomized, Controlled Trial. Nutrients. 2022 Jan 20;14(3):452.
Milman N, Jønsson L, Dyre P, Pedersen PL, Larsen LG. Ferrous bisglycinate 25 mg iron is as effective as ferrous sulfate 50 mg iron in the prophylaxis of iron deficiency and anemia during pregnancy in a randomized trial. J Perinat Med. 2014 Mar;42(2):197-206.
Linda
Great customer service
Liking the product so far and very happy with the customer service. I had a few questions about using iron given a few of my issues and their support team got back to me right away.
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Carrie
Wow
I bought this product as soon as it launched. Honestly, it almost seemed like they developed the product for my exact issues. I’ve had issues with low iron since I was in college and I tried everything to keep my levels consistently up, even cooking in cast iron pans. I wanted to try this product to see if it was really gentler on my stomach. So far no issues and after only a few weeks I already feel like I do when I know my iron levels are up. I’ll get some blood work soon, but really impressed with the product so far!
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Martin
Five stars
It works as advertised and has supercharged my workout progress. Five stars from me.
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Dan
Skeptical but glad I did
I was skeptical at first since I may have been one of the first to purchase during their initial launch, but I am happy I did.Order arrived quick with solid packaging. Nice touch. I haven’t been able to test with any labs yet (still too soon) but I have noticed a lot less lethargy throughout the day and I’ve felt a lot better during my workouts the last few weeks.
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Tom
Finally
I have tried other iron supplements in the past, but they always left me feeling bloated and uncomfortable. I didn’t experience any of those unpleasant side effects. Plus, knowing that it is well-absorbed means I can trust that my body is getting the iron it needs.
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Melissa
Effective but wish it was a gummy
I’ve been using a gummy iron for quite a while and I really prefer that than taking pills. The pills are small, but I still don’t like taking them. I may purchase the ferritin test to see how much different it is.
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