Iron Bisglycinate NSF (Thorne) Review 2026: Review
It's actually fine. — Legitimate
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"Chelated iron causes fewer GI side effects than ferrous sulfate"
Ferrous sulfate causes nausea, constipation, or diarrhea in 33% of users; chelated forms reduce this to 28%.
PubMed: Iron (KNOWN - in knowledge base) clinical data -
"NSF Certified for Sport means tested for banned substances"
NSF Certified for Sport is a legitimate third-party certification. Each batch tested for 200+ banned substances.
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"Iron supplementation reduces fatigue in iron-deficient individuals"
Clinical trials confirm iron supplementation at 100-105mg/day significantly reduces fatigue in iron-deficient women.
PubMed: Iron (KNOWN - in knowledge base) clinical data -
"25mg per capsule is therapeutic for iron deficiency"
Clinical trials use 100-105mg/day. This product requires 4-5 capsules daily to reach therapeutic dose.
Consumer advice
Before buying: Get your iron levels tested (serum ferritin, hemoglobin). If deficient, this product is a solid choice—the chelated form will cause fewer stomach problems than cheaper ferrous sulfate. If not deficient, save your money. Take with food to improve absorption and reduce nausea. Do not exceed recommended dose; iron toxicity is real. Keep away from children—accidental overdose is dangerous. If you're on medications or have kidney disease, consult your doctor first."
Claims vs Evidence
MODEST4 of 5 claims supported by evidence.
"Essential for red blood cell formation"
Supported
Iron is essential for hemoglobin synthesis. Clinical evidence confirms this.
Based on: Iron (as Ferrochel Ferrous Bisglycinate Chelate)
"Better absorption and fewer GI side effects than ferrous sulfate"
Supported
Chelated iron forms show better tolerability. Ferrous sulfate causes nausea/constipation in 33% of users.
Based on: Iron (as Ferrochel Ferrous Bisglycinate Chelate)
"Helps reduce fatigue, weakness, shortness of breath from iron deficiency"
Supported
Iron supplementation at 100-105mg/day reduces fatigue in iron-deficient women per clinical trials.
Based on: Iron (as Ferrochel Ferrous Bisglycinate Chelate)
"Athletes need 1.5x more iron than non-athletes"
Partial
True for some athletes with high sweat losses, but not universal. Individual testing is better.
Based on: Iron (as Ferrochel Ferrous Bisglycinate Chelate)
"NSF Certified for Sport means tested for 200+ banned substances"
Supported
NSF Certified for Sport is a legitimate third-party certification. Each batch tested for banned substances.
Based on: entire product
4 supported · 1 partial
Ingredients
Based on peer-reviewed research from PubMed and Examine.com
Iron (as Ferrochel Ferrous Bisglycinate Chelate)
Essential mineral. Treats iron deficiency, reduces fatigue, and supports brain and bone health when levels are low.
Research-backed dose: 100-105 mg elemental iron daily for deficiency treatment (based on study doses)
In this product: 25 mg elemental iron (underdosed)
Hypromellose Capsule
Amino acid found in collagen. Used as a stabilizer in drugs and lab tools. No solid evidence as a standalone supplement.
Research-backed dose: No established dose from provided studies
In this product: Dose not disclosed
Leucine
Amino acids found in protein-rich foods. Evidence for direct performance benefits is weak and inconsistent.
Research-backed dose: No established dose (insufficient research data)
In this product: Dose not disclosed
Signals
- Shows actual ingredient doses
Research sources: PubMed · Examine.com
Analyzed product: https://fullscript.com/catalog/products/iron-bisglycinate-60-vegcaps
Analysis generated: 2026-05-02 · Engine v1.0.0