Best Iron
2026
THORNE Iron Bisglycinate 25 mg
Iron that won't upset your stomach.
Score 81/100 $16
Why this one
THORNE Iron Bisglycinate stands out for its superior absorption formula that eliminates the stomach upset plaguing traditional iron supplements. Backed by healthcare professionals, third-party certifications, and consistent user reports of sustained energy without GI distress, it delivers real results—making the premium price justified for those prioritizing tolerability and efficacy.
Pros
- ✓ Exceptional stomach tolerability - doesn't cause GI distress like other iron supplements
- ✓ Proven effectiveness - users report measurable iron level improvements within 6 weeks
- ✓ Sustained energy and athletic performance - enables users to exercise without fatigue or collapse
- ✓ Superior absorption with chelated bisglycinate form minimizes GI upset and nausea
- ✓ NSF Certified for Sport and gluten-free formula appeals to athletes and those with dietary restrictions
Cons
- ✗ Premium pricing - positioned as expensive compared to budget alternatives like Kirkland
- ✗ May be overkill for some - some users suggest half doses or targeted supplementation instead
- ✗ Premium price point compared to standard iron supplements
- ✗ Small capsule size requires multiple servings for therapeutic dosing
Our methodology
Based on AI analysis of 7,769 Amazon reviews, Reddit discussions, and expert reviews. Scored 81/100.
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