Three Arrows Iron Repair (Heme Iron) Review
#5 of 9 · Best Absorbed✓ Label verified · Supplement Facts read Sep 7, 2026Real retailer photo, cut out. Label unedited.
Consider it. The escape hatch when every other iron fails. Heme iron is genuinely the gentlest, best-absorbed option, and this one is Monash Low-FODMAP certified.
~$39.95~$0.44
Why It Scores 8.0 — And The Label Line Behind Each Number
Form & Bioavailability
30% of scoreHeme iron is absorbed via a dedicated pathway that dietary inhibitors do not block — the most bioavailable oral form. This is the review's single strongest form score.
- Form
- Heme iron (grass-fed bovine spleen concentrate)
- Diet
- Not vegetarian (bovine-gelatin caps)
Dose Appropriateness
20% of score~20 mg per capsule is a reasonable repletion dose, but that figure is total spleen-concentrate iron, not purely heme, so the effective heme dose is lower than the headline number.
GI Tolerance & Safety
20% of scoreMonash Low-FODMAP certified and frequently tolerated even when other irons fail — heme iron's absorption pathway sidesteps much of the gut irritation of non-heme forms.
Third-Party Testing & Purity
20% of scoreCarries a Monash University Low-FODMAP certification, but efficacy evidence is largely brand-generated and there is no product-level NSF/USP potency seal.
- Certification
- Monash University Low FODMAP
Value per Serving
10% of scoreAt ~$0.44 per capsule it is the priciest per milligram of iron in the set — you pay a steep premium for the heme form.
- Size
- 90 capsules (90 servings)
- Serving
- 1 capsule daily
- Price (approx.)
- ~$39.95
- Cost / serving
- ~$0.44
- More Specs
- Elemental iron
- ~20 mg per capsule
Label verified. Every figure read from the Supplement Facts photo, Sep 7, 2026.
Marketing Claims Vs. Reality
Heme iron is the best-absorbed form, not blocked by tannins, phytates or antacids
Heme iron is absorbed through a distinct, high-efficiency pathway independent of the dietary inhibitors that suppress non-heme iron — a well-established nutritional distinction (the inhibitor problem Cook & Reddy 2001 studied applies to non-heme, not heme).
Monash University Low-FODMAP certified
A recognized third-party gut-tolerance certification from Monash University — verifiable and relevant to sensitive-digestion users.
Delivers ~20 mg of heme iron per capsule
The ~20 mg figure is total iron from the spleen concentrate, not purely heme iron, so the effective heme content is lower than the headline number implies.
Often tolerated and effective when other irons fail
Plausible given heme iron's absorption mechanism and the Low-FODMAP certification, but the efficacy support is largely brand-generated rather than independent trial data.
What Our Test Actually Found
The best-absorbed form, full stop
Heme iron uses a dedicated intestinal transporter that ignores the tannins, phytates and stomach-acid dependence that hamstring non-heme iron. For someone whose meals or antacids sabotage ferrous forms, that mechanism is the whole reason to consider it.
Read the '20 mg' carefully
The label figure is total iron in the spleen concentrate, not purely heme iron. The dose is still useful, but it is not directly comparable to '25 mg elemental' on a non-heme chelate — an honest caveat the marketing glosses over.
Certified for sensitive guts
The Monash Low-FODMAP certification is a real, third-party tolerance credential. Combined with heme iron's gentler absorption, this is the pick to reach for after ferrous salts and chelates have both failed you.
You pay for the escape hatch
At ~$0.44 a capsule it is the most expensive iron here per milligram, it is bovine-derived so vegetarians are out, and the efficacy data is the brand's own. Excellent for a specific problem, poor as a general-purpose default.
Full analysis: all pros & cons (8), buy if / skip if
- Heme iron — best-absorbed form, not blocked by tannins, phytates or antacids
- Monash Low FODMAP certified for sensitive digestion
- Single-ingredient 'Simply' formula
- Often tolerated even when other irons fail
- Best-in-set form and bioavailability
- Priciest per milligram of iron in the set
- Animal-derived — not vegan or vegetarian
- Efficacy evidence is largely brand-generated; '20 mg' is total spleen-concentrate iron, not purely heme
- Ferrous salts and chelates both cause you GI distress
- You have a sensitive gut or IBS and need Low-FODMAP certification
- You take antacids or eat high-tannin/phytate meals that block non-heme iron
- You want the best-absorbed iron regardless of price
- You are vegetarian or vegan (it is bovine-derived)
- You want the best value per milligram of iron
Heme iron is genuinely the gentlest, best-absorbed option, and this one is Monash Low-FODMAP certified. But it is the priciest per milligram in the set, animal-derived, and the '~20 mg' is total spleen-concentrate iron rather than purely heme. A targeted pick, not a default.
If ferrous salts and even chelates wreck your gut, heme iron is the escape hatch. Concentrated from grass-fed bovine spleen, it is the best-absorbed form of iron and is not blocked by tannins, phytates or antacids the way non-heme iron is. You pay dearly for it, it is off the table if you are vegetarian, and the efficacy evidence is largely the brand's own.
A targeted pick for gut-sensitive users, not a default
If ferrous salts and even chelates wreck your gut, heme iron is the escape hatch — genuinely the gentlest, best-absorbed option. You pay dearly for it, it is off the table if you are vegetarian, and the evidence is mostly the brand's own. A targeted pick, not a default.
If This Doesn’t Fit — Try These
01Thorne Iron Bisglycinate
Our take: if you have confirmed low iron and want one bottle to trust, this is it.
08Vitron-C
Our take: the pick if you want a high dose with a real safety margin — carbonyl iron is the form toxicologists prefer around children.
02Nutricost Iron Bisglycinate
Our take: the smart-money buy.
Quick Answers
What makes heme iron 'best absorbed'?
It is taken up through a dedicated intestinal pathway that is not blocked by tannins, phytates or low stomach acid — the factors that suppress non-heme iron (Cook & Reddy 2001). That is why it often works when ferrous forms cause problems or absorb poorly.
Can vegetarians take it?
No. It is concentrated from grass-fed bovine spleen and uses bovine-gelatin capsules, so it is unsuitable for vegetarians and vegans. Choose a bisglycinate chelate instead.
Is it really 20 mg of iron?
The ~20 mg is total iron from the spleen concentrate, not purely heme iron, so the effective heme dose is lower. It is a real dose, just not directly comparable to '25 mg elemental' on a non-heme product.
Should this be my first iron?
Usually not. Try a gentle bisglycinate chelate first — it is cheaper and plant-based. Reserve heme iron for when ferrous salts and chelates have both caused you GI distress.
Sources & Further Reading
2 peer-reviewed sources, each linked to PubMed
- [1] Cook JD, Reddy MB. Am J Clin Nutr. 2001;73(1):93-98. PMID 11124756 — Effect of ascorbic acid intake on nonheme-iron absorption from a complete diet. Non-heme iron absorption is heavily modulated by dietary factors — precisely the inhibition that heme iron bypasses.
- [2] Kassebaum NJ, et al. Blood. 2014;123(5):615-624. PMID 24297872 — A systematic analysis of global anemia burden from 1990 to 2010. Iron-deficiency anemia is the dominant anemia worldwide, underscoring the need for well-absorbed options when standard iron fails.
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