Ferrous Fumarate vs. Ferrous Sulfate
Among 1,931 on-market iron products with an identifiable primary form, 60.8% use Ferrous Fumarate (1,174 products) and 8.2% use Ferrous Sulfate (159).
| Ferrous Fumarate | Ferrous Sulfate | |
|---|---|---|
| Quality tier | Unrated | Tier 2 |
| Iron by weight | 32.9% | 20.1% |
| Share of market | 60.8% | 8.2% |
| On-market products | 1,174 | 159 |
| Median declared dose | 18 elemental mg middle half: 8–26 | 18 elemental mg middle half: 11.5–65 |
| Most common brands | DC, Wonder Laboratories, GNC Women's Ultra Mega | Geri-Care, Rugby, Major |
Doses are declared per serving in elemental mg. “By weight” is the share of the ingredient that is the nutrient itself (e.g. elemental magnesium in a magnesium salt).
Why Ferrous Fumarate is unrated
Widely marketed as comparably bioavailable to ferrous sulfate with less GI upset, but no comparative human absorption study was independently verified.
Source: uncertain -- needs review
Why Ferrous Sulfate is tier 2
Reference-standard iron salt used as the comparator in most bioavailability literature; showed lower apparent bioavailability (26.7%) than bisglycinate chelate (90.9%) in one head-to-head pediatric trial.
Source: Pineda O, Ashmead HD. 2001, PMID 11377130
Other iron comparisons
- Ferrous Fumarate vs. Ferrous/Iron Bisglycinate Chelate
- Ferrous Fumarate vs. Iron Amino Acid Chelate
- Ferrous Fumarate vs. Ferrous Gluconate
- Ferrous/Iron Bisglycinate Chelate vs. Iron Amino Acid Chelate
- Ferrous/Iron Bisglycinate Chelate vs. Ferrous Sulfate
- Ferrous/Iron Bisglycinate Chelate vs. Ferrous Gluconate
- Iron Amino Acid Chelate vs. Ferrous Sulfate
- Iron Amino Acid Chelate vs. Ferrous Gluconate
- Ferrous Sulfate vs. Ferrous Gluconate