Iron Supplement Market Report: Sales Volume, Market Share, Leading Brands & Market Trends

THORNE is the best-performing iron supplement brand in July 2026, moving 70,000 units across 2 ASINs for 33.3% of Top 10 volume. Nature Made follows with 50,000 units (23.8%), ahead of Nature's Bounty on 30,000 units (14.3%).

With 8 brands splitting the Top 10 and 71.4% of volume sitting with three of them, this is a concentrated shelf — the leaders hold multiple listings or one very high-velocity ASIN, so a new entrant competes against established review moats rather than an open field. Average selling prices among the leaders run from $5.20 to $21.00, which frames the price band a competing listing has to justify.

Based on July 2026 data, this shortlist surfaces the two kinds of ASIN worth keeping an eye on — the ones that just broke into the Top 10, and the ones growing fastest month over month. On the growth side, B076DJSPSQ leads positive momentum with ▲ 33.3% MoM growth on 4K units, with B0797GZDZL close behind at ▲ 25.0% MoM on 50K units.

The two signals carry different weight. A fresh entrant means share has already changed hands — an incumbent gave up its place to make room, so any competitive set drawn up a month ago is now out of date. A steep growth rate works as the earlier warning: it marks demand that is still compounding, usually a month or two before the ranking catches up to it.