Psyllium Fiber Market Report: Sales Volume, Market Share, Leading Brands & Market Trends

Metamucil is the best-performing psyllium fiber brand in July 2026, moving 210,000 units across 5 ASINs for 67.7% of Top 10 volume. NOW Foods follows with 60,000 units (19.4%), ahead of NOW on 40,000 units (12.9%).

With 3 brands splitting the Top 10 and 100.0% 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 $11.38 to $26.84, 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. Specifically, 2 ASINs forced its way in: B000N7DP6G booked 20K units at $11.76, with ▲ 1900.0% MoM change. On the growth side, B0B92CPGJ9 leads positive momentum with ▲ 200.0% MoM growth on 3K 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already changed hands — an incumbent gave up its place to make room, so any competitive set drawn up a month ago is now out of date.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.