Johnen J., Waizenegger J., Ellinger J., Lütjohann D., Steffens K.E., Wagner K.G., Stoffel-Wagner B., Dolscheid-Pommerich R., Ellinger S. Effects of regular consumption of a β-glucan-rich oyster mushroom powder on cholesterol metabolism in adults with moderately elevated LDL-cholesterol concentrations: a double-blind randomized controlled trial. Nutrition & Metabolism. 2026;23:53.
Rationale
Oat and barley β-glucans carry an approved cholesterol claim; mushroom β-glucans differ structurally, and whether the same effect holds needed a direct test in people with elevated LDL.
Methods
A double-blind placebo-controlled parallel RCT: 46 adults with LDL-C 116–190 mg/dL drank a daily beverage containing 8.4 g oyster-mushroom powder (3 g β-glucans) or a mushroom-free control for 4 weeks. Lipids, apolipoproteins, cholesterol-absorption and synthesis markers, and gene expression were measured; serum ergosterol verified intake.
Results
The primary endpoint LDL-C did not change significantly; nor did other lipids, apolipoproteins or expression of cholesterol-metabolism genes. A post-hoc sex-adjusted analysis found reduced cholesterol-absorption markers — stronger in women. Ergosterol in serum confirmed participants actually took the powder.
Conclusions
A clean null on the primary endpoint: mushroom β-glucan at this dose does not lower LDL in 4 weeks — with a secondary hint that cholesterol absorption is being pushed down, which may need longer or different dosing to surface in LDL itself.
Worth noting
The compliance marker (serum ergosterol) is a methodological nicety rarely seen — the null result is trustworthy because intake is proven. Honest reading: mushroom β-glucans ≠ oat β-glucans in structure or effect; the absorption-marker signal keeps a mechanism alive but does not rescue the primary outcome.