Black soybean and beer yeast
Two 20% inclusions anchoring the density line. Substantial levels, traditional use, and a modest evidence base.
Black soybean
Glycine max with anthocyanin-rich black seed coats. It contains isoflavones — genistein and daidzein — which are phytoestrogens with weak oestrogen-receptor activity, plus anthocyanins as antioxidants. The hair and scalp rationale rests on two threads: isoflavone activity relevant to androgen-driven follicle miniaturisation, and antioxidant protection of the follicular environment.
It appears at 20% across the Vegalab NanoDensity Ampoule, Shampoo and Tonic. That is a substantial inclusion, and unusually for this range the level is not the weak point of the claim — the evidence base is.
Beer yeast
Saccharomyces-derived, at 20% in the same three products. Yeast provides B vitamins, beta-glucans, peptides and nucleotides. Brewer's yeast has a long history in hair and skin preparations, and beta-glucan's barrier and soothing activity is reasonably supported. Specific evidence for beer yeast improving hair density is limited.
How to present this honestly
Both ingredients are present at levels that could plausibly matter, which is more than can be said for several ingredients elsewhere in these ranges. Both have mechanistic rationales that are coherent rather than fanciful. Neither has clinical evidence for hair density that would survive scrutiny.
The accurate framing is a traditionally used, generously included botanical and yeast system with plausible mechanisms and limited clinical data — which is a perfectly respectable thing to say, and considerably more durable than a growth claim.
What does black soybean and beer yeast not do?
Neither is a treatment for androgenetic alopecia, and neither should be positioned against products with clinical evidence for that indication. Phytoestrogen content also means anyone with a hormone-sensitive condition may reasonably want to raise topical use with a clinician.