Other actives
Royal jelly
Also listed as royal jelly extract, bee milk
A bee secretion marketed for hair growth and nourishment. There is no human evidence, and the one direct mouse study found it made hair thinner.
What it is
Royal jelly is the protein-rich secretion worker bees feed to queen larvae. Its 'queen bee' image drives claims that it nourishes hair and skin. In a 2025 study that tested it directly on hair growth, royal jelly applied to mouse skin produced thinner hair shafts and slowed hair follicle stem cells.
How strong is the evidence?
No real evidenceNo human trials support hair or skin benefits of topical royal jelly. The direct animal evidence (mice, 2025) points toward thinner hair, the opposite of the claim.
What it's used for, checked
Promotes hair growth
UnprovenNo human trials; a mouse study found thinner hair shafts.
Nourishes or conditions hair
UnprovenAny feel comes from the rest of the formula.
Who should be careful
- Royal jelly can cause serious allergic reactions, including asthma attacks and anaphylaxis, mostly when swallowed; people with asthma, eczema or allergies to bees or pollen should avoid it.
- Stop topical use if the scalp or skin becomes red, itchy or swollen.
The studies
Every citation is checked against its PubMed record.
- Royal Jelly Induces Thin Hair Shaft Formation by Suppressing Proliferation of Hair Follicle Stem Cells in Mice. Hamanishi T, Koga H, Nishimura T, Kobayashi K · ACS Omega · 2025 · Animal and cell study
Royal jelly applied to mouse skin produced thinner hair shafts and smaller hair bulbs, and suppressed hair follicle stem cell growth in mice and in culture: the opposite of the hair-growth claim.