Rosemary oil is the most over-claimed ingredient in haircare right now. It's also one of the few botanicals with a genuine human trial behind it.

Both things are true, which makes it worth pulling apart properly.

The study everyone is referring to

There's one trial doing most of the work in every rosemary claim you've seen.

Researchers ran a six-month randomized comparative trial in around 100 people with androgenetic alopecia — pattern hair loss. One group used rosemary oil. The other used 2% minoxidil, the standard over-the-counter treatment.

At six months, hair count improvements were similar between the two groups. Scalp itching was reported more often in the minoxidil group.

That's a real result and a genuinely interesting one. A botanical holding its own against a pharmaceutical is not common.

Now the parts that get left out

It was compared to 2%, not 5%. Most minoxidil sold today is 5%. The trial used the lower-strength version.

Six months is the timeline. Not six weeks. Every marketing claim built on this study is describing a half-year commitment, whether or not it says so.

It's one trial. One well-conducted study is meaningful. It is not the same as a body of replicated evidence, and anyone telling you rosemary is "clinically proven" is overstating what a single trial establishes.

The participants had a specific condition. The study looked at androgenetic alopecia. It doesn't tell us much about postpartum shedding, stress-related shedding, or breakage — which are different problems with different mechanisms.

Massage was part of it. A separate study on an essential-oil blend for alopecia areata found the aromatic blend outperformed carrier oil alone — but both groups massaged. Scalp massage is doing some of the work in any topical oil protocol, and it's difficult to fully separate the two.

So does it work?

My honest read, as someone who formulates with it: rosemary is one of the better-evidenced botanicals available, and that's a low bar that most ingredients don't clear.

It is not minoxidil. It is not a treatment. If you have significant pattern hair loss and you want the strongest available option, that conversation belongs with a dermatologist, not with me.

What rosemary is: a reasonable, well-tolerated ingredient with real human data, worth including in a routine you'll actually keep up for six months.

How to use it sensibly

• Never neat on the scalp. Rosemary essential oil is potent and can irritate. It belongs diluted in a carrier oil — which is how it's used in any properly formulated product.
• Scalp, not lengths. The follicle is what you're trying to reach.
• Two to three times a week. More often isn't better.
• Patch test first, especially if you have sensitive skin.
• Give it six months before you decide anything, because that's what the study did.

Why it's in Motiya — and why it isn't alone

Rosemary is in every Motiya product. But I don't build a formula on a single ingredient, because no single ingredient carries that much weight.

In the Hair Repair Oil it sits alongside pumpkin seed oil, which has its own randomized trial data, and rice bran extract, which has human trial support for density and diameter. Different ingredients, different mechanisms, layered.

You can read the full evidence breakdown for all thirteen herbs — including which ones only have animal or lab data — on our Science page. We label the evidence tier for every single one, because "there's a study" and "there's a human randomized trial" are very different claims.

Motiya products are cosmetics, not drugs. We don't claim to treat or cure medical hair-loss conditions. For medical hair loss, please consult a clinician.