How Rosemary Oil Can Boost Your Hair Growth: The Natural Solution.
Essential oils are popular natural products used for many purposes, especially in skincare and haircare. Hair loss is a common issue where hair falls out from the scalp or other areas of the body. Interestingly, about 60–80% of people in developing countries rely on natural and alternative medicines to address issues like hair loss.
Essential oils, like rosemary oil, are well-known for their natural, non-toxic, and environmentally friendly qualities. They offer a range of benefits with minimal risk of side effects. Rosemary oil, in particular, has gained a reputation as a successful solution for promoting hair growth. But is this really true? Is rosemary oil backed by science, or is it just a popular belief?
In this article, I’m going to debunk the common myth about rosemary oil and its supposed hair growth properties. So, let’s dive into the facts and reach a logical conclusion on why rosemary oil doesn’t work as claimed—and what alternatives you can use that actually deliver results.
Let’s start with a basic fact: why won’t any oil really work for your hair? It’s actually quite simple. Each hair follicle is connected to a sebaceous gland, which produces an oily substance called sebum. In a healthy body, sebum’s job is to protect the hair that grows out from the follicle. The hair above the skin is already dead and has no natural protection, so nature created sebum to act as a protective layer for both your hair and skin.
This natural oil is meant to keep hair safe and healthy, but adding more oil on top doesn’t change what’s already happening at the root.
Meanwhile, the hair bulb and the portion of the hair below the sebaceous gland are alive and constantly undergoing a complex process of cell turnover. The hair follicle requires a significant amount of energy to produce new hair cells and maintain healthy growth. However, anything applied to the surface of the scalp—such as oils—cannot penetrate deep enough to reach this active area due to the natural barrier created by sebum (the body’s natural oil) and the layer of dead skin cells on the scalp.
Within the hair follicle, the hair is encased in the outer root sheath, which is surrounded by a watery environment. Since oil and water don’t mix, it’s physically impossible for oil to penetrate through this layer to reach the hair follicle or the hair itself. No matter how much oil you apply, it will remain on the surface of the scalp, unable to influence the hair's growth at the root level where it truly matters.
For oil to actually penetrate the watery environment surrounding the hair in the follicle, you’d need to somehow mix the oil with the water. Imagine having to use a blender to mix the water inside each hair follicle with the rosemary oil you apply—that’s clearly not possible! Evolution hasn’t given us a natural "mixer" for this. So, no matter how much rosemary oil you apply, it just sits on the surface, unable to reach the hair follicle where it would need to go to make any real difference.
This is why oils, including rosemary oil, can't effectively target hair growth at the root level.
You might be thinking, "But what if I apply rosemary oil to my scalp and its active ingredients slowly penetrate through the sebum and dead skin to reach the hair follicle?" Well, maybe that’s happening, but I haven’t come across any research that proves it. To confirm this, you'd need large-scale studies conducted over a long period, including scalp biopsies, to see if the active ingredients from rosemary oil are actually making their way into the hair follicle and make any change.
So far, there’s no concrete scientific evidence or techniques that can measure if rosemary oil penetrates this deeply into the scalp. Without such research, it’s hard to claim that rosemary oil truly promotes hair growth by reaching the follicle.
For now, it's safe to say that the idea of essential oils, including rosemary oil, working their way into hair follicles is more speculation than fact.
As I mentioned earlier, rosemary oil faces a tough challenge in trying to penetrate the scalp. It has to make its way through layers of sebum, the sebaceous gland, dead skin cells, and the thick, crystallized layer that sits on top of the scalp. In short, it’s highly unlikely that rosemary oil can reach the hair follicle where it would need to work.
So, to put it simply—good luck with that! While it sounds appealing, the reality is that these barriers make it nearly impossible for the oil to be truly effective in promoting hair growth.
Based on the most popular research
Let’s look at one of the most popular studies on rosemary oil for hair growth. In the abstract, it states that both groups—those using rosemary oil and those using minoxidil 2%—experienced a significant increase in hair count after 6 months. Sounds amazing, right? Well, not necessarily, and here’s why.
In this study, they compared rosemary oil to minoxidil 2%, but here's the catch: 2% minoxidil is considered too weak to show significant results in treating hair loss. Most specialists won’t recommend minoxidil 2% if you want to see real improvements. So, the study essentially compared two ingredients that are unlikely to deliver strong results, and then claimed a "significant" improvement in hair growth. The real test would be comparing rosemary oil to minoxidil 5%, which is the standard concentration known to actually produce visible results.
Another important issue with this study, which is only mentioned briefly in the abstract, is the timeframe. Hair growth studies need to be conducted over at least two years. Why? Because of the different phases of the hair growth cycle. Officially, we have three main phases: anagen (growth), catagen (transition), and telogen (resting), but experts also recognize a fifth "reserved" phase. Everyone’s hair cycle is different, and 6 months is simply too short to measure anything meaningful.
For instance, the telogen phase (when hair is essentially "dead" but still in the follicle) can last up to 4 months. If you’re applying a hair growth product during this phase, the product can’t affect those hairs because they’re no longer growing. Essentially, using a stimulating product on hair in the tellogen phase doesn’t make sense—it’s like watering a dead plant.
Fake numbers or just mistake ?
That’s not all. There are quite a few other mistakes in this research, starting with simple errors in numbers. For example, the average age of participants should be reported as 24.08, but the study lists it as 24.03—a small but unnecessary mistake. Then, when highlighting the stage of baldness, the study claims it’s 21%, but if you calculate correctly (16 and 13 out of 100), the percentage is actually 29%. These kinds of mistakes make the research look sloppy, and it doesn’t inspire confidence.
Depression scale to mesure hair loss?
But the biggest issue? The researchers used the Hamilton Rating Scale for Depression instead of the Hamilton-Norwood Scale, which is specifically designed to measure hair loss. While depression and hair loss might be linked in some cases, it’s completely unprofessional to measure hair loss with a scale meant for diagnosing depression. This kind of oversight calls the whole study into question and suggests a lack of proper attention to detail. These errors make it hard to trust the results or take them seriously.
One critical point that many studies fail to predict, but that I notice as a practitioner and trichologist, is when people typically reach for rosemary oil. Most of the time, they turn to it when they experience sudden hair loss due to seasonal shedding or telogen effluvium (TE) triggered by factors like stress, deficiencies, or hormonal changes. Seasonal hair loss, which may be a leftover from evolution, usually resolves on its own. Similarly, in cases of telogen effluvium, the body often adapts, and the hair loss stops naturally over time.
Many of my clients claim that rosemary oil helped their hair grow back during these periods, but I always tell them, “I don’t think so.” The same applies when I give a product to stop hair loss—it may appear to work, but only temporarily. The real issue remains until we identify the underlying cause of the hair loss. Without finding and addressing that cause, no oil or product can provide a long-term solution.
Chronic telogen effluvium is a more advanced condition, and even treatments like minoxidil might not be enough. Hair loss treatments are most effective when targeted at the root cause—not just the symptoms.
Lastly, let’s talk about the visual evidence. When you look at before-and-after photos from these studies, do you see a significant difference? To me, the results aren’t impressive at all. But I’ll leave that decision to you.
What to Use Instead of Rosemary Oil for Hair Loss
First of all, remember that the condition of your scalp is essential for creating a healthy environment for hair growth. Think of your scalp like fertile soil—how well you care for it will determine the quality of the "harvest." If you nourish and maintain it properly, you'll set the stage for healthy hair to grow. But if you neglect it by using random drugstore shampoos, not nourishing your body with balanced nutrition, and skipping scalp care like exfoliation, don’t expect your hair to grow well—it's simply not possible.
Now, let me teach you something important.
There are two main types of products for hair loss: the first group focuses on preventing and stopping hair loss, while the second group stimulates new hair growth.
For serious hair loss, you should reach for hair loss prevention products. For example:
- DX2 Dixidox Treatment Lotion
- DNA Pollen Treatment Hair and Scalp Lotion
Use these treatments alternately with a prevention shampoo, such as Prevention Hair Loss Shampoo.
For stimulating hair growth, there are products designed to help in specific cases, such as after chemotherapy or alopecia areata. Some excellent options for stimulating hair growth include:
- Royal Jelly Hair Loss Treatment
- Hair Nutrient Royal Jelly Shampoo
- ATP Shampoo
Another powerful option for stimulating blood circulation to the scalp is Capillary Cellular Therapy Treatment. This can enhance the health of your scalp and create the perfect environment for new hair to grow.
With the right products and proper scalp care, you can promote healthy hair growth and effectively manage hair loss.
*If you suffer from any scalp condition like seborrheic dermatitis, excessive sebum production, psoriasis, or dandruff, there are specific treatment protocols designed for these conditions.
My conclusions
So before jumping to conclusions about rosemary oil and its effectiveness for hair growth, it’s important to recognise the limitations and flaws in the research being presented.
In short, this study doesn’t offer convincing evidence that rosemary oil truly works for hair growth, and the methods used leave a lot of questions. We need more comprehensive, longer-term studies to draw any real conclusions.
In summary, while rosemary oil and other treatments may appear to help in some cases, it's often more about timing and natural recovery than the actual effectiveness of the product. True, lasting solutions come from identifying the root cause of hair loss, not relying on short-term fixes.
Special Thanks
I would like to extend my sincere gratitude to Liam Byrne, Trichologist from Navan. Liam has been my mentor in trichology, with over 40 years of experience as a trichologist and hairdresser, and he runs his own business, Robert Byrne Hairdressing, in Navan.
Thanks to Liam, I am writing this article with a clearer understanding of the misconceptions he often encounters in his practice. Many patients are advised to use products that aren't necessarily backed by science or recommended by properly qualified trichologists.
Liam, it was a pleasure to work with you, and I truly appreciate your guidance and expertise.