Oils, Microneedles, And New Drugs: What Does The Latest Science Say On Hair Loss And Regrowth?

Hair loss is something that many people will experience in their lives, and though some might be tempted to say, “it’s just hair”, it can have a profoundly negative impact on the people affected by it. As a result, science has long been searching for a way that hair loss can be treated – so what’s the latest in this area of research?

Hair loss, also known as alopecia, can have a whole host of causes: genetics, hormones, age, stress, chemotherapy, and even wearing your hair in a particular way.

Losing hair can have all sorts of impacts on a person – it’s far from just a matter of aesthetics. A review from 2021 found that people with hair loss can experience anxiety, depression, and decreased confidence, alongside social withdrawal and a reduction in work. It’s no surprise, then, that people might seek out treatment in all kinds of places.

Home remedies

DIY ways to regrow hair aren’t exactly a new thing, but the rise of social media platforms has seen all sorts of home remedies pushed into the limelight. But beyond anecdotal evidence given in a 60-second video, is there any scientific research that suggests they work?

Rosemary oil

You’d be hard-pressed not to come across the “rosemary oil” side of TikTok (and the #ad in the captions) if you spend enough time doomscrolling. Lots of those videos claim that the oil has helped them regrow lost hair, but there’s currently not enough research to completely back up those claims.

A 2022 study concluded that a gel containing rosemary oil had a hair growth-enhancing effect similar to that of minoxidil (better known as Rogaine), a medication used to treat androgenetic (pattern) hair loss. But here’s the catch – the study was carried out on rats, and their fur had been removed using hair removal cream. 

Such studies help to assess the safety of a possible treatment before it’s used in humans, but equally, that means scientists can’t make any solid conclusions about rosemary oil’s efficacy in humans either. 

One widely referenced 2015 paper tested it out on humans in comparison to minoxidil and claims to have found regrowth, but the study only investigated 100 people, all of whom had androgenetic hair loss, so the results can’t justifiably be applied to all types of hair loss. 

As Dr Michelle Wong of Lab Muffin Beauty Science points out, the abstract of the 2015 study appears promising – however, there are many issues with the study as a whole. These include what appear to be typos and calculation errors, the relatively short length of the study in relation to hair growth cycles, the low percentage of minoxidil used, and a depression assessment scale being used to assess hair loss.



Something that’s also often touted to help with hair loss, sometimes alongside rosemary oil, is microneedling. Is it worth sticking a bunch of tiny needles in your scalp? Recent review studies suggest that, while there appear to be some promising results, more (and higher quality) data is needed to support its use for stimulating hair regrowth.

For example, a 2021 review found that there was limited evidence for the effectiveness of microneedling on its own; most research trials have combined it with other therapies, like minoxidil. 

Another review, also published in 2021, concluded that though there were “generally favorable results” for using microneedling to treat pattern hair loss and alopecia areata (hair loss with an autoimmune cause), a lot of the data were of low quality.

If someone is still interested in microneedling, it’s generally recommended as a point of safety to go to a dermatologist if you want to use a medical-grade device; piercing the skin without proper protocols can lead to damage or an infection.

Clinical treatments

The first US approval of hair growth treatment came back in 1988 for Rogaine, aka minoxidil, though its recommended use is for hereditary pattern hair loss. Progress towards other treatments for all types of hair loss dwindled in the following years; hair transplants have also been used successfully, but they are invasive and can be expensive. However, there’s been a recent uptick in additional therapies either being developed or approved.

The first treatment for severe alopecia areata

First approved by the UK’s Medicines and Healthcare products Regulatory Agency back in November 2023, ritlecitinib, aka Litfulo, recently became the first treatment for severe alopecia areata recommended for use on the National Health Service (NHS). It was also approved for use by the Food and Drug Administration (FDA) last year – though it wasn’t the first treatment to be approved, with baricitinib (aka Olumiant) taking that title.

The approvals came after clinical trial data showed the drug to be more effective than a placebo at improving hair regrowth, and even a continued improved response for up to two years. The treatment is taken as a daily pill and according to the National Institute for Health and Care Excellence, “works by reducing the enzymes that cause inflammation and subsequent hair loss at the follicle.”

MicroRNA could be promising

A study published last year identified a small molecule called microRNA-205 (miR-205) that appeared to promote hair regrowth in mice by “softening up” stem cells in their hair follicles. This effect was seen relatively quickly and in both young and old mice. 

However, again, it’s important to note that this study wasn’t carried out in humans. A lot more research is required to assess both efficacy and safety and gather data to the point sufficient for clinical approval.

“Because of the potential to deliver microRNA by nanoparticles directly into the skin, next we will test whether topically delivered miR-205 can stimulate hair growth first in mice,” corresponding author Rui Yi, the Paul E. Steiner Research Professor of Pathology and professor of dermatology at Northwestern University Feinberg School of Medicine, said in a statement

“If successful, we will design experiments to test whether this microRNA can promote hair growth potentially in humans.”

Cold capping

Many people who go through chemotherapy experience some degree of hair loss. Some healthcare services offer scalp cooling, often in the form of “cold capping”, to potentially reduce that loss. It doesn’t necessarily work for everyone, but a new study has identified some of the factors that could make using a cold cap more or less successful.

The study found that cold capping might be more effective than previous literature has indicated, with a 92.1 percent success rate. The authors suggest that this could be down to wearing the cold cap properly and for the prescribed amount of time, as well as completing the cold capping process.

The researchers also found that the type of chemotherapy someone was receiving may make a difference to cold capping effectiveness, whilst neither patient race, ethnicity, or hair characteristics appeared to make a difference.

However, the authors of the study acknowledge some limitations to their results. Along with having no control group, the sample of patients was small; consisted mostly of women undergoing breast cancer treatment; and participants were mostly white. As such, the findings might not be generalizable to all.

The overall picture

Though there are a multitude of apparent home remedies – and, hopefully, more clinically approved treatments to come soon – it’s first important to figure out the reasons for hair loss before jumping into a particular treatment.

“Hair loss is complex,” said dermatology specialist Dr Taylor Bullock, speaking to the Cleveland Clinic as part of the Health Essentials series. “Your treatment will only work if it’s addressing the root cause. That’s why your first step should be getting a medical diagnosis.”

All “explainer” articles are confirmed by fact checkers to be correct at time of publishing. Text, images, and links may be edited, removed, or added to at a later date to keep information current.

The content of this article is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of qualified health providers with questions you may have regarding medical conditions.  

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