Are Rosemary Oil, Herbs and Oils Good For Hair Growth?

Natural remedies for healthy hair have been around for centuries. Long before the hair serums and products of today, people were massaging oils and herbal extracts into their scalps in hopes of growing thicker, healthier hair.

Fast forward to today and many of those natural ingredients including rosemary oil, ginseng and peppermint oil, are having a major moment, showing up in DIY recipes and luxury scalp treatments.  

But do these botanical ingredients really help? Maybe. Certain plant compounds may help create a healthier environment for hair to grow by moisturizing and calming inflammation. Here’s what the research currently says about some of the common herbs and oils touted for healthier hair.

Ingredient	What It May Do for Your Hair
Rosemary oil	Improve blood flow to your scalp Help hair stay in the growth phase longer Support thicker hair
Peppermint oil	Create a cooling feeling on the scalp Increase circulation Help follicles grow hair faster
Castor oil	Moisturize your scalp Reduce dryness and irritation Help hair stay hydrated and less prone to breakage
Ginseng	Activate hair follicle cells Support thicker hair growth
Tea tree oil	Reduce dandruff and scalp buildup Calm irritation and inflammation Help create a healthier scalp
Green tea	Contains antioxidants Protect hair follicles from damage Support hair growth signals

 

Rosemary Oil

The claim: Rosemary oil can stimulate hair growth and reduce shedding

What the science says: Rosemary is an herb known for its anti-inflammatory, antioxidant and antimicrobial compounds. And since it smells pretty great, too, it’s long been an ingredient in beauty products. Studies suggest that rosemary oil may help support hair growth by improving scalp circulation and encouraging hair follicles to stay in the anagen (or growth) phase of the hair cycle longer. When follicles stay in this active phase, hair can grow longer and thicker before shedding.

In one randomized clinical trial, researchers tested formulations containing rosemary and lavender oil as well as rosemary oil combined with castor oil. After about 90 days, participants using the formulations saw improvements in hair growth rate, thickness, density and length.[1] Many also experienced a notable reduction in hair shedding.

Overall, scientists think that rosemary oil’s benefits for hair may come from its antioxidant and anti-inflammatory compounds, which can help protect hair follicles from inflammation and oxidative stress, which can interfere with the hair growth cycle. In simple terms, rosemary oil may help create a healthier scalp environment where hair follicles can do their job more effectively.

Peppermint Oil

The claim: Peppermint oil stimulates hair follicles and helps hair grow more quickly.

What the science says: Peppermint oil is famous for its cooling effect and that’s perhaps part of why it’s being studied for helping with hair growth.

A widely-cited laboratory study found that topical peppermint oil stimulated hair growth in experimental models.[2] Within four weeks, the peppermint oil group showed increased follicle number and depth as well as thicker dermal tissue around the follicles, which are changes that typically happen during the growth phase.[3] The study also found increased activity of insulin growth-factor 1 (IGF-1), a biological marker associated with hair growth.

Researchers think that peppermint oil may help stimulate blood flow to the scalp, which could help follicles transition to the anagen (growth) phase more quickly. Better circulation may also help deliver nutrients and oxygen to follicle cells.

That said, most of the research on peppermint oil and hair growth so far has been conducted in laboratory settings or animal models; larger human clinical trials are needed to confirm whether peppermint oil can have similar effects on hair growth in people.[4]

Castor Oil

The claim: Castor oil can make hair grow faster and thicker.

What the science says: Castor oil has been used for generations in hair and skin care products, and it’s especially popular in natural beauty routines because of its rich texture and mild scent. Scientifically speaking, castor oil is rich in ricinoleic acid, an omega-3 fatty acid that has anti-inflammatory properties.[5] While there isn’t strong clinical evidence that castor oil directly stimulates new hair growth, researchers believe its benefits may come from improving scalp health.

By helping moisturize and hydrate the scalp, castor oil may help reduce inflammation and dryness which can interfere with the hair growth cycle. A healthier scalp environment can help follicles function better and may help prevent premature shedding.[6]
One study found that a rosemary-castor oil combination helped improve hair density and reduce shedding, suggesting that castor oil may help create a supportive scalp environment for hair growth.[7]

In practice, castor oil may work more like a scalp conditioner, helping hair stay hydrated, resilient and less prone to breakage rather than directly stimulating growth.

Ginseng

The claim: Ginseng can stimulate dormant hair follicles.

What the science says: Ginseng has been used for centuries in traditional Asian medicine for its energizing and restorative properties, and researchers have been looking at whether those benefits might extend to hair as well.[8]

Several laboratory studies suggest compounds found in Korean red ginseng, particularly ginsenosides, may stimulate dermal papilla cells.[9] These cells sit at the base of the hair follicle and play a central role in regulating the hair growth cycle.[10]

When dermal papilla cells are active and healthy, the follicle is more likely to produce strong, thick hair. 
Research of herbal hair loss treatments also suggest that ginseng may activate signaling pathways that promote follicle growth while helping protect follicle cells against oxidative stress.[11]

Early clinical trials suggest ginseng extracts may help improve hair density when used in combination with other hair loss treatments. While more research is needed, ginseng is potentially a promising botanical ingredient that may help support the hair growth process. 

Tea Tree Oil

The claim: Tea tree oil can promote hair growth by helping improve scalp health and reducing dandruff or buildup that can impact follicle function and hair health.

What the science says: Tea tree oil is a stalwart in the hair health world. Well-known for its antimicrobial and anti-inflammatory properties, tea tree is a popular ingredient in shampoos and treatments for scalp conditions including dandruff and seborrheic dermatitis; two conditions that may negatively impact hair quality and growth if left untreated.[12] 

A clinical trial published in the Journal of the American Academy of Dermatology found that a shampoo containing 5% tea tree oil significantly improved the severity of dandruff and scalp itching after four weeks.[13] This suggests that tea tree oil may help create a healthier scalp environment for the hair follicles. 

Other research has shown that tea tree oil may help reduce microbial overgrowth on the scalp, which can contribute to inflammation around the hair follicles. Chronic scalp inflammation can disrupt the hair growth cycle so tea tree oil may help hair growth by lowering inflammation and  creating a healthier environment more conducive to healthy hair.

Green Tea

The claim: Green tea can help stimulate hair growth and protect follicles from hormone-related hair loss.

What the science says: Nutritionally speaking, green tea is a powerhouse. It contains antioxidant compounds called catechins and polyphenols, and research has found that regularly drinking green tea may help reduce inflammation and lower the risk of cardiovascular disease, some cancers and manage blood sugar. [14]

When it comes to your hair, laboratory studies have found that a particular catechin called epigallocatechin-3-gallate (EGCG) may help stimulate hair follicles and protect them from the hormone signals that contribute to hair thinning.[15]

One study published in the journal Phytomedicine found that EGCG promoted hair follicle growth and the proliferation of dermal papilla cells, which are at the base of the hair follicle and regulate hair growth.  Additional research found that EGCG may help protect hair follicles from the negative impact of dihydrotestosterone, (DHT), the hormone linked to androgenetic alopecia (pattern hair loss). [16]

Most of the evidence showing green tea has a beneficial effect on hair growth comes from laboratory studies rather than large clinical trials in humans but because the research shows green tea may help protect follicles from oxidative stress and stimulate dermal papilla cell activity it’s included in serums, shampoos and hair-growth formulations.

The Takeaway

Natural oils and herbs have a long history in hair care and modern research is beginning to explain why some may help support healthy hair. Ingredients like rosemary, peppermint, ginseng and green tea appear to potentially influence hair growth via a variety of biological pathways, including calming inflammation and dryness in the scalp to support the follicle cells responsible for stimulating new hair growth. While early studies are promising, most botanicals work best as supportive tools rather than miracle cures. A healthy scalp environment, good nutrition, support from keratin peptides and gentle hair care habits still form the foundation of strong, resilient hair.

Frequently Asked Questions

Do natural oils help hair grow faster?

Some may help but they don’t work the way medical treatments do. Research suggests that certain plant compounds can support hair growth by improving circulation in the scalp, reducing inflammation and making the overall environment conducive to healthy hair growth. But most herbal ingredients have mostly been studied in laboratory settings or small trials so they’re best viewed as supportive for a healthy scalp.

Can herbs or oils help with thinning or hair loss?

They may support a healthier scalp environment but they’re unlikely to reverse hair loss on their own. Topical oils or herbs in hair or scalp treatments may help support healthy hair but if you’re experiencing persistent thinning, it’s best to see a doctor who can help figure out if there’s an underlying cause and recommend treatments.