Google "how to help your hair grow" and prepare to have your mind blown by the sheer amount of information (often conflicting, TBH), tips, and, probably above all, products claiming to offer a miracle solution. Click through and you'll find that horsetail oil is often mentioned as both a topical and oral option. But before we get into the nitty-gritty of this ingredient, let's start with one major disclaimer. There's truly no miracle product or ingredient out there that's going to magically make your hair grow. The closest thing is arguably minoxidil, the only FDA-approved ingredient to actually grow new hair (for those dealing with hair loss). If your goal is simply longer, stronger, thicker strands, your best bet is to take a multipronged approach and address things holistically, with a combination of topicals, supplements, and lifestyle changes. (Not to mention that there's the whole issue of figuring out what's causing your hair issues in the first place. But that's a whole other rabbit hole to go down.)
Back to horsetail oil, though. Turns out, there are some pretty substantial benefits the natural ingredient can offer—but only when taken orally, in supplement form. (And no, there aren't any horse tails involved.) "Horsetail oil is an extract oil, not an essential oil, meaning the extract is taken directly from the horsetail plant via a cold pressing process or by soaking the plant in water or oil to create a tincture," explains trichologist Bridgette Hill. And, for those still wondering, it's called horsetail because the plant branches out, resembling a horse’s mane or tail, explains Hill. It has a long history as an internal, herbal remedy, and has recently gained attention for its potential benefits for hair health, adds board-certified dermatologist Annie Gonzalez, MD, of Riverchase Dermatology in Miami, Florida. So, how exactly can it impact your hair? And how and when should you consider taking it? Ahead, our experts explain everything you need to know.
Type of ingredient: Plant-based extract
Main benefits: Strengthens and improves the elasticity of the hair fiber, helps regulate the hair growth cycle, and reduces inflammation and improves cell turnover to create an optimal environment on the scalp for healthy hair growth.
Who should use it: According to Hill, anyone experiencing hair thinning and/or scalp conditions may benefit from taking horsetail oil as a supplement.
How often can you use it: This is dependent upon the particular supplement.
Works well with: Many supplement formulas combine it with other ingredients beneficial for hair growth, such as biotin and saw palmetto extract.
Don't use with: Consult with your doctor before starting any supplement to ensure there isn't a negative interaction with other supplements or medications you may be taking.
Benefits of Horsetail Oil for Hair
It's worth pointing out that with horsetail oil, as is the case with most herbs and supplements related to hair growth and loss, the benefits are largely anecdotal, says Hill. "That being said, there is very little proven evidence that horsetail oil applied topically leads to healthier hair and scalp. However, there are studies that have shown horsetail to improve hair growth when taken orally," she explains. (Many of these studies focus on the silica and silicon in horsetail oil, more on that in a moment.) Point being, when it comes to horsetail oil, you're going to reap the most benefits if you take it orally rather than use it topically. Here are some of the effects it has.
Strengthens the hair fiber: At the risk of pulling a Captain Obvious, the stronger your hair, the better. The less likely it is to break and snap, the less hair you'll lose. "Horsetail oil is rich in minerals that support the development of the hair fiber, specifically silica," says Hill. It not only strengthens the hair fiber and supports its elasticity, but it also adds sheen and texture. Silica is made of silicon and oxygen; going back to those studies, one 2016 study found that a higher silicon content in the hair was associated with a lower rate of hair loss.
Regulates the hair growth cycle: This one is due to another mineral found in horsetail oil, selenium. "Selenium aids the body in processing iodine, which regulates hair growth. We know that deficiencies in certain minerals, like selenium, can slow down the anagen, or growing, phase of the hair cycle," explains Hill.
Contains collagen-boosting antioxidants: Much of the research around horsetail oil focuses on its antioxidant content and effect in improving collagen synthesis, explains Gonzalez. Why does that matter? Collagen is responsible for keeping hair follicles healthy, she says.
Reduces inflammation and boosts cell turnover: There's no denying that healthy hair starts with a healthy scalp, and horsetail oil works to help create a healthy scalp several different ways. Its both anti-inflammatory and stimulates cellular turnover, so the scalp can operate at its optimal level, says Hill. This in turn creates the ideal environment for the hair follicle to thrive and produce a healthy hair fiber, she adds. And the other benefit? It also makes your scalp simply feel better if you're dealing with issues such as dandruff or an itchy scalp, she points. (Though, FYI, even for these reasons, oral horsetail oil supplementation is better than topical application.)
Hair Type Consideration
Because this ingredient is best taken orally (have we driven that point home enough yet?), it can be beneficial for any hair type or texture, says Hill. Though of course those with thinning hair and/or scalp conditions are the ideal candidates.
How to Use Horsetail Oil for Hair
Both experts we spoke with agree that it's paramount to follow both the directions of the particular supplement you're taking, as well as consult with either your dermatologist or doctor beforehand. If horsetail oil fits into your regimen, your doctor can help you review the supplement options that contain it and indicate the frequency and amount you should take, notes Gonzalez.
Universally speaking, however, you'll want to be patient; studies looking at the benefits of horsetail extract extended over six months, says Gonzalez. That being said, Hill says some results can usually be seen after 90 days; this holds especially true if the major cause of hair loss was due to a result of mineral deficiencies, she says. She's seen particularly noteworthy results in her practice with Viviscal, a supplement that uses horsetail oil as one of its active ingredients; it also delivered proven effects in a 2012 study.