Can This Powerful Skincare Ingredient Make Your Hair Grow Faster?

From spot-free skin to fewer lines and wrinkles, the benefits of incorporating retinol into your evening skincare routine are unrivalled. Since bursting onto the scene, the ingredient (otherwise known as vitamin A) has amassed fans in dermatologists, beauty editors and skincare obsessives alike, earning it the 'gold standard' label.

Retinol encourages the growth of shiny new skin cells, fast. This helps improve collagen levels (making skin appear plump and youthful), unclogs pores and shifts hyperpigmentation.

But retinol is not without its downsides. Those brand-new skin cells often come at a price, including potentially flaky skin, redness and irritation, purging (where clogged pores come to the surface) and sensitivity, which is why it's super important to wear SPF during the daytime. Once you find a retinol product that you like, figure out the right percentage and how often you should be using it (skin experts recommend 0.2% twice a week in the evening to start with), and get past any initial teething problems, the results really are unbeaten.

Up until now, the skincare industry has kept retinol all to itself. But lately, haircare brands have started to formulate hair products jam-packed with the wonder ingredient, claiming increased growth, a reduction in hair loss and all-round healthier, stronger hair.

It makes sense. Your scalp is essentially an extension of your facial skin and it should be treated in a similar way. "Your scalp and your face have the highest density of oil glands," says consultant dermatologist Dr Anjali Mahto. She adds that neglecting your scalp, for example forgoing washing or allowing product build-up from hairspray, wax, serum and heat protection, contributes to the overall health of your hair, especially if you're prone to flakes. "If you get a build-up of dry skin, that can impact how glossy your hair is coming through," says Dr Mahto, who also pinpoints oxidation (being exposed to the elements and environmental factors, such as pollution) as potentially damaging to the scalp. Dr Mahto recommends a shampoo like Head & Shoulders Supreme Strength Anti Dandruff Shampoo, £4.99, to get a head start on caring better for your scalp. But where exactly does retinol come in?

Beauty brand MONPURE is one of the first to formulate a hair serum, the Follicle Boost Hair Density Serum, £96, in which the star ingredient is retinol. It's by no means a cheap purchase but it sounds promising, especially if you're looking for a solution to growing your hair. "A healthy condition of the scalp helps with natural growth," says the brand's dermatologist, Dr Sue Ann Chan. But while there have been plenty of studies on retinol in terms of skincare, studies on scalp care are few and far between. "As well as encouraging new skin cells to allow strands to grow through stronger and healthier, retinol has been clinically shown to improve the absorption of other ingredients that can reduce hair loss," adds Dr Chan.

The serum (meant to be used once a day) contains a form of retinol called retinyl palmitate. "There have been studies that have shown that other follicle-boosting ingredients can be absorbed better when combined with retinol," continues Dr Chan. "This can help boost the effects of other ingredients in the formula, such as pumpkin seed extract, which stimulates hair follicles and blocks a hair loss-causing chemical produced by our hormones called DHC. Along with exfoliating lactic acid in the formula, it works to clear the scalp of dead skin and debris, so that hair can grow through thicker and stronger. One study did show that the efficacy of an alopecia drug was enhanced with addition of a topical retinoid in a mild form."

What does an independent hair expert think? "The 'active ingredient in this particular [product] is the pumpkin seed extract, rather than retinol," says Dr Bessam Farjo, of the Farjo Hair Institute. "Pumpkin seed extract is a very weak blocker of the enzyme that converts testosterone to dihydrotestosterone (DHT), and DHT is one of the main culprits in genetic hair loss," says Dr Farjo. "Retinol is used in anti-ageing, as it increases cell turnover. It may also enhance the effects of minoxidil (hair loss medication) on hair growth when mixed together."

In other words, it could have some benefits for hair growth when combined with other ingredients. MONPURE isn't the only brand to formulate hair products with retinol (or vitamin A), though. The VICHY Dercos Nutrients Vitamin A.C.E Shampoo, £11, and Conditioner, £12, contain the ingredient to balance the scalp, which could reduce excess oiliness, as well as vitamin E to moisturise the scalp skin deeply and prevent dryness. Moroccanoil's Hydrating Conditioner, £17.75, is another beauty editor favourite which boasts vitamin A. That said, they are rinse-off products, so the effects may not be as noticeable as a serum or leave-on treatment.

Retinol is traditionally seen as a harsh ingredient and can irritate some skin types, particularly sensitive skin. So would it make your scalp flaky or even sore? "Retinyl palmitate (used in the Follicle Boost Hair Density Serum) is a gentle yet effective form of retinol, making it suitable for most skin types," says Dr Chan. However she notes that if you have a skin or scalp condition (such as dermatitis, itching or psoriasis), seeking advice from medical experts before you use it is important.

When using retinol, it's vital to wear sunscreen during the day to protect new skin cells from UV damage. "Dermatologists would generally recommend strict sun protection and adequate hydration of the scalp skin," adds Dr Chan. "This also helps avoid irritation or discomfort." That's not to say you should be rubbing your facial sunscreen into your hair. Instead, try something like COOLA Scalp & Hair Mist Organic Sunscreen SPF 30, £24, or Malibu SPF30 Scalp Protector, £3.99, alongside your usual hair products if you're exposed to the sun.

While retinol is still under the radar when it comes to haircare, other ingredients are better known and have far fewer potential side effects. The Inkey List's Salicylic Acid Exfoliating Scalp Treatment, £11.99, exfoliates the scalp with BHA salicylic acid and gets rid of flakes, oil and product build-up, making hair feel cleaner and softer. Drunk Elephant's T.L.C. Happi Scalp Scrub, £30, contains lactic and glycolic acid, which exfoliate away dead skin cells, reducing itchiness and dullness, while The Ordinary's Multi-Peptide Serum For Hair Density, £15.80, has countless five-star reviews for boosting hair volume and strength using hair proteins.

If you're experiencing hair loss, psoriasis or any other chronic scalp or hair condition, it's always best to seek advice from a qualified hair expert, rather than attempt to self-treat.