The viral hair growth trends which actually work, and which to avoid

hair growth trends
These are the hair growth trends to know. (Getty Images)

With social media sites such as TikTok seeing several hair growth trends go viral, it’s easy to get sucked into the hype. Next thing you know, your beauty cupboard is stacked with half-used products and you’re spending your weekend boiling rosemary sprigs to turn it into rosemary water.

Yet, while social media platforms allow for creators to give anecdotal tales of the hair growth remedies that have worked for them (or to peddle something they have been paid to do so), which of these trends actually work?

To find the answers, Hair and Skin Science analysed TikTok data to find the 10 most popular hair growth hacks based on engagement and popularity, from using collagen to castor oil and even booking in for micro-needling appointments.

Below, two trichologists reveal which of these hacks work – and which you should avoid.

Verdict: works.

"Collagen contains amino acids and protein, and it is this that can support hair health," consultant trichologist at UK Hair Consultants, Eva Proudman, says. "Collagen is a quick and easy way of getting protein into the diet to support overall hair health. If protein content is low or restricted by food groups then taking a multivitamin mineral supplement can also be really beneficial."

Verdict: may work.

"Rosemary oil has known benefits for hair but needs applying at least once a day, if not more, to get any visible benefit," trichologist Mark Blake explains.

Proudman advises not to apply rosemary oil directly to the scalp, however. Instead, it should be diluted with a carrier oil first before massaging it into your scalp. "The massage pulls the blood flow into the follicle to stimulate it and it is actually the act of the massage that is more beneficial than the oil," she explains.

Hair loss it cause from family history, hormonal changes, unhealthy of aging.
Too much vitamin A, or retinol, can lead to hair loss. (Getty Images)

Verdict: works.

"This cleanses the scalp and conditions the hair," Blake says. "Scalp health is directly linked to hair health, so a healthy scalp will grow healthy hair."

Proudman warns that some people are allergic to aloe vera, so it’s best to do a patch test fist to ensure you don’t react.

Verdict: may work.

"Retinol is an ingredient that is great at removing sebum, (oil) build up on the scalp," Proudman explains. "The sebum may contain DHT which can exacerbate male or female pattern hair loss."

However, as retinol is vitamin A, too much of this vitamin can cause hair loss, so it’s best to be cautious when using this as a hair growth method.

Verdict: requires further research.

"Caffeine has been well researched in laboratory environments and has shown benefits in terms of penetration into the hair follicle," Proudman explains. "However more research is needed and there is no real data on its effect as an added ingredient in a shampoo. The caffeine would need to be topically applied to the scalp for any benefit and again more research and testing is required."

Verdict: only for use as a professional treatment plan.

"Micro-needling may help hair growth by stimulating platelet activity and definitely helps when used with hair growth factors, as micro needling increases the area of absorption of the hair growth products," Blake says.

Proudman says she would not use this as a stand-alone treatment. "The downside to this kind of treatment is that you are puncturing the skin which can cause irritation and in some cases, infection," she adds.

Verdict: avoid.

"There is no evidence to support that Hibiscus will do anything for hair growth," Blake says.

Close up portrait of beautiful long hair girl in white clothes in field, view from back. Sensitivity to nature concept
Make sure you wash your scalp, not just your hair. (Getty Images)

Verdict: avoid.

While there is no evidence that this can help with hair growth, Blake says when you are washing your hair, think of it as washing your scalp rather than your hair.

"Scalp health is directly linked to hair health. The scalp is a breeding ground for bacteria and yeast and a build-up of this can be detrimental for hair growth," he says.

Verdict: may work.

"Focus on hair serums that need to be added to the hair or massaged into the scalp," Proudman says. "For the hair they can smooth, shine and add real definition as a ‘styling product’ and often contain ingredients like Panthenol or Argan oil."

Verdict: avoid.

"When used in scalp massage, castor oil can help to further stimulate follicular activity but there is no evidence that it will promote hair regrowth," Proudman says. "When used on the hair it will coat the hair to make it feel smooth, however if you use this type of oil then it is also important to remove it from the hair and scalp too."