How to use a derma roller for hair growth, according to doctors and trichologists

And while micro needling can stimulate growth factors and improve circulation around hair follicles – which may help support thicker, healthier hair strands – “it tends to work best when there is an underlying thinning process rather than simply trying to boost already healthy hair,” adds Dr Nora.

“If someone has naturally fine hair but no underlying scalp or follicle issue, derma rolling will not fundamentally change hair genetics,” adds Natalia. “In my clinical experience, it is most beneficial where there is early thinning or weakened follicles, rather than purely cosmetic thickening in completely healthy hair.”

Which needle length derma roller is best for at-home use?

“For home use, 0.2mm to 0.5mm needles are the safest and most appropriate,” says Natalia. Here’s a quick guide:

• 0.2mm – 0.3mm derma rollers: Primarily increase transdermal absorption of topical treatments, with minimal impact on follicular stimulation. Since the stratum corneum (the outermost layer of the skin) acts as a natural barrier, micro-needling at this depth helps to temporarily increase permeability, allowing active ingredients to be better absorbed.
• 0.5mm derma rollers: Can provide some degree of stimulation to the scalp by increasing blood flow and activating mild inflammatory pathways, though it does not reach the deeper dermis where follicular stem cells are located.

In professional clinics, longer needles are often used to trigger significant regenerative responses, such as increased collagen production and the activation of growth factors. These should never be used at home due to the risk of infection, excessive inflammation, tissue damage and scarring. “Improper technique or excessive frequency of use can lead to micro-scarring, which may exacerbate hair loss rather than improve it,” adds Natalia.

Who should avoid using a derma roller on the scalp?

“Derma rolling should be avoided if the scalp has active infections, psoriasis, eczema, severe dandruff or open wounds, as micro-needling can worsen inflammation or spread infection,” says Dr Nora.

“It should also be avoided in people who are prone to keloid scarring or those taking blood-thinning medication,” adds Natalia. “In cases of advanced hair loss where follicles are already lost or replaced by scar tissue, derma rolling is unlikely to produce meaningful regrowth, as there is no viable follicle left to stimulate.”

What are the best treatments to combine with derma rolling for hair growth?

According to clinical studies, derma rolling on the scalp produces the best results when combined with the right topical treatments.