Derma rollers are small rollers with a cylinder covered in micro needles, normally varying between 0.5-3mm in length. It is an original tool for healing acne scars in dermatology. In 1990s, scientists observed that causing micro wounds in the outermost layer of skin induces production of collagen, as the skin tries to repair itself. This micro-wounding produces collagen, the main building material in fibrous connective tissues that makes up our skin. In more recent years, as recently as 2015, clinical studies around androgenic alopecia showed impressive results after using derma-rolling for hair loss over the period of 12 weeks.
Importance of collagen in hair growth
To understand the mechanics and efficacy of derma rolling, we need to understand the importance of collagen first. As the main component of connective tissue, collagen is the most abundant protein in mammals, making 25% to 35% of the whole-body protein content. Collagen molecule consists of amino acids wound together to form triple-helices. It is mostly found in fibrous tissues, such as tendons, ligaments and skin. The name collagen comes from the Greek κόλλα (kólla), meaning “glue”, and suffix -γέν, -gen, denoting “producing”.
We have already talked about why collagen is important in human body and, specifically, in hair growth. Although minimally present in the hair shaft itself, collagen is present around the hair follicle bulb: it thickens around the hair root during anagen, the hair growth stage, supporting growth of new hair. Its importance is key, as the follicle loses a few layers of collagen when hair follicle enters catagen, or the hair shedding, stage.
Mechanics of derma rollers for hair growth
Derma rollers work in two ways – in addition to prompting scalp to produce more collagen and thus supporting the growth stage inside the hair follicle, it also improves blood flow. The epidermis reacts to the wound by sending more blood to the wound to heal it. Therefore, it is highly advisable to apply a solution following your derma rolling routine. On scalp you may consider applying peppermint oil, as it has outperformed minoxidil in promotion of hair growth and hair re-growth. Be wary of skin sensitivity and tingling that peppermint oil may induce. Initially, consider slowly introducing peppermint oil by mixing it up with some other carrier oil, e.g. castor oil, and then further increasing the ratio.
In recent years, scientists have linked the regulation of adult stem cells with hair follicle proliferation and maintenance. In hair follicles, stem cells should to be present and active to become progenitor cells. Progenitor cells help follicle to form hair, even in cases of hair follicle miniaturisation. Micro-needling delivered by a derma roller stimulates production of stem cells that further contribute to higher production of progenitor cells.
Similarly, if derma-rollers is used on skin to aid complexion and acne scars healing, followed by the skin serum it can amplify the effect of the serum and improve penetration and absorption of the active ingredients into your skin.
In-clinic micro needling vs home treatment
If you are unsure about how to do it at home, beauty clinics offer micro needling as a treatment. Because it is delivered by a trained professional, clinics can use larger needles – though the size of the needles is by far not the only definitive factor in ensuring efficacy of micro needling procedure. A professional can also treat hard-to-reach areas, as well, such as back of the scalp.
In the clinical trials for androgenic alopecia, panelists were being treated with the derma-rolling once a week. You might want to increase or decrease the frequency of the procedure based on your own specific scalp reaction. Consider using derma-rolling once a week but no more often than twice a week.
How to derma roll your scalp:
- On dry hair, place the derma roller at the edge of where you’d like to target hair thinning or instil hair growth (e.g. the hairline, or the side of the temples).
- Roll the device slowly over the area, first horizontally then vertically and then diagonally. You should apply enough pressure to penetrate the scalp and feel a slight prickling or tingling, but not enough to cause pain.
- If there is hair in the area, be sure to move in the direction of the hair strands whenever possible to avoid pulling hairs out
- After usage make sure to rinse the roller in warm soapy water and dip it in a disinfecting alcohol solution, and allow the tool to dry
- After dermarolling some people like to apply hair oils, e.g. peppermint or castor to aid hair growth. You can leave the hair oil in until the next time you wash it, or overnight to increase absorption into the scalp
Choosing the derma roller for hair growth
There are various types of derma rollers – ranging by the size of the needles, type of material the needles are made of, as well as the mechanics of the tool itself. Sometimes microneedling can be delivered by derma-stamps – which, as the name suggests – consists of a stamp with microneedles at one end which you stamp your scalp or skin with. It is really a matter of choice and personal preference.
The needles can be made from various materials and high level of hygiene must be maintained when using derma rollers. Washing with soap and disinfecting in an alcohol solution after each use is an absolute must.
Titanium derma rollers
Titanium is a metal which is renowned for being strong, light and corrosion-resistant. It makes it a better material than stainless steel if you have smaller: 0.2-0.3mm needles. Titanium needles rarely become blunt due to wear and tear. As a result, the derma roller can be used for a long time without reducing its sharpness. However because titanium is a hard metal, it is difficult to sharpen the needles, therefore they came out slightly more blunt than their stainless steel counterparts. In addition, titanium is not inherently sterile metal, therefore additional effort must be made in maintaining it clean, sterile and rust-free. Potential bluntness can lead to skin tears and scars, though this matters slightly less from aesthetic point of view, since the area where it is used for is covered by hair.
Stainless steel derma rollers
Stainless steel is a metal which is formed from an alloy of iron and chromium. Stainless steel is legendary for being hygienic – thanks to its inherent resistance to corrosion due to chromium content and the protective film it forms around the outer surface, protecting against tarnishing and rust. Stainless steel needles are also sharper than titanium, though because the metal is softer, the needles tend to go blunt with time. Derma rollers with stainless steel can only be used once or twice (reminder that surgical blades can only be used once because of that). Due of its extreme sharpness and precision, stainless steel micro needles tend to lead to less tears, so better used on skin where visibility of scars is high.
Needle size for hair growth
It is usually recommended to start with smaller micro needles to help hair growth – 0.5mm and then moving upwards only if necessary – in most cases, if you notice that there isn’t enough micro-wounding that occurs. Having said that, moving above 1.5mm it is recommended to reach out to a professional to deliver the procedure as risk of scarring becomes too high.
Speak with your doctor before you consider this treatment, especially if you:
- Have a history of acne, eczema, or open wounds
- Take anticoagulants (blood thinning) and other medication
- Have a condition that slows down healing, e.g. diabetes
- A Randomized Evaluator Blinded Study of Effect of Microneedling in Androgenetic Alopecia: A Pilot Study, https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3746236/
- Response to Microneedling Treatment in Men with Androgenetic Alopecia Who Failed to Respond to Conventional Therapy, https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4458936/
- Minimally Invasive Percutaneous Collagen Induction, https://www.oralmaxsurgery.theclinics.com/article/S1042-3699(04)00101-3/fulltext
- Mixture Toxicity of Methylisothiazolinone and Propylene Glycol at a Maximum Concentration for Personal Care Products, https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6195885/
- Collagen, Wikipedia, https://en.wikipedia.org/wiki/Collagen