Hairfluencer social media trends every dermatologist should know in 2021

Dear Editor,

“Skinfluencers” are social media personalities who influence the public on skin‐related topics. “Hairfluencers,” defined as social media participants who draw attention to hair topics such as hair loss, products, and trends, should not be disregarded. As medical credentials are not required for “hairfluencers,” suggestions may include trends that can be harmful or have no scientific backing. In turn, patients may inquire about these trends or may present to dermatology clinics after experiencing negative side effects. Herein, we review social media trends for hair growth and discuss the literature regarding them.

The rosemary trend drives many social media posts and is the most studied of the trends discussed. Rosemary is applied to the scalp and hair or used as a rinse (Table 1). When comparing rosemary oil lotion to minoxidil 2% in 50 males with androgenetic alopecia classified as Hamilton II‐IV over 6 months, both groups demonstrated statistically significant increases in hair counts in a blinded, randomized trial. ¹ However, it is important to note that there is far more evidence supporting the efficacy of topical minoxidil. Two studies assessed essential oil mixtures containing rosemary for alopecia areata (AA). One blinded, randomized, controlled trial with 43 AA participants in the treatment group found improvement in hair growth in a 4‐point assessment scale and blinded photography. ¹ The second was a double blinded, randomized, controlled trial with 20 treatment group participants with localized, patchy AA. Both studies found decreased hair loss surface area. ¹ One case of burning, erythema, pruritus, and irritation was reported in the treatment group. ¹ Another food trend involves onion juice applied to the scalp and hair for hair growth (Table 1). Twenty‐three subjects with patchy AA found 2 months of onion juice applied twice daily resulted in regrowth compared with controls. ² Erythema and unpleasant odor were reported. ² A minoxidil and onion topical, Qilib (Galderma, Fort Worth, Texas), was marketed in the United States but may no longer be available.

TABLE 1.

“Social media hair growth treatments, claims, possible negative side effects. These are not patient care recommendations but instead an overview of social media information that patients may see.”

Treatment for hair growth	Social media reported method of application a	Possible negative side effects	Other claims which may not be entirely based on scientific research	Theorized mechanism of action
Rosemary	Use pre‐packaged oil Or boil fresh leaves Or add leaves to oils (castor oil, flaxseed oil) Spray on the scalp, massage in, leave on the hair or use as a rinse in the shower	Scalp itching, irritation, erythema, and burning 1	Promotes thicker, softer, shiny hair and improves dandruff	Increases perfusion and may prevent dihydrotestosterone from binding to androgen receptors. Also has antimicrobial and antioxidant properties
Onion juice	Blend and strain onions Or mince onions and add to oil (coconut oil, jojoba oil, olive oil) Apply to scalp Optional: Leave on for about 30 min Optional: enhance solution by adding citrus peels or essential oils	Mild erythema, odor, and contact dermatitis 3	Improves dandruff, supports thicker hair, decreases breakage, increases shine, increases collagen production	Antigenic competition
Aloe vera	Extract gel and blend and apply to scalp Or rub open leaf along the scalp Massage and leave in for a variable amount of time (ranging from 15 min to 5 h)	Possible burning sensation, pruritus, allergic contact dermatitis	Improves damaged or dry hair, strengthens hair, increases shine, decreases hair breakage and loss, reduces pruritus and dandruff	Antimicrobial and anti‐inflammatory properties
Rice Water	Boil rice Or soak rice in water Strain and use to rinse hair Optional: enhance the rice water by adding citrus peels and essential oils	Heavy starch may damage the hair	Increases shine, makes hair softer, decreases hair tangle	Contains phenols, which have shown promising results for AA treatment
Castor oil	Use pre‐packaged oil Massage into scalp Optional: Leave for a variable amount of time (ranging from 15 min to overnight)	Hair felting	Reducing hair loss, moisturizes hair, increases hair thickness	Contains ricinoleic acid, which possibly has anti‐inflammatory properties. Also contains vitamin E, which may increase perfusion

^a Not a patient care recommendation.

Less evidence exists for rice and castor oil trends. Rice water reportedly elicited long, shiny hair in the Heian period. ⁴ Rice water is used as a rinse (Table 1). Though preliminary studies of phenols, present in rice, are promising, there is no scientific evidence that rice water leads to hair growth. One abstract, however, reported improved hair friction and flexibility. ⁴ Dermatologists suggest heavy starches may damage hair. Castor oil for hair growth involves massage into the scalp as many believe that vitamin E and ricinoleic acid components increase angiogenesis and decrease inflammation, respectively. However, no clinical studies demonstrating hair growth exist.

Finally, gel from aloe vera leaves applied to the scalp and hair has been popularized for hair growth. No human studies exist, but rats treated with aloe extract exhibited no significant increase in hair density. ³ Burning, pruritus, and dermatitis have been reported with aloe use by humans. ⁵

Overall, there is little to no literature supporting these social media trends for hair growth (Table 1). Dermatologists should be aware of social media trends and the lack of supporting evidence. Additionally, we call on dermatologists, as hair and scalp disease experts, to serve as authorities on “hairfluencer” trends and appropriately counsel patients.

AUTHORS' CONTRIBUTIONS

B.P. and N.H. were responsible for review of the literature and data collection. B.P. wrote the initial manuscript. R.F., N.H., M.H., and N.S. were responsible for manuscript draft edits and finalizing the manuscript. All authors have read and approved the final manuscript.

CONFLICT OF INTEREST

The authors have no relevant conflicts of interest.

ETHICAL APPROVAL

This is a review of the literature. No human subjects were involved in the writing of this manuscript.

DATA AVAILABILITY STATEMENT

Data sharing is not applicable to this article as no new data were created or analyzed in this study.