Cinnamon for hair growth?
A new study shows that cinnamic acid, a derivative of cinnamon bark, could promote hair growth and offer relief to alopecia patients.
Cinnamic acid is naturally found in cinnamon, which is derived from tree bark. It is an antioxidant phytochemical that protects against certain diseases, such as diabetes.
Chinese cinnamon has been shown to have analgesic properties against colds and shoulder, back, and joint pain. It has also recently been used in cosmetics for its anti-aging effects. Research indicates that cinnamic acid promotes the expression of oxytocin receptors, and oxytocin enhances skin elasticity. However, oxytocin molecules themselves are too large and break down too quickly to be absorbed by human skin.
With this prior research in mind, a team from Japan theorized that cinnamic acid—a smaller molecule—might be able to help promote hair growth by activating oxytocin.
The results of the study were published in Scientific Reports.
25 Percent Increase in Hair Shaft Length
To test the effect of cinnamic acid on hair growth, the research team grew human hair in cultures. They exposed different hair follicles to different amounts of cinnamic acid and noticed that exposure to treatment produced longer hair shafts. Follicloids, hair follicles grown in a culture from cells, exposed to cinnamic acid showed a 1.25-fold increase in the length of the shaft-like structures. The researchers noted that the growth was nearly identical to that in a previous study involving oxytocin, in which follicles grew 1.3-fold.
“These promising results may be useful for developing hair growth-promoting products targeting oxytocin,” Junji Fukuda, the paper’s corresponding author and a professor at the Faculty of Engineering at Yokohama National University in Japan, said in a statement.
The study findings are encouraging in the arena of alopecia treatment, as current drugs often have side effects and limited efficacy. However, hair loss is a major concern for many more people besides alopecia patients; cancer patients undergoing chemotherapy and those experiencing premature hair loss as a result of genetics, diet, or stress may also benefit from less invasive treatments that cinnamic acid may provide.
“The identification of cinnamic acid as a specific component with hair growth-promoting properties holds great promise for enhancing the effectiveness of hair growth products,” Tatsuto Kageyama, the study’s first author, said in the statement. “In addition, the new understanding of the mechanism of hair growth-promoting effects mediated by oxytocin signaling will provide new insights by hair care science and help accelerate the search for new drugs targeting oxytocin receptor expression in the field of drug discovery.”
According to the International Society of Hair Restoration Surgery, more than 2 million people received hair restoration procedures in 2021, including more than 1.5 million nonsurgical medical treatments.
“Less invasive drug therapy is desirable for hair loss treatment, but faces several limitations stemming from side effects and drug efficacy,” the research team wrote.
The team noted that additional research is needed, especially to determine the potential adverse side effects of treatment with cinnamic acid. However, the organic compound is already in use in many products, and no allergic effects have been identified, the team said.
“In future studies, we intend to conduct a comprehensive analysis of gene expression using multiple donor cells from patients with alopecia,” the researchers concluded.