research In Vivo Hair Growth Promotion Effects of Ultra-High Molecular Weight Poly-��-Glutamic Acid from Bacillus subtilis (Chungkookjang) 9 citations , March 2015 in “Journal of Microbiology and Biotechnology” Ultra-high molecular weight poly-γ-glutamic acid may help promote hair growth.
research Do Kimchi and Cheonggukjang Probiotics as a Functional Food Improve Androgenetic Alopecia? A Clinical Pilot Study 10 citations , January 2020 in “The World Journal of Men's Health” Kimchi probiotics slightly improved hair density, but more research needed.