The current updated systematic review and meta-analysis aims to investigate the rate of hair loss after metabolic and bariatric surgery (MBS). A systematic search was done on PubMed, Scopus, Google Scholar, and Web of Science. The primary outcome of this study was to investigate the incidence of hair loss following MBS. In this meta-analysis of 41 articles with 7044 patients, our results showed that the incidence of hair loss after MBS was 47%. In addition, Roux-en-Y gastric bypass had a significantly higher rate of hair loss than sleeve gastrectomy (OR = 1.91). On the other hand, Roux-en-Y gastric bypass had a significantly lower rate of hair loss compared to duodenal switch (OR = 0.41). Hair loss is a common complication after MBS, especially after the duodenal switch and Roux-en-Y gastric bypass.