By Helaine Krasner, MS, RDN, CSOWM, CDN

Potential hair loss after bariatric surgery procedures is a  topic that comes up frequently both before and after surgery. . It’s important that individuals receive accurate information about what is behind this phenomenon that is often the result of stress related hair loss, also known by the medical term telogen effluvium. Understanding the physiological changes at play can help put this often emotionally distressing issue into perspective and can also help reduce the risk factors.

First, let’s address the normal cycle of hair growth. Each hair follicle goes through three stages. The growth phase lasts about four years and is known as the anagen phase. Next is a brief transition where the follicle shrinks, known as the catagen phase. Finally, there’s the four-month resting phase where old hair is shed, known as the telogen phase, making way for a new hair to take its place. At any given time, about 85% of hair is in the growth phase while the other 15% is in the resting phase (1).

Excessive hair shedding can be triggered by metabolic stress, hormonal changes, or medications. This includes stress related to surgery, serious illness or trauma, and calorie or protein deficits. These stressors can disrupt the normal timing of the hair growth cycle pushing hair follicles into the telogen phase prematurely and results in increased amounts of hair shedding for a time, usually beginning three-five months after the stressful event (1).

According to a 2021 systematic review and meta-analysis conducted on hair loss after metabolic and bariatric surgery, 57% of patients report experiencing excessive hair loss within one year of surgery. Younger women are more likely to report this issue. Lab values associated with excessive hair shedding include lower serum levels of zinc, folic acid, and ferritin (a protein inside cells that stores iron) when compared with individuals that did not report excessive hair loss (2).

The good news is that stress related hair loss is temporary and usually resolves on its own within six months as the body adapts and recovers from the stressful event and the normal growth cycle of the hair resumes. No long-term damage to the hair follicles occurs. It’s important to focus on consuming adequate protein (60-80 grams per day or more) and calories after bariatric surgery and to take a good quality multivitamin with minerals supplement daily. It’s also important to continue regular follow-up care that includes checking labs to screen for any potential nutritional gaps. Consulting with a registered dietitian nutritionist can help ensure you are consuming a balanced diet and taking appropriate supplements. Specialized hair vitamins are not recommended or proven to be effective and can even be dangerous. High doses of biotin (a B vitamin) can artificially increase or  decrease the result of many common blood tests, potentially interfering with accurate diagnoses. Seek medical attention if you experience hair loss that does not seem to be improving a year or more after surgery to rule out other possible causes.

To reduce the risk of excessive hair shedding after surgery:

  • Consume adequate protein (60-80 grams/day, or more)
  • Take a good quality multivitamin with minerals supplement daily
  • Continue with follow up care and recommended blood work
  • Discuss any hair concerns with a registered dietitian nutritionist


  1. Hughes EC, Saleh D. Telogen Effluvium. [Updated 2023 May 29]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2023 Jan-. Available from:
  2. Zhang W, Fan M, Wang C, et al. Hair loss after metabolic and bariatric surgery: a systematic review and meta-analysis. Obes Surg 2021; 31(6): 2649-2659.

Helaine Krasner, MS, RDN, CSOWM, CDN is a registered dietitian nutritionist who takes great pride in helping our Bariatric and Medical Weight Management patients achieve their health and weight loss goals.