--- title: "GLP-1 Medications and Hair Loss: Why It Happens and What You Can Do" entity: "blog" canonical_url: "https://www.corefunctionhealth.com/blog/glp-1-medications-hair-loss" markdown_url: "https://www.corefunctionhealth.com/llms/blog/glp-1-medications-hair-loss" lastmod: "2026-09-22T11:53:50.000Z" --- GLP-1 based medications have changed the way we approach medical weight management. They can be highly effective tools for improving weight, metabolic health, insulin resistance, and other cardiometabolic risk factors. But one concern I increasingly hear from patients is: "Why am I losing more hair since I started losing weight?" Hair loss has been reported in patients using GLP-1 based weight-loss medications, including semaglutide and tirzepatide. However, the relationship is more complicated than simply saying, "GLP-1 medications cause hair loss." In many patients, the bigger issue may be what is happening to the body during significant or rapid weight loss. ## 📅 [Book a Discovery Call →](/discovery-call) ## Hair Loss Has Been Reported in GLP-1 Clinical Trials Hair loss is a documented adverse event in clinical trials of some medications used for weight management. In current FDA prescribing information, hair loss was reported in 3.3% of adults receiving Wegovy (semaglutide) 2.4 mg compared with 1% receiving placebo . It was more frequently reported among women than men. With Zepbound (tirzepatide), hair loss was also reported more frequently among women. The FDA prescribing information specifically notes that these hair-loss reactions were associated with weight reduction . A 2026 systematic review examining GLP-1 therapies and hair loss found that semaglutide and tirzepatide had the strongest reported associations. However, researchers emphasized that additional prospective research is still needed to determine causality and understand exactly why this occurs. So yes, hair loss during GLP-1 therapy is something we should take seriously. But that does not necessarily mean the medication is directly damaging the hair follicle. ## Rapid Weight Loss Can Trigger Telogen Effluvium One of the most likely explanations is a condition called telogen effluvium . Hair naturally cycles through different phases of growth and rest. A significant physiologic stressor can cause a larger-than-normal number of hairs to transition into the resting phase. Several weeks to months later, those hairs begin shedding. Common triggers include: - Rapid or significant weight loss - Calorie restriction - Inadequate protein intake - Iron deficiency - Hormonal changes - Thyroid dysfunction - Illness or surgery - Significant physical or emotional stress - Certain medications Rapid weight loss itself is a recognized trigger for telogen effluvium, even in people who aren't taking a GLP-1 medication. That means the rate of weight loss and nutritional adequacy during weight loss matter. ## Eating Less Can Mean Getting Less of What Your Hair Needs GLP-1 based therapies reduce appetite and often make it much easier to eat smaller portions. That is part of why they work. But there can be a downside: patients may unintentionally consume too little protein, iron, zinc, essential fatty acids, vitamins, and overall calories to adequately support lean tissue and normal hair growth. A patient may tell me: "I'm just not hungry." That sounds like the medication is working, but medically supervised weight loss shouldn't simply mean eating as little as possible. The goal should be fat loss while protecting muscle, nutrition and metabolic health. Hair can sometimes provide an early clue that we need to look more closely at what is happening nutritionally. ## 📅 [Book a Discovery Call →](/discovery-call) ## Don't Forget About Iron and Ferritin Iron status deserves particular attention when someone develops increased hair shedding. A person can have a normal serum iron level, or even a normal hemoglobin, and still have relatively low iron stores. That's why I often look beyond just an "iron level." Depending on the individual, an evaluation may include: CBC, ferritin, iron studies and other nutritional markers based on history and symptoms. Low ferritin doesn't automatically mean it is responsible for someone's hair loss, and there isn't one universal ferritin number that guarantees optimal hair growth. However, iron deficiency is a recognized potential contributor to telogen effluvium and should not be overlooked. This is especially important in menstruating women, patients with heavy periods, vegetarians or vegans, and anyone whose food intake has substantially decreased. ## Protein Matters More Than Many Patients Realize When appetite drops significantly, protein intake can drop with it. Hair is primarily composed of the protein keratin, and inadequate protein intake is another recognized trigger for telogen effluvium. Protein also becomes particularly important during weight loss because we aren't just trying to make the number on the scale smaller. We want to preserve lean muscle mass . Protein intake should therefore be individualized based on body size, medical history, activity level, kidney function and weight-management goals rather than relying on one number for everyone. ## Hormones and Thyroid Function May Be Part of the Picture Not every case of hair loss occurring during GLP-1 treatment is caused by the medication or weight loss. For women in their 40s and 50s, the timing may overlap with perimenopause or menopause , when changes in estrogen and androgen activity can affect hair density and growth. Thyroid disorders can also contribute to diffuse hair loss. This is why treating hair loss without investigating the patient as a whole can miss important contributors. Depending on the clinical picture, evaluation might include thyroid testing, iron status, nutritional assessment, menstrual history, hormonal history, medication review and the pattern and timing of the hair loss. ## Should You Take a Hair Supplement? Not automatically. Hair supplements have become a huge industry, but more isn't necessarily better. If hair loss is related to inadequate protein, low iron stores, thyroid dysfunction, rapid weight loss or another underlying problem, adding a long list of supplements without identifying the cause may not solve it. Some nutrients can even become problematic when taken unnecessarily or in excessive amounts. Test when appropriate. Identify deficiencies. Then supplement intentionally. Food should remain the foundation whenever possible. ## Should You Stop Your GLP-1 Medication If Your Hair Starts Shedding? Not necessarily. Telogen effluvium is often temporary and may improve after the triggering stressor resolves and the body adapts. Stopping medication abruptly also may not address the underlying problem. Instead, talk with your healthcare provider about: - How quickly you are losing weight - Whether you are consuming enough calories and protein - Iron and ferritin status - Thyroid function - Other potential nutritional deficiencies - Hormonal changes - Other medications or medical conditions - Whether the pattern actually looks like telogen effluvium or another type of hair loss Persistent, severe, patchy, scarring or otherwise atypical hair loss may warrant evaluation by a dermatologist. ## The Goal Isn't Just Weight Loss This is one reason I believe medical weight management should involve more than prescribing medication and watching the scale go down. We should also be asking: Are you eating enough protein? Are you preserving muscle? Are you getting adequate micronutrients? Are you strength training? Are we losing weight at an appropriate rate? Are there signs that something else needs attention? Successful weight management isn't simply about becoming smaller. It's about improving health while protecting muscle, bone, nutrition, energy, hair and long-term metabolic function. If you're experiencing hair loss while using a GLP-1 based weight-loss medication, don't assume you simply have to accept it. There may be modifiable contributors worth investigating. ## 📅 [Book a Discovery Call →](/discovery-call) ## Understanding Hair Loss During Weight Loss Hair loss can have many potential causes, including rapid weight loss, nutritional deficiencies, thyroid conditions, hormonal changes, stress, medications, and other medical conditions. If you're experiencing increased shedding, identifying potential contributing factors, rather than simply reaching for another supplement, can help guide an appropriate conversation with your healthcare provider. At Core Function Health, I take a comprehensive approach to metabolic, hormonal, and nutritional health, looking beyond individual symptoms to better understand factors that may be affecting how you feel. Based in Seal Beach, California, with virtual care available for eligible patients throughout California. Medical disclaimer: This article is for educational purposes only and does not constitute medical advice. Core Function Health does not advertise or promote GLP-1 medications through this content. Medication decisions should be made with an appropriately licensed healthcare professional. ## References - [Godfrey AK, et al. GLP-1 therapies and hair loss: A systematic review of current evidence and implications for counseling. 2026. PMID: 41998799.](https://pubmed.ncbi.nlm.nih.gov/41998799/) - [Herrera HO, Bordeaux JS. Risk of new-onset hair loss with semaglutide and tirzepatide: A TriNetX cohort study. Journal of the American Academy of Dermatology. 2026. PMID: 41707704.](https://pubmed.ncbi.nlm.nih.gov/41707704/) - [Kang DH, et al. Telogen Effluvium Associated With Weight Loss: A Single Center Retrospective Study. Ann Dermatol. 2024. PMID: 39623615.](https://pubmed.ncbi.nlm.nih.gov/39623615/) - [Asghar F, et al. Telogen Effluvium: A Review of the Literature. PMID: 33541773.](https://pubmed.ncbi.nlm.nih.gov/33541773/) - U.S. Food and Drug Administration. Wegovy (semaglutide) prescribing information. - U.S. Food and Drug Administration. Zepbound (tirzepatide) prescribing information.