Hair loss is one of the most common—and most distressing—side effects people experience after bariatric surgery. If you're noticing more hair in your brush or shower drain, you're not alone. But the good news? It's usually temporary, manageable, and reversible.
Why Does Hair Loss Happen After Bariatric Surgery?
Hair loss after weight loss surgery is typically a condition known as telogen effluvium. It's a fancy term for a process where more hair follicles than usual enter the "resting" phase of the growth cycle, often in response to stress, rapid weight loss, or nutrient changes.
In Australia, bariatric procedures like the sleeve gastrectomy and gastric bypass have helped thousands of people improve their health and lose weight, but the nutritional changes they cause can lead to temporary side effects—including hair thinning.
When Does It Start?
Hair loss usually begins around 3 to 6 months post-surgery, which is right when weight loss is most rapid and nutrient levels are fluctuating. This timing aligns with the natural cycle of hair growth.
How Much Hair Will I Lose?
Most people notice diffuse thinning (hair all over becoming less dense), rather than bald patches. It's uncommon to lose more than 30–50% of scalp hair, and the loss typically slows or stops by month 9–12.
What Causes It?
Several factors contribute to post-op hair loss:
🧬 Nutritional Deficiencies
- Protein: Hair is made of keratin, a protein. Inadequate protein intake = weaker hair growth.
- Iron: Low ferritin (a storage form of iron) is strongly linked with hair thinning.
- Zinc and Biotin: Trace minerals vital for scalp and follicle health.
- B12 and Folate: Important for cellular regeneration.
⚖️ Rapid Weight Loss
Major changes in body weight can disrupt the hair cycle.
😷 Surgical Stress
Your body undergoes physical and metabolic stress from surgery—even when planned and successful.
Can It Be Prevented?
To some extent, yes. Here's how to reduce the risk:
✅ Prioritise Protein
Aim for 60–80g of protein daily, through food and supplements if needed.
✅ Don't Skip Supplements
Australian guidelines recommend lifelong multivitamin use after bariatric surgery. Make sure yours includes iron, zinc, B12, and biotin.
✅ Regular Blood Tests
Work with your GP or bariatric team to check your levels every 3–6 months, especially in the first year.
✅ Stay Calm
Telogen effluvium is reversible. Once the body stabilises and nutrients are restored, hair growth resumes—usually within 6 to 12 months.
When to See a Doctor
Hair loss is common, but excessive or prolonged shedding may signal deeper deficiencies or thyroid issues. Seek medical advice if:
- Hair loss continues past 12 months.
- You experience brittle nails, fatigue, or skin changes.
- You suspect iron-deficiency anaemia (especially common in menstruating women).
The Bottom Line
Hair loss after bariatric surgery is common but not permanent. With good nutrition, the right supplements, and regular check-ups, your hair can—and usually does—grow back.
Think of it as part of the journey: your body is adjusting to massive change, and healing in the process.
🧬 Your body is healing. Be patient, be kind to yourself, and don't forget—this is part of your transformation.
For more advice tailored to your stage of recovery, speak with your bariatric surgeon, dietitian, or GP.
