Weight loss and hair shedding: What’s behind the growing concern? Expert explains

Over the past year, more people around the world have been typing one question into Google: “Can Mounjaro cause hair loss?”. Search interest linking Mounjaro and hair shedding has risen by nearly 68% globally, with related queries about GLP-1 medications and hair health climbing even higher.

But what’s really behind this concern? Dr Gizem Seymenoglu, a London-based hair loss specialist, says the answer is more reassuring than many might expect.

“At the moment, there’s no clear scientific evidence showing that GLP-1 weight loss medications directly cause hair loss. Hair shedding is not listed as a primary side effect.”

So why are people noticing changes? Dr Gizem explains that significant physical changes, especially rapid weight loss can temporarily disrupt the body’s balance.

“When the body experiences a sudden metabolic shift, such as noticeable weight reduction, it can trigger a temporary condition called telogen effluvium. It’s essentially the body reacting to change.”

In simple terms, more hairs than usual move into the resting phase of the growth cycle. This shedding often appears several months after the weight change, which can make it confusing.

“Up to 70% of hair can shift into the resting phase after a systemic ‘shock.’ Patients may notice increased shedding, sometimes up to 300 strands a day, but this is typically temporary.”

Another factor may be nutrition. Because GLP-1 treatments work by reducing appetite, some individuals may unintentionally consume fewer nutrients than their body needs.

“If calorie intake drops significantly without maintaining adequate protein and essential vitamins, this can contribute to temporary shedding. Balanced nutrition is extremely important during any weight loss journey.”

Importantly, Dr Gizem emphasises that in most cases, the hair does grow back.

“When shedding is linked to metabolic change or nutritional imbalance, it is usually reversible. Once the body stabilises and nutrient levels are restored, hair growth resumes.”

With online searches continuing to rise, she encourages patients not to panic, but to seek professional advice if they’re concerned.

“Hair shedding can feel distressing, but it’s often part of the body adjusting. If someone is worried, the best step is to speak to their doctor and ensure their weight loss is being managed safely and nutritionally.”