Starting a GLP-1 treatment and noticing more hair in your brush or shower drain? You are not alone. Hair loss during weight loss with these medications is more common than most people expect, and in most cases it is temporary.
What causes it
The main reason is what doctors call telogen effluvium. When the body experiences significant stress, such as rapid weight loss, it can pause hair growth and shift more strands into the shedding phase. The result is diffuse, generalized hair loss that typically appears two to four months after the triggering event.
This differs from genetic balding, where loss follows a pattern and strands gradually thin. With telogen effluvium, you lose hair diffusely across the entire scalp. The strands fall out but the scalp itself looks normal.
Nutrients that matter
Hair loss related to GLP-1 almost always has a nutritional component behind it. When you significantly reduce calorie intake, the body prioritizes vital organs and reduces investment in hair and nails.
Zinc, iron, biotin, and protein are the nutrients most associated with hair follicle health. Protein is especially important because hair is made of it. If you have been eating much less than before without proper planning, you are likely below the protein target needed to maintain hair and other tissues.
Biotin supplementation only makes sense if you have a confirmed deficiency. In excess, biotin can interfere with thyroid tests, so it is not something to take without guidance.
What you can do in practice
In your diet, prioritize foods rich in iron and zinc: meat, eggs, legumes. If you followed a restrictive diet for years before GLP-1, you may have had low stores of some nutrient that are now showing up.
In your habits, it is worth reducing heat styling tools. Heat damages hair, and if strands are already thinner because of effluvium, it accelerates breakage. Very tight hairstyles also contribute to mechanical hair loss.
If you use PeptPro, the side effect monitoring feature lets you log symptoms with date, time, and intensity, linked to your dose. This record is useful to show your doctor if the loss coincides with a specific phase of treatment or dietary changes. Get the app here.
PeptPro also lets you log what you ate in preceding days and spot patterns. If you have been eating very little for weeks, the app helps you see that in your meal history.
When to seek help
If the loss is very severe, with noticeably thinner areas, or comes with other symptoms like extreme fatigue, weak nails, or skin changes, see a dermatologist or endocrinologist. There may be another cause beyond treatment, such as thyroid dysfunction or iron deficiency unrelated to GLP-1.
Visible hair changes take three to six months to appear after the problem causing the loss has been resolved. This means patience is part of treatment. Hair lost to telogen effluvium grows back once the body realizes it is in a less stressed state with enough nutrients.
PeptPro keeps everything in one place: symptoms, dose, meals. Instead of relying on memory, you open the app and have an organized record to bring to your appointment. Start here.