When it comes to maintaining healthy, full hair, many people turn to vitamins and supplements to fill in nutritional gaps and support growth. But experts warn that taking too much of certain nutrients can actually do more harm than good—especially when it comes to one commonly overlooked culprit: vitamin A.
“While they are essential for hair growth, over-supplementation of certain nutrients can actually cause hair loss,” says Anastasios Moulios, founder of Beardlong. In fact, vitamin A—despite being crucial for vision, immune function, and skin health—can negatively impact your hair when taken in excess. “One of the vitamins that can cause hair loss is vitamin A,” Moulios explains. “Taking excessive amounts of vitamin A supplements can cause hair follicles to go into a dormant phase and stop growing hair.”
Avoid Vitamin A When It Comes To Hair Loss
Vitamin A is a fat-soluble vitamin, which means it gets stored in the body and doesn’t flush out as easily as water-soluble ones. That can quickly lead to a buildup if you're not careful with dosing. While vitamin A is critical for the production of sebum (which keeps the scalp moisturized), too much of it can tip the balance and result in hair thinning or even shedding.
Paul Speed for The Mirror agrees, emphasizing the need to be cautious: “While vitamins and supplements like vitamin A can play a crucial role in supporting overall health and wellbeing, it's extremely important to be mindful of the dosage and potential consequences of over-supplementation.” He adds, “Before incorporating new supplements into your diet, we recommend consulting with a healthcare professional.”

The bottom line
The key takeaway? More isn't always better. Hair loss due to too much vitamin A is a well-documented phenomenon, and it's a good reminder that nutritional balance matters just as much as getting enough of the right nutrients.
Instead of loading up on individual vitamins, aim for a food-first approach and only supplement when necessary—and with guidance from a qualified healthcare provider.


