According to NYU Langone Health, more than 80% of men and nearly 50% of women will face significant hair loss at some point in their lives. This has led to a surge in hair growth vitamins and supplements being marketed as the ultimate solution.

However, experts assert that the path to regaining hair isn’t as simple as just taking a pill.

“Hair loss doesn’t always stem from a lack of vitamins, and simply taking supplements doesn’t ensure hair growth,” explains dietitian Caroline Thomason, R.D., from Washington, D.C., in an interview with YSL News.

So, when can vitamins actually promote hair growth? Health professionals clarify.

Which vitamin deficiencies contribute to hair loss?

As Thomason pointed out, numerous factors can lead to hair loss, and a vitamin deficiency isn’t always one of them.

In men, androgenetic alopecia (commonly referred to as male or female pattern baldness) is responsible for approximately 95% of hair loss cases, according to NYU Langone. For women, that statistic drops to around 40%. Other frequent causes include genetics, hormone imbalances, stress, medications, or various health issues, according to Thomason.

If a vitamin deficiency is the cause of hair loss, it is likely due to insufficient levels of biotin or vitamin D, as stated by board-certified dermatologist Hadley King, M.D., in a conversation with YSL News.

Which vitamins support hair growth?

It’s important to recognize that taking vitamins may not effectively stimulate hair growth if the underlying issue isn’t related to a vitamin deficiency.

If you are dealing with hair loss, Thomason advises first consulting a healthcare professional. They can perform a blood test to check for any deficiencies that could be influencing your hair loss. If a deficiency is identified, then starting vitamins might indeed be beneficial.

According to King, biotin, along with fat-soluble vitamins A, D, E, and vitamin C, can be instrumental in preventing hair loss. Nonetheless, it’s crucial not to self-prescribe vitamins without medical advice, as excessive intake can lead to other health problems, or interfere with existing health conditions and medications.

For instance, excessive vitamin A and selenium can actually worsen hair loss, as noted by Harvard Health. Moreover, taking large amounts of biotin—common in many skin, hair, and nail supplements—may disrupt certain thyroid and hormone lab tests.

If vitamin deficiency is ruled out as the cause of your hair loss, Thomason recommends ensuring that you’re consuming sufficient food, meeting your protein needs, maintaining regular sleep patterns, and managing stress to help prevent hair loss and encourage its growth.