Biotin for Hair Growth: Does It Work

Biotin may support hair growth in people whose hair thinning or loss occurs due to a biotin deficiency. Other vitamin deficiencies may also affect the health of your hair.
Most of the products contain multiple ingredients. Biotin, a water-soluble B vitamin, is almost always one of them.
Similarly, many shampoos and conditioners that promise thicker, fuller hair often contain this B vitamin.

The reoccurring theme here is that biotin, whether taken as a supplement or lathered in your hair, supposedly benefits hair growth.
This article explains the link between biotin and hair health and whether the vitamin is effective and safe for hair growth or preventing hair loss.

What research says about biotin and hair growth
Biotin has many benefits for your body.
Its primary role is to help turn the food you eat into energy. Your body also needs it to produce keratin — the type of protein that makes up hair, skin, and nails (1Trusted Source).
Many foods contain biotin, meaning that deficiency is rare in healthy people who eat a balanced diet (2Trusted Source).

Although rare, biotin deficiency can cause skin rashes, brittle nails, as well as hair thinning and loss. This owes to the vitamin’s role in keratin production (2Trusted Source, 3Trusted Source).
As such, biotin supplements and biotin-added hair products are commonly advertised to support healthy hair growth or promote thicker, voluminous hair.

Despite these claims, though, there’s limited evidence to suggest that supplementing with biotin or lathering it through your hair promotes hair growth in non-deficient people.
Does biotin help prevent hair loss?
Although the evidence to support biotin alone for hair growth is weak and limited, the evidence is slightly stronger for preventing hair loss.

Still, biotin supplements are only likely to prevent hair loss and promote hair growth in people with a biotin deficiency.
In one study, a biotin deficiency was found in 38% of women complaining of hair loss. Of these participants, 11% had a history of deficiency risk factors, such as inflammatory bowel disease (IBD) or the use of certain medications like antibiotics (5Trusted Source).
While this study didn’t assess the effects of biotin supplements or biotin-added hair products on preventing hair loss, it demonstrates the link between hair loss and inadequate biotin levels.