Biotin protects the brain from specific damage

The B vitamin biotin reduces neurological brain damage that is caused by manganese and resembles Parkinson’s disease. Although manganese is an essential mineral, excessive intake can act as a neurotoxin. However, according to a study published in Science Signaling, biotin appears to have a therapeutic effect on Parkinson-like symptoms by promoting the production of the neurotransmitter dopamine, which is important for the nervous system and mood.

Manganese is an essential mineral involved in energy metabolism, bone health, connective tissue formation, and antioxidant functions. Most people seem to get enough manganese from their diet. However, excessive manganese can become toxic to the body, as excess amounts accumulate in specific nerve cells, leading to their destruction. This condition, known as manganism, results in symptoms such as tremors, muscle stiffness, and cognitive disturbances, resembling Parkinson’s disease and therefore referred to as Parkinsonian syndrome.
In the new study, researchers specifically demonstrated how manganese can damage the nervous system. The study also showed that the B vitamin biotin may have a protective effect by counteracting manganese-induced neurological damage.
Excess manganese is not typically obtained through regular diet, but inhalation from welding fumes, industrial work, mining, agricultural pesticides, and water from certain wells can lead to excessive exposure and increase the risk of Parkinsonian syndrome.
Previous research has shown that manganese can bind to a specific protein (alpha-synuclein), causing it to misfold and accumulate in the brain. Misfolded proteins of this kind have also been linked to the development of Parkinson’s disease.
Using fruit flies, researchers developed a model mimicking the severe effects of manganese exposure in humans. They found that excessive manganese triggers motor difficulties, dysfunctions in cellular mitochondria and lysosomes, loss of nerve cells, and reduced lifespan.
These findings were later confirmed using human dopamine-producing nerve cells derived from stem cells. Here, too, excessive manganese was shown to destroy these nerve cells. The loss of dopamine-producing nerve cells, which are normally found in the brain's substantia nigra, is a hallmark of both Parkinson’s disease and Parkinsonian syndrome.

Biotin’s positive effect on the nervous system and dopamine production

Biotin, also known as vitamin B7 or B8, plays a role in energy metabolism, the nervous system, mood regulation, skin, hair, and mucous membranes. Biotin is typically found in organ meats, eggs, fish, whole grains, mushrooms, vegetables, and nuts. Additionally, certain gut bacteria produce biotin, which enhances the brain’s dopamine production via the gut-brain axis.
According to the new study, biotin supplements specifically counteracted neurotoxic damage in fruit flies and stem cell-derived nerve cells by improving mitochondrial function and reducing cell loss.
The researchers suggest that biotin supplementation may offer a new therapeutic approach to counteract neurological damage caused by excessive manganese exposure. Moreover, biotin is a safe, simple, and inexpensive treatment, though further studies are needed to explore its potential.

B vitamin supplementation as part of Parkinson’s disease treatment

This new study aligns with other recent research suggesting that Parkinson’s disease is caused by dysfunctions in multiple systems. Early symptoms often originate in the gut, with changes in gut flora and the intestinal lining contributing to disease development over time.
According to a Japanese study, Parkinson’s patients lack certain gut bacteria involved in the synthesis of biotin and vitamin B2. Additionally, supplementation with these B vitamins may help prevent and treat Parkinson’s disease.

References:

Yunjia Lai et al. Biotin mitigates the development of manganese-induced, Parkinson’s disease-related neurotoxicity in Drosophila and human neurons. Science Signaling 2025

University of Rochester Medical Center. Biotin may shield brain from manganese-induced
damage, study finds. ScienceDaily 2025