• Regrows and renews stronger hair follicles — Having adequate biotin levels promotes hair follicle health and growth by supporting the function of keratin, the protein that makes hair strong. Without enough biotin hair becomes brittle, thin, and prone to shedding.⁴

• Improves nail thickness and strength — In one study published in the journal Cutis, participants who took a daily biotin supplement for six months experienced a 25% increase in nail plate thickness, highlighting its role in strengthening nails and reducing splitting.⁵

• Supports healthy skin — Biotin contributes to fatty acid metabolism, which is essential for keeping skin hydrated. Deficiency can lead to dry, scaly, red rashes around the eyes, nose, mouth, and perineum.⁶

• Biotin’s influence goes far beyond its enzymatic role — According to a 2024 review published in Nutrients, biotin is “crucial to glucose and lipid utilization in cellular energy production because it modulates the expression of metabolic enzymes via various signaling pathways and transcription factors.”⁸

• Biotin influences immune signaling pathways — It helps regulate how the body responds to inflammation through certain messenger systems. As noted by the researchers, “Biotin modulates the production of proinflammatory cytokines …”⁹

• It shows promise in chronic disease management — Animal studies link biotin to reduced inflammation and improved metabolic function.

“It reduced markers of inflammation and modulated immune responses, suggesting potential applications in conditions such as diabetes, multiple sclerosis, and inflammatory bowel disease.”¹⁰

• Biotin interacts with genetic material to influence the way cells function — According to a 2025 study published in the Journal of Nutritional Biochemistry, biotin directly attaches to histones, which are proteins that wrap around DNA. By doing so, it acts like a dimmer switch that adjusts how strongly certain genes are turned on or off. The research showed that genes linked to DNA repair and protection were more active when biotin was present in sufficient amounts.¹²

• Histone biotinylation plays a role in gene silencing — This is the deliberate silencing of harmful or unnecessary genes. For example, turning off repetitive DNA sequences, which if left unchecked, can cause instability in the genome. Biotin acts as a safeguard, making sure the body’s genetic library stays organized and free of clutter.

• Biotin also supports neurological function — It helps power up pyruvate carboxylase, an enzyme that fuels nearly one-third of the brain’s main energy cycle, giving neurons and support cells the steady energy they need to function. When biotin is lacking, neurological symptoms like seizures and cognitive problems can appear.

• Biotin also helps regulate signaling messengers — This is vital to ensure clear communication between brain cells.¹³

• A study investigating fetal biotin status measured plasma biotin levels in 15 pregnant women and their fetuses during mid-gestation — The results showed that fetal biotin levels were significantly higher than maternal levels, suggesting that the placenta actively transports biotin to the fetus, even when maternal levels are low.¹⁵

• Sufficient biotin during pregnancy may reduce the risk of preterm labor — A retrospective case-control study published in The Journal of Medical Investigation analyzed serum biotin levels in pregnant women with normal deliveries, preterm births, and small-for-gestational-age (SGA) infants.

The researchers found that maternal biotin levels remained low throughout pregnancy, and those in the SGA group had significantly lower biotin concentrations during the second and third trimesters compared to the normal delivery group.

“This study suggests that maternal biotin deficiency during pregnancy might be the risk of preterm labor or fetal growth restriction. Further studies are required to clarify the roles of biotin in perinatal medicine,” the researchers concluded.¹⁶

• A landmark animal study also found that pregnant mice develop marginal biotin deficiency without showing symptoms — Using urinary biomarkers, the researchers concluded that biotin intake during pregnancy may need to be two to three times higher than current recommendations.¹⁷

• High-dose biotin proved helpful in MS patients — In a promising French pilot study published in Multiple Sclerosis and Related Disorders, 23 patients with primary and secondary MS were treated with high doses of biotin (100 to 300 mg a day) over an average of 9.2 months. The results were encouraging and suggest that biotin can impact the disability brought about by MS.¹⁸

• High-dose pharmaceutical-grade biotin has shown encouraging results in clinical trials — In a randomized controlled study, 13.2% of patients with progressive MS reported improvement after nine months of taking MD1003 — “a pharmaceutical formulation of high-dose biotin” — compared to the placebo group. According to the website Multiple Sclerosis News Today:

“Full results of the MS-SPI study are especially remarkable. This is the first time that a drug has reversed the progression of the disease in a statistically significant proportion of patients.

In addition, if we look at the mean Expanded Disability Scale (EDSS) change, the data compare very favorably with all previous trials that looked at the same endpoint. Almost no progression was observed in patients treated with MD1003 for 24 months, and this has never been observed before …

Results … point to the fact that targeting neuron and oligodendrocyte metabolism represents a promising and novel disease modifying therapy approach in progressive MS, particularly in patients with a not-active progressive disease.”¹⁹

• Biotin supplementation improves blood sugar control in Type 1 diabetes patients — A randomized, double-blind, placebo-controlled clinical trial conducted with 70 participants aimed to determine whether biotin supplementation could improve glycemic control and plasma lipid levels in patients with poorly controlled Type 1 diabetes. The findings were promising:

“Biotin administered as an adjuvant in addition to insulin therapy can improve glycemic control, as well as serum lipids concentrations in Type 1 diabetic patients without any side effects.”²¹

• Biotin also shows promise in controlling Type 2 diabetes — A 2022 meta-analysis published in Frontiers in Nutrition reviewed five randomized controlled trials, and found that biotin supplementation significantly reduces fasting blood glucose levels. The researchers note that supplementation “could be economical and potentially beneficial to T2DM patients.”²²

• Biotin also impacts cholesterol profile — The analysis also reported notable reductions in total cholesterol and triglyceride levels among the participants after 28 to 90 days of use. These findings suggest biotin’s potential as a supportive intervention in metabolic health.

• So, how much dietary biotin is recommended? The National Institutes of Health (NIH)’s adequate intakes (AIs) for this nutrient depend on your age and gender. For example, babies up to 6 months old are recommended to get 5 micrograms (mcg) per day; for adults above 19 years old, the AI is 30 mcg. Lactating mothers have slightly higher levels, at 35 mcg.²⁴

• Biotin is found in a wide variety of foods — This is why deficiency is rare for people who eat a balanced diet. In food, biotin exists in two forms — free biotin and protein-bound biotin.²⁵

• Free biotin is mostly found in plant sources — This is the active, unbound form of the vitamin that can be directly absorbed in the intestine and used by the body. Some of the top sources include:^26,27

• Protein-bound biotin comes from animal foods — This type of biotin is covalently attached to a protein or peptide and needs to first be broken down by enzymes into free biotin before it can be absorbed and used by your body. Below are some of the best sources:²⁸

• Know the signs of biotin deficiency — While biotin insufficiency is less common than other nutrient deficiencies, it can still happen. Remember to keep your intake consistent by eating healthy and knowing it’s more available than you think it is. Some signs of deficiency include depression, loss of appetite, nausea, paresthesia, and muscle pain.

• Prioritize your gut health — A healthy gut microbiome contributes to biotin production and absorption. Chronic digestive issues, imbalances in gut bacteria, and excessive antibiotic use can interfere with this. Consuming foods rich in probiotics supports a healthy gut and by extension, more efficient biotin absorption.²⁹

• Take complementary nutrients like zinc and collagen — Biotin doesn’t work in isolation — nutrients like zinc play a key role in supporting hair, skin, and nail health. When combined with a biotin-rich diet, their collective effect can contribute more to comprehensive and lasting health benefits.