# Vitamin B7 (Biotin) > Biotin, also known as vitamin B7 or vitamin H, is a water-soluble B-vitamin crucial in metabolizing fats, carbohydrates, and amino acids. It is essential f *Source: [https://www.health3.app/biomarkers/vitaminb7b](https://www.health3.app/biomarkers/vitaminb7b)* ### On This Page - What it measures - Measurement units - Reference ranges - Health impact - Related biomarkers - Scientific references ## What is Vitamin B7 (Biotin)? Biotin, also known as vitamin B7 or vitamin H, is a water-soluble B-vitamin crucial in metabolizing fats, carbohydrates, and amino acids. It is essential for the synthesis of fatty acids and in gluconeogenesis. Biotin also maintains the health of the skin, hair, and nails, influencing their strength and appearance. **Biotin deficiency**, though rare, can result in hair loss, skin rash, depression, lethargy, and neurological symptoms. It can be caused by inadequate dietary intake, prolonged use of anticonvulsant drugs, and genetic disorders affecting biotin metabolism. **Biotin absorption** can be impacted by dietary factors and medications. Avidin, found in raw egg whites, binds to biotin and prevents its absorption; cooking neutralizes avidin. Long-term use of certain anticonvulsant medications can lower biotin levels by altering its metabolism or absorption. Chronic alcohol consumption and factors disrupting gut flora, such as prolonged antibiotic use, might affect biotin synthesis and absorption. **Biotin toxicity** is virtually non-existent, with excess biotin excreted in urine. Managing biotin levels involves dietary sources like organ meats, eggs, fish, nuts, and seeds, or supplementation for those at risk of deficiency. In cases of disrupted biotin absorption, addressing the underlying causes and dietary adjustments are key for maintaining adequate levels. Factors that support healthy **Vitamin B7 (Biotin)** **levels**: - A balanced diet that includes biotin-rich foods such as organ meats, eggs (cooked), fish, nuts, seeds, and certain vegetables like sweet potatoes and spinach supports healthy levels. - For those at risk of biotin deficiency due to factors such as prolonged antibiotic use, chronic alcohol consumption, or genetic disorders affecting biotin metabolism, biotin supplementation under the guidance of a healthcare professional may be considered. - For those who consume raw egg whites regularly, reducing intake or cooking the egg whites thoroughly may help, as **raw egg whites contain avidin, which can interfere with biotin absorption**. ## Measurement Units Vitamin B7 (Biotin) can be measured in: ng/100mL, ng/dL, ng/L, ng%, nmol/L, pg/mL ## Reference Ranges by Age and Gender Reference ranges represent typical values for healthy individuals. Your healthcare provider must interpret your specific results. | Age Range | Gender | Unit | Optimal | Normal | Source | | --- | --- | --- | --- | --- | --- | | All ages | All genders | nmol/L | - | 0.5 - 2.2 | Burnham, 2023 | ## Related Biomarkers - [**Thyroid-Stimulating Hormone (TSH)**](https://www.health3.app/biomarkers/tsh) When supplementing Biotin, this can make TSH appear **falsely low** on some assays.[Zhang, 2020][Ylli, 2021] - [**Free Thyroxine (FT4)**](https://www.health3.app/biomarkers/ft4) Can falsely **increase FT4** results in some tests.[Zhang, 2020][Ylli, 2021] - **Total Thyroxine (TT4)** (Coming Soon) Some total T4 immunoassays are less affected, but supplemental Biotin can interfere with results some of the tests.[Zhang, 2020] - [**Free Triiodothyronine (FT3)**](https://www.health3.app/biomarkers/ft3) May cause **falsely high FT3** on some tests.[Zhang, 2020][Ylli, 2021] - **Total Triiodothyronine (TT3)** (Coming Soon) Supplemental biotin may **falsely raise TT3** on some assay platforms.[Zhang, 2020][Ylli, 2021] - [**Vitamin B5 (Pantothenic Acid)**](https://www.health3.app/biomarkers/vitaminb5p) Biotin and pantothenic acid can compete for absorption in the intestines[Said, 1998]. High levels of one can potentially interfere with the absorption of the other, highlighting the need for a balanced intake of both vitamins to ensure optimal health. ## Related tools - [**Blood Test Unit Converter**](https://www.health3.app/tools/blood-test-unit-converter) ## Academic References 1. Burnham C.-A. D., Chiu R. W. K., Rifai N., Wittwer C., and Young I.. Tietz Textbook of Laboratory Medicine (2023). *Tietz Textbook of Laboratory Medicine*. 2. Patel V. B.. Molecular Nutrition Vitamins (2020). *Molecular Nutrition Vitamins*. [View Source](https://www.sciencedirect.com/book/9780128119075/molecular-nutrition) 3. Zhang Y. Assessment of biotin interference in thyroid function tests (2020). *Medicine (Baltimore)*. [View Source](https://pubmed.ncbi.nlm.nih.gov/32118725/) 4. Dyer D, McCloud E, Moyer MP, Ortiz A, Rubin S, and Said HM. Biotin uptake by human colonic epithelial NCM460 cells: a carrier-mediated process shared with pantothenic acid (1998). *Am J Physiol*. [DOI: 10.1152/ajpcell.1998.275.5.C1365](https://doi.org/10.1152/ajpcell.1998.275.5.C1365) 5. Hosseinzadeh M, Mahdavifar B, Mirzaei M, Salehi-Abargouei A, and Vafa M. Dietary intake of B vitamins and their association with depression anxiety and stress symptoms: A cross-sectional population-based survey (2021). *J Affect Disord*. [DOI: 10.1016/j.jad.2021.03.055](https://doi.org/10.1016/j.jad.2021.03.055) 6. Ylli D. Biotin Interference in Assays for Thyroid Hormones, Thyrotropin and Thyroglobulin (2021). *Thyroid*. [View Source](https://pubmed.ncbi.nlm.nih.gov/34042535/) ### ⚠️ Important Medical Information This reference page is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Reference ranges vary between laboratories. Always review your lab results with a qualified healthcare provider.