Biotin (Vitamin B7)
Also known as: Vitamin B7, Vitamin H
Biotin is a B vitamin popular in hair, skin, and nail products. Deficiency is uncommon, and benefits in people who are not deficient are unclear. Importantly, high-dose biotin can interfere with certain lab tests, including some thyroid and heart tests.
Snapshot
What this page can tell you: NIH ODS's key biotin point: at higher-than-recommended amounts it can cause false lab-test results (e.g. thyroid), plus its lack of known harm and the antiseizure-medication note.
What it cannot: That biotin thickens hair or strengthens nails — NIH ODS does not establish those benefits for people who aren't deficient. Informational only.
🧩 Stack insights — how this fits into a schedule
Lab-test interference (e.g. thyroid tests) — NIH ODS: biotin above recommended amounts may cause false results in some lab tests, including hormone tests such as thyroid. If you take biotin, tell the lab/provider before blood work. Biotin itself has not been shown to cause harm.
This is a lab-accuracy issue, not a toxicity issue.
Relationship insights are informational only — they describe what is commonly discussed or studied, not what you should take. Not medical advice; review your routine with a clinician or pharmacist.
🕒 Timing
When: Morning, With a meal
Food: With or without food
Timing is flexible.
💊 Common use range
30–100 mcg
Many products contain far higher amounts. High doses can skew lab results — tell your lab/provider you take biotin.
Ranges are informational, not a recommended dose. Talk to a professional about what is right for you.
🤔 Worth considering?
Evidence vs. effort: Limited evidence relative to burden
Popular for hair and nails, but evidence in people who are not deficient is limited. The notable practical issue is that biotin can skew certain blood tests (including some thyroid and heart tests), so tell a clinician or lab if you take it.
A general summary, not a recommendation. Whether something fits your situation is worth discussing with a healthcare professional.
⚠️ Commonly noted interactions (supplements)
None listed.
Often about absorption or timing rather than danger — separating doses is common. This list is not exhaustive.
🧭 Caution level
Ask a clinician or pharmacist before use.
- Thyroid caution category
Caution level is an informational summary of commonly discussed caution categories and doses — not a safety rating, approval, or medical advice. Low caution does not mean safe for you.
🩺 Medication caution categories
None flagged here, but always review your full routine with a professional.
🏥 Surgery & procedure caution
High-dose biotin can interfere with certain lab tests used around procedures; tell your care team you take it.
If you have a procedure scheduled, bring your full supplement list to your surgical and anesthesia team. Do not stop prescribed medication unless your clinician tells you to. Do not start or stop supplements based only on this app.
✅ Quality checklist
- Prefer products with third-party testing or a certificate of analysis (COA).
- Check the label for the exact form and the elemental or active amount per serving.
🧩 Commonly paired with
🔁 Alternatives
🗣️ Questions for a professional
- Is Biotin (Vitamin B7) appropriate alongside my medications and health history?
- Is there a test or check that would tell us whether I actually need it?
🛡️ Safety notes (source-reviewed)
- NIH ODS: biotin above recommended amounts may cause false results in some lab tests, including thyroid-hormone tests — tell your provider/lab before blood work.
- Biotin has not been shown to cause harm; no established upper limit.
- Long-term antiseizure-medication use can lower biotin levels.
⚖️ Evidence limitations
- Benefit for hair/nails in people who aren't deficient is not established by NIH ODS.
❓ Frequently asked
Can biotin mess up blood tests?
Yes — NIH ODS notes biotin above recommended amounts can cause false results in some lab tests, including thyroid-hormone tests. Tell your provider or lab that you take biotin before blood work.
Is there an upper limit for biotin?
NIH ODS does not list an upper limit and says biotin has not been shown to cause harm. The main practical issue is lab-test interference.
🔬 Evidence snapshot
A B vitamin involved in metabolism. Deficiency is rare, and there is limited evidence that supplementation benefits hair, skin, or nails in people who are not deficient.
🚦 Commonly noted cautions (auto)
Thyroid caution category. This item carries a thyroid caution category. If you have a thyroid condition or take thyroid medication, consider discussing it with a healthcare professional. This is a general caution, not a diagnosis or medical instruction.
🧪 Forms & quality
Needs evidence review — no source-reviewed information yet. We only show dose and monitoring details after they have been checked against reputable sources.
See the supplement glossary for what form names like "L-", chelated, or standardized extract mean.
📏 Dose & monitoring
No established upper limit (NIH ODS notes no evidence of toxicity at high intakes). Important: high biotin intake can interfere with certain lab tests.
Evidence vs. burden: Limited evidence relative to burden
😐 Commonly reported side effects
- Uncommon; main issue is lab-test interference at high doses
Non-exhaustive and individual.
🔄 Cycling & breaks
Not typically cycled.
📅 Daily use notes
Pause before blood tests if advised, and inform your provider you take biotin.
📋 Source review status
Source-reviewed — last reviewed 2026-07-02
Placeholder — emphasize lab-interference note.
📚 References
- NIH ODS - Biotin (Health Professional Fact Sheet)NIH ODS — Verified no-UL note, lab-test (biotin-streptavidin immunoassay) interference incl. FDA safety communication, and anticonvulsant interaction.
- NIH ODS — Biotin (Consumer Fact Sheet)NIH ODS — Full text reviewed 2026-07-03. Verified: biotin above recommended amounts 'may cause false results in some lab tests, including those that measure levels of certain hormones, like thyroid hormone'; 'biotin has not been shown to cause any harm'; long-term antiseizure medication can lower biotin levels.
Verified against the source shown. See the research-status page for how review works.
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