Biotin
What’s New This Month
- Heart-attack tests: FDA lists 17 heart-attack blood tests that biotin can throw off. A recall of 465,481 thyroid-antibody test kits, whose instructions wrongly said the problem was fixed, remains open. 1 2
- Regulator reminders: Health Canada (January 2025) says it knows of one death in another country after a false heart-attack test result. The UK medicines regulator (June 2025) told clinicians to ask about biotin before thyroid tests. 3 4
- Injections: Canada pulled unauthorised biotin injections in 2025 and 2026, and FDA lists an ongoing recall of an injectable biotin for lack of sterility assurance. These are not oral supplements. 5 6 7
- Lead lawsuit: A California notice and a lawsuit allege lead in a collagen-biotin chocolate supplement; a supplemental complaint followed in April 2026. These are allegations, not findings. 8
Overview
Biotin is vitamin B7, a B vitamin the body needs to turn food into energy. It is sold as tablets, capsules, gummies and in hair-skin-nail blends. 9
Real deficiency is rare. Risk groups are people with biotinidase deficiency, chronic alcohol use, or long-term anticonvulsant use. 9
It was identified in the 1930s while researchers studied why raw egg white made lab animals ill. 10
Labels claim it grows hair, strengthens nails, clears skin, and supports energy and metabolism.
How We Researched It
We rate each marketing claim with a modified version of GRADE, the system medical researchers use to say how sure we can be (i.e., high, moderate, low or very low), and check each trial with the Cochrane risk-of-bias tool, which asks whether a study’s design could skew its results. For biotin we weighed about 60 records and used 39, published from September 2022 to October 2026. We also checked 10 regulators and safety databases. We found no Cochrane review on hair, nails or biotin deficiency.
Research NotesTop three benefits
Nails GRADE: Very Low
Uncontrolled studies of 2.5 mg a day reported firmer or thicker nails in some users. 9 22 In a 2025 review of 61 patient records, 10% on biotin alone had split nails clear fully, against 70% on biotin plus vitamin B6. 23
Bias check: No controlled trial of biotin alone, and no effect size. A company-linked trial reported gains only as percentages. 24
Hair GRADE: Very Low
The only biotin-alone test lasted 14 days in 10 men and showed no change. 11 A 2026 review of 10 studies found biotin alone did not reliably improve hair. 12
Bias check: Two company-linked trials report large gains with implausible values. 24 25
Blood-test interference GRADE: Moderate
FDA, Health Canada, the UK MHRA and laboratory societies agree biotin can distort some blood tests. 1 3 4 19 A 2026 study found some tests affected below makers’ stated biotin limits. 26
Bias check: How often users are misdiagnosed has not been measured.
Benefit Evaluation
| Claim | Claim Verdict | Research Confidence | Supporting Evidence | Safety Risk | Product Quality | FactStack™ Rating |
|---|---|---|---|---|---|---|
| Nails | Promising | Very Low | Promising | Caution | Variable | Caution |
| Hair Loss from Deficiency | TBD | Very Low | TBD | Caution | Variable | Caution |
| Skin | TBD | Very Low | TBD | Caution | Variable | Caution |
| Brain and Nervous System | TBD | Low | TBD | Caution | Variable | Caution |
| Blood Sugar and Lipids | TBD | Low | TBD | Caution | Variable | Caution |
| Disease Treatment | TBD | Very Low | TBD | Caution | Variable | Caution |
| Thicker Hair in 12 Weeks or 3 Months | TBD | Very Low | TBD | Caution | Variable | Caution |
| Hair | Doubtful | Very Low | Doubtful | Caution | Variable | Warning |
What Sellers Say vs. What Studies Show
| “Biotin grows thicker hair.” | The one test of biotin alone ran 14 days in 10 men and found no change. A 2026 review found biotin alone did not reliably improve hair. 11 12 |
| “Thicker, fuller hair in 12 weeks.” | No trial of biotin alone backs a timed hair result. These claims rest on mixed products or customer surveys. 12 13 |
| “More is better: 10,000 mcg.” | The adult Daily Value is 30 mcg. Retail doses of 5,000 to 10,000 mcg are 2 to 4 times the dose studied for nails. 9 |
| “Biotin is harmless because it’s a vitamin.” | No toxic dose is identified, but it can make some blood tests read falsely high or low, including heart-attack and thyroid tests. 9 1 |
| “Biotin helps with multiple sclerosis.” | The large trial’s main result was not significant. 14 |
| “It lowers blood sugar.” | Fasting glucose did not change significantly across 5 trials in people with type 2 diabetes. Cholesterol fell a little, but two trials also gave chromium. 15 |
Trial ParametersIf you try it
| Who | No marketed health benefit is established. A need is recognised only in biotinidase deficiency, chronic alcohol use and long-term anticonvulsant use. 9 |
| Dose | Adequate intake is 30 mcg a day. Nail studies used about 2.5 mg a day. 9 |
| Ceiling | None established. NIH ODS reports no toxicity up to 200 mg a day; Singapore caps supplements at 0.9 mg a day. 9 16 |
| Duration | Reassess at about 6 months and stop if nothing changes. Stop at least 72 hours before any blood test. |
| Form | Food or multivitamin-level intake. Retail 5,000 to 10,000 mcg is 2 to 4 times the dose studied for nails. Avoid unauthorised injectable biotin. |
| Ask First | Troponin, thyroid, hormone, PSA, tumour-marker or hCG tests: high doses cause false results, including one death after a falsely low troponin. Pregnancy. |
How to Take It
| Pick a plan | Adult need is 30 mcg a day. Nail studies used about 2.5 mg a day. Ask your clinician first. 9 |
| Time of day | Not reported. |
| With food | Not reported. |
| What to expect | Reassess at about 6 months and stop if nothing changes. Studies of nails were uncontrolled. 9 |
| How to take | Stop at least 72 hours before blood work and tell every clinician and lab you take it. Choose a product with an NSF or ConsumerLab check. 17 18 |
Works With / Don’t Mix With
✓ Works with
Not reported. We found no supplement or food shown to add to biotin’s effect.
⚠ Ask first / don’t mix
Blood tests: troponin, thyroid, hormone, PSA, tumour-marker, hCG. Biotin can falsely raise or lower results. 1 19
Thyroid tests. The UK medicines regulator says biotin may interfere with thyroid tests, and the risk rises with higher doses. 4
Chest-pain emergency visit. Tell staff you take biotin, since it can throw off heart-attack blood tests. 1
Manufacturer Recalls & WarningsLast 36 months, newest first
| Date | Maker / Brand | Product | Action | Src |
|---|---|---|---|---|
| Feb 2026 | Hearthy Foods, Inc. | Collagen+ With Hyaluronic Acid + Vitamin C + Biotin | FDA warning letter: manufacturing-practice failures, and labels missing the “dietary supplement” statement of identity. | 20 |
| Oct 2025 | GenoGenix LLC | Biotin for Injection, all strengths (injectable, not an oral supplement) | FDA Class II drug recall D-0048-2026: lack of sterility assurance. Ongoing. | 7 |
| Sep 2025 | Onward Partners; VZ Nutrition (Zeal Naturals) | Multi-Collagen Biotin Vitamin C Chocolate | California Prop 65 notice 2025-03883 alleges lead; a lawsuit was filed in December 2025 and supplemented in April 2026. These are allegations, not findings. | 8 |
| Nov 2024 | Beckman Coulter | Access Thyroglobulin Antibody II test kits (a lab test, not a supplement; 465,481 kits) | FDA Class II device recall Z-0265-2025: instructions wrongly said biotin interference was fixed, so falsely low results were possible. Ongoing. | 2 |
Where to Buy
We compare products side-by-side not just on price, but on whether NSF lists the product as NSF/ANSI 173 Contents Certified (an independent lab confirms the label matches the contents), whether it is NSF Certified for Sport, whether USP lists it as USP Verified, and whether the seller says it is manufactured in the USA. We leave out a brand’s products for this supplement when, in the last 36 months, the FDA took action against that brand over this supplement (a Class I or II recall, a warning letter, an import alert or an advisory letter). We also leave out any brand with an FDA Class II recall or warning letter on any product. We also leave out any product named in a California Prop 65 notice or a non-US recall, along with that brand’s products of the same ingredient and form. Brands with other actions stay listed and are marked in the Recall Screen column. Our goal remains to provide you, the Consumer, with the information and data necessary to make an informed purchasing decision. Prices reflected below are static and subject to change.
Ratings above describe the ingredient’s research, not any product listed below.
| # | Retailer | Product | Price | NSF 173 | NSF Sport | USP | Mfg. in USA (per seller) | Recall Screen | Affiliate link |
|---|---|---|---|---|---|---|---|---|---|
| 1 | Amazon | Nature Made Biotin 1000 mcg, 120 Softgels | Check Price | ✓ | ✓ | ✓ | View on Amazon ↗ | ||
| 2 | iHerb | Thorne, Biotin, 8,000 mcg, 60 Capsules | $28.00 | ✓ | ✓ | ✓* | View on iHerb ↗ | ||
| 3 | HerbsPro | Puritan's Pride, Biotin, 5000 mcg, 60 Capsules | $4.73 | ✓ | ✓ | View on HerbsPro ↗ | |||
| 4 | iHerb | NOW Foods, Biotin, 1,000 mcg, 100 Veg Capsules | $5.50 | ✓ | ✓* | View on iHerb ↗ | |||
| 5 | HerbsPro | Life Extension, Biotin, 600 Mcg, 100 caps | $6.00 | ✓ | ✓ | View on HerbsPro ↗ | |||
| 6 | iHerb | Force Factor, Biotin, 10,000 mcg, 100 Vegetable Capsules | $7.99 | ✓ | ✓* | View on iHerb ↗ | |||
| 7 | Green's Nutrition | Nutricost Biotin Capsules 120 Count | $10.99 | ✓ | ✓* | View on Green's Nutrition ↗ | |||
| 8 | Green's Nutrition | Superior Source Biotin 100 Tabs | $15.69 | ✓ | ✓ | View on Green's Nutrition ↗ | |||
| 9 | Green's Nutrition | Bio Nutrition Biotin 60 Tabs | $16.95 | ✓ | ✓* | View on Green's Nutrition ↗ | |||
| 10 | Green's Nutrition | Pure Encapsulations Biotin 120 Caps | $26.50 | ✓ | ✓* | View on Green's Nutrition ↗ |
Sources
1. Biotin Interference with Troponin Lab Tests – Assays Subject to Biotin Interference (17 tests, 6 makers). US Food and Drug Administration, 21 Jun 2022. www.fda.gov/medical-devices/in-vitro-diagnostics/biotin-interference-troponin-lab-tests-assays-subject-biotin-interference
2. Device recall Z-0265-2025, Beckman Coulter Access Thyroglobulin Antibody II. US Food and Drug Administration (openFDA), 6 Nov 2024. api.fda.gov/device/enforcement.json?search=recall_number.exact:%22Z-0265-2025%22
3. Biotin and the risk of false lab test results. Health Canada, 10 Jan 2025. www.canada.ca/en/health-canada/services/drugs-health-products/medical-devices/biotin-risk-false-lab-test-results.html
4. MHRA Safety Roundup: May 2025 (biotin and thyroid function tests). UK Medicines and Healthcare products Regulatory Agency, 13 Jun 2025. www.gov.uk/drug-device-alerts/mhra-safety-roundup-may-2025
5. Skycare Compounding Laboratories products recall, RA-78029 (BiotinLixer). Health Canada, 4 Sep 2025. recalls-rappels.canada.ca/en/alert-recall/skycare-compounding-laboratories-products-recall-no-market-authorization
6. Unauthorized and counterfeit health products seized at Thumbs Up 4 Shiatsu, RA-81792 (Biacto biotin injection). Health Canada, 25 Mar 2026. recalls-rappels.canada.ca/en/alert-recall/unauthorized-and-counterfeit-health-products-seized-thumbs-4-shiatsu-mississauga-may
7. Drug recall D-0048-2026, GenoGenix Biotin for Injection. US Food and Drug Administration (openFDA), 15 Oct 2025. api.fda.gov/drug/enforcement.json?search=recall_number.exact:%22D-0048-2026%22
8. Proposition 65 60-day notice 2025-03883 (lead), with complaints in case 25CV158783. California Office of the Attorney General, 29 Sep 2025. oag.ca.gov/prop65/60-Day-Notice-2025-03883
9. Biotin: Fact Sheet for Health Professionals. NIH Office of Dietary Supplements, page dated 10 Jan 2022. ods.od.nih.gov/factsheets/Biotin-HealthProfessional/
10. Lanska DJ. The discovery of niacin, biotin, and pantothenic acid. Annals of Nutrition and Metabolism 61(3):246, 2012. doi.org/10.1159/000343115
11. Valentim et al. Biotin, minoxidil or both in 10 men, 14 days per arm. Anais Brasileiros de Dermatologia, 2024. doi.org/10.1016/j.abd.2023.07.008
12. Moltó-Balado et al. Biotin for hair growth in alopecia: systematic review of 10 studies. Dermato 6(2):17, 2026. doi.org/10.3390/dermato6020017
13. Alanazi et al. Oral supplements for hair: review of 14 studies (no biotin-alone study). Journal of Cosmetic Dermatology, 2026. doi.org/10.1111/jocd.70817
14. Cree et al. SPI2: high-dose biotin in progressive multiple sclerosis, 642 people. Lancet Neurology, 2020. doi.org/10.1016/S1474-4422(20)30347-1
15. Zhang et al. Meta-analysis of biotin in type 2 diabetes (5 trials, 445 people). Frontiers in Nutrition, 2022. doi.org/10.3389/fnut.2022.1046800
16. Regulatory overview of health supplements (biotin 0.9 mg a day). Health Sciences Authority, Singapore, 9 Sep 2026. www.hsa.gov.sg/health-supplements/overview/
17. NSF/ANSI 173 certified dietary supplements: biotin (12 products, 7 firms). NSF International, 3 Oct 2026. info.nsf.org/Certified/Dietary/
18. B Vitamin Supplements Review. ConsumerLab.com, updated 22 Sep 2026. www.consumerlab.com/
19. Campi et al. European Thyroid Association guideline. European Thyroid Journal 15(4), 2026. doi.org/10.1530/ETJ-26-0011
20. Warning letter 712415, Hearthy Foods, Inc. (collagen and biotin products). US Food and Drug Administration, 10 Feb 2026. www.fda.gov/inspections-compliance-enforcement-and-criminal-investigations/warning-letters/hearthy-foods-inc-712415-02102026
21. CAERS adverse event reports naming biotin as a suspect (8 reports, Nov 2024 to Mar 2026; for example 2026-CFS-004432). US Food and Drug Administration (openFDA food adverse events), 2024 to 2026. api.fda.gov/food/event.json?search=report_number:%222026-CFS-004432%22
22. Hochman LG et al. Brittle nails: response to daily biotin supplementation. Cutis, 1993. pubmed.ncbi.nlm.nih.gov/8477615/
23. Shemer et al. Biotin, pyridoxine or both for split nails: retrospective study of 61 patients. Journal of Drugs in Dermatology, 2025. doi.org/10.36849/JDD.7687
24. Patel et al. Sesbania extract (about 2.5 mg biotin a day) for hair and nails, 97 completers, 90 days. Cureus, 2025. doi.org/10.7759/cureus.89118
25. Patel et al. Liposomal Sesbania (about 0.75 mg biotin) for hair, 35 analysed, 180 days. Clinical, Cosmetic and Investigational Dermatology, 2026. doi.org/10.2147/CCID.S604770
26. Swallow et al. Biotin interference in laboratory immunoassays. Annals of Clinical Biochemistry, 2026. doi.org/10.1177/00045632261440506
