Legal status · United States
Is Vitamin K2 legal in the United States?
Written by Aaron CuhaReviewed Sep 2026
Direct answer
Vitamin K2 can be sold in the United States as a supplement or cosmetic ingredient. Its legal category is "Sold as a supplement". That is not approval as a drug. FDA has not checked any health claim made for it. Versions you inject, and "research use only" versions, fall outside supplement rules, so that label does not make them legal to use in people. On the evidence, no completed trial in people is cited on its profile (2 human records with no result or no dose given).
- People given it
- 0
- Found nothing
- 0
Legal category
Sold as a supplement
Do not take it with blood thinners that work by blocking vitamin K, such as warfarin, unless a doctor says otherwise.
Reviewed Sep 2026. This is a legal category, not legal advice.
A "research use only" label on a vial does not make it legal to use on people.
Vitamin K2 in the United States at a glance
| Legal category | Sold as a supplement |
|---|---|
| Note | Do not take it with blood thinners that work by blocking vitamin K, such as warfarin, unless a doctor says otherwise. |
| FDA approval status | Sold as a dietary supplement in the United States. Not approved to prevent heart disease or broken bones. Warfarin is still a prescription blood thinner, and K2 can throw it off. |
| Studies in people | 2 of 2 sources on the profile |
| Reviewed | Sep 2026 |
The legal category and note come from the Vitamin K2 profile. We checked them against U.S. Food and Drug Administration (FDA) listings on the reviewed date.
What this means
- 01
Vitamin K2 can be sold in the United States as a supplement, food or cosmetic ingredient, under the legal category above. It has no approval as a drug.
- 02
Being sold as a supplement means FDA has not checked any health claim. The makers are responsible for safety and labels, and quality varies from product to product.
- 03
Versions you inject, and "research use only" versions, are not supplements. That label does not make them legal to use in people, and anything you inject falls under the rules for medicines.
What Vitamin K2 is
The K2 half of Aaron's vitamin D3 plus K2 pairing. In the Rotterdam Study, people who ate more K2 in their food had less heart disease. In a three-year trial, healthy women past menopause who took K2 (as MK-7) lost less bone. If you take the blood thinner warfarin, K2 is off the table.
Vitamin K2 is a family of related vitamins called menaquinones. The one most often sold is MK-7.
How it works: Vitamin K helps switch on certain proteins, including clotting factors and osteocalcin, a bone protein. MK-7 is a long form of K2 that stays in the blood longer than MK-4.
Approval history: Sold as a dietary supplement in the United States. Not approved to prevent heart disease or broken bones. Warfarin is still a prescription blood thinner, and K2 can throw it off.
How FDA treats this kind of product
Approves prescription drugs, each for a named use. It also acts against unapproved products, including peptides sold online. Compounding pharmacies, which mix drugs to order, may make some compounds with a prescription. That only applies when the FDA puts the compound in a category of bulk ingredients it allows.
The legal category above is how The Longevity Archive reads U.S. Food and Drug Administration listings for Vitamin K2 on the reviewed date. It is not a legal opinion. Rules change. Bringing a compound into the country, prescribing it and owning it can each be treated differently. Check with the agency before you act on anything here.
Vitamin K2 in sport and the military
Whether Vitamin K2 is banned in sport is set by the World Anti-Doping Code and by military rules, not by its legal status in the United States. Before you compete or get tested, look up Vitamin K2 by name on the Prohibited List, or look up a named product in Global DRO. Under the World Anti-Doping Code, category S0 bans, at all times, any drug-like substance that meets two tests. No other section of the List covers it. And no government health regulator anywhere has a current approval for it as a treatment in people. Many substances that are approved somewhere are banned by name in another section. So approval does not mean a substance is allowed in sport.
- WADA Prohibited List
- Global DRO (check a named product)
- USADA (US athletes)
- Operation Supplement Safety (US service members)
The rules you compete or serve under decide this, not this page.
Vitamin K2 in other countries
Frequently asked questions
Is Vitamin K2 legal in the United States?
Vitamin K2 can be sold in the United States as a supplement or cosmetic ingredient. Its legal category is "Sold as a supplement". That is not approval as a drug. FDA has not checked any health claim made for it. Versions you inject, and "research use only" versions, fall outside supplement rules, so that label does not make them legal to use in people. On the evidence, no completed trial in people is cited on its profile (2 human records with no result or no dose given). Note: Do not take it with blood thinners that work by blocking vitamin K, such as warfarin, unless a doctor says otherwise.
Can I buy Vitamin K2 in the United States?
Yes, as a supplement or cosmetic. In the United States, Vitamin K2 has the legal category "Sold as a supplement". So products you swallow, put on your skin or use as a cosmetic can be sold under supplement rules. Versions you inject, and products labeled "research use only", are not supplements. They are not approved for use in people. Note: Do not take it with blood thinners that work by blocking vitamin K, such as warfarin, unless a doctor says otherwise.
Is Vitamin K2 FDA approved?
No. FDA status: Sold as a dietary supplement in the United States. Not approved to prevent heart disease or broken bones. Warfarin is still a prescription blood thinner, and K2 can throw it off.. Current US legal category: "Sold as a supplement". On the evidence, no completed trial in people is cited on its profile (2 human records with no result or no dose given).
Related compounds in the United States
Full research profile
How Vitamin K2 works, the studies we cite, FDA status and the full legal summary are all on its compound profile.
Vitamin K2 profileThis page is general information about the legal status of Vitamin K2 in the United States, current as of Sep 2026. It is not legal advice. Legal status changes. For your own situation, check with U.S. Food and Drug Administration or ask a lawyer. Educational use only. This database summarizes published research and is not medical advice. Where a dose appears it is a record of what a trial or clinic ran, or what people describe doing, with its source attached. Nothing here is a recommendation for personal use. Sellers named on the price pages are ranked by certificate tier, then price, and any affiliate income is disclosed there. Naming a seller is not a recommendation to buy or use anything.