Share ConsumerLab.com's information with family and friends — or just send to yourself. Simply provide an email address below.
You must provide a valid email address.
Your email address*:
Your name*: Send me a copy
Email Address where it's going*:
*Addresses and name will only be used for sending this message.
Additional message (optional):
Your message has been sent. Thanks for sharing!
Question: What is the difference between forms of vitamin K2?
Answer: Two forms of vitamin K2 are typically found in supplements: MK-4 (synthetic) and MK-7 (natural, from natto). There are significant differences between them: in paticular, MK-7 has a longer half-life, so a smaller dose can be used. Two newer forms of MK-7 are available that are synthetic. Get the details in the Review of Vitamin K Supplements, which includes our tests and comparisons of products containing both forms of K2 as well as vitamin K1.