Carlson Labs Vitamin K-2,5mg, 180 Capsules

Vitamin K2 plays a key role in the proper distribution of calcium; in particular, it helps to move it out of the circulatory system where it can lead to atherosclerosis and into the skeletal system leading to stronger bones. It is hard to get enough K2 from diet alone and while the body converts some vitamin K1 into K2 the conversion rate decreases with age. Vitamin K2 supplements typically come in one of two forms: MK4 or MK7. Both forms have shown some success in the treatment of osteoporosis. MK4 has a short half-life in the blood of only a few hours whereas MK7 has a much longer half life. In Japan, MK4 is used, by prescription, to treat osteoporosis at a dose of 45 mg/day typically subdivided into three smaller doses whereas MK7 is typically taken is much smaller doses of ~100 micrograms/day. The Carlson capsules contain 5 mg of MK4, so one would need to take 9 per day to match the dose prescribed in Japan (Carlson Labs only recommends taking 1 capsule per day). Even one capsule provides 6250% of the RDA for vitamin K. Presumably the very high dosages were initially explored to counteract the short serum half like of K2/MK4 and research into benefits at lower doses is not yet available. Vitamin K is typically well tolerated at very high doses (K1 does not seem to have an established dose at which it becomes toxic) so for many people greatly exceeding the RDA values won't be an issue. However, Vitamin K interferes with blood thinning medications such as Warfarin, so doses at these levels are dangerous for those taking these medications. Partly for this reason, you don't typically find vitamin K2 in multivitamins. A very strong case can be made for the benefits of supplementation of K2, but optimal dosing and the choice between MK4 and MK7 are murky issues at this time. Supplementing with both MK4 and MK7 may be the best option.

I purchased this product here and was happy with it. It seems MK-4 exists in certain mammalian tissues, with some organs having higher concentrations than others. Experiments with radio-labeled K-1 suggests that it can be converted into MK-4, but probably not at the therapeutic level individuals might seek. The source in supplements seems to be entirely synthetic for MK-4(from a tobacco product I read), because sourcing animal products for it for extraction would be out of sight expensive. The highest food source seems to be "Fois Gras" and has 369 mcg in 100 grams, etc. Geese seem to consume the type of grass and consequently K-1 that their system can convert to Mk-4. MK-9 seems exist in certain cheeses and has a very long half-life. Mk-7 might have a three day half-life it is claimed. MK-4 is said to be prescription in Japan for osteoporosis and typically given at 45 mg a day, in three 15 mg doses. Taking it with oil or fat containing meals seems to have a huge impact on absorption and consequentially utilization. I ordered two shippings of "two month supplies" at the just mentioned dosage, from a different than Amazon vendor, after ordering and partially consuming this Carlson product. I just discovered that Amazon now has vendors, including itself or Prime vendors, that carry the 15 mg/90 capsule bottles, which would be the Japanese monthly dosage for osteoporosis therapeutics. The source, brand, bottler, or whatever is called "Complementary Prescriptions" and can be located with a search on Amazon. The bulk manufacturer is probably based in China, though this isn't documented for the above product, there does seem to be MK-4 manufacturing sources in China, (...and since it isn't stated as being based elsewhere...). edit: In Japan the supplier is "Eisai" who apparently has a patent from the Ministry of Japan. MK-4 is sold in Japan and across Asia under the brand name Glakay.

My people seam to think it works well .

good

This is actually a good product. I am giving it a bad rating because this company has ground my gears with their astromical price hikes. I started taking this in 2015 after reading Dr. Goodman's book on k2 and bone health. This bottle use to be 24.95 then. What annoys me is how they have hiked this product way higher over the years at ridiculous rates. If you do the math it is actually a bad deal. This product is not even the clinical dose for treating osteoporosis as prescribed in Japan. That is 45 mg split over 3 equal doses. The relentless improvement product is one month's supply of that protocol at $45. Doing the math 15mg x 90 pills means there is 1,350 mg of k2 mk4 in that bottle. There are 180 pills at 5 mg in this bottle = 900 mg in this bottle. So for almost $15 more you get the correct clinical dosage for treating osteoporosis. I am 30 year old male. Not trying to treat osteoporosis, but just try to prevent clogged arteries and keep strong bones and teeth as outlined in Dr. Goodman's book sold here on amazon. Mk4 appears to be the active form of k2 as studies are indicating. There is an enzyme that converts mk7 to mk4 in the body, but why chance having a faulty gene prevent you from activating the mk4. I already know I have a faulty methylation gene. Mk4 also has a very short half life in the body so you need to take it throughout the day. TLDR: Good product that works but is a rip off because it is not clinical dosage and has less mg of mk4 than the product that is a clinical dosage. I have been taking for years and I am annoyed by the astronomical price hikes.