Carlson - Vitamin K2, MK-4 (Menatetrenone), Vitamin K Supplement, Bone & Heart Health, K2 Vitamin, Soy-free, 60 capsules

good

My people seam to think it works well .

I'm glad they make this MK-4 version. MK-7 gives me horrible insomnia, even though other people do just fine on it.

Quick shipping. Very satisfied.

I took this form of K2 (MK7, I copied and pasted from my review for an MK7) for about seven months last year, in an attempt to improve the condition of my teeth. I did a bit of research into vitamin K and after reading many reviews, I decided to try MK7 after using Life Extension Super K for 1-2 months and not seeing much difference. Since the reviews for MK7 and other MK7 versions were so good, I thought everything would be great and kept reordering MK7 without worry.Seven months later, my teeth were horribly WORSE than before. I had developed a huge cavity in those few months that wasn't there before, my teeth were turning brown all along the inner edges, and one of my molars had a chunk of tooth just chip off on its own, on the side of the tooth. I hadn't really paid much attention to my teeth since I thought the MK7 would be taking care of them for me (dumb, yes I know). I never experienced that 'smoothness' on my teeth people always mentioned when taking vitamin K.I freaked out and started researching in earnest, everything I could, and why/how people's teeth were improving on vitamin K. I read Weston A Price, the entire website. I knew food sources of vitamin K + cod liver oil were not enough to rescue my teeth, especially the one huge cavity that started to be painful (definitely a root canal waiting to happen), and then I came across one article on Marks Daily Apple that discussed one woman's experience in saving her teeth with vitamin K, specifically MK4, NOT MK7.After reading that article I immediately ordered Carlson's MK4, which is 5mg per capsule, and started taking three a day, along with the Cure Your Tooth Decay book's emergency protocol of cod liver oil three times a day. The difference in my teeth has been incredible. The huge cavity I have has shrunk, and is now a light brown instead of black, doesn't cause me anymore pain, and all the brown along the inner edges of my teeth have faded away. My teeth are the brightest white they've ever been, and when I run my tongue along them, they are all smooth and clean. Before, when I would floss, the floss would rip and get caught on all kinds of jagged edges between my teeth but not anymore. It's been about 3 months on MK4 but the difference it has made in my teeth is really staggering.One thing I noticed on the MK4 is that I didn't need to take any vitamin D supplements at all, the vitamin K seems to 'magnify' or multiply what little you get from the sun so I would get terrible headaches and pains when taking both D + K, which disappeared when I stopped the vitamin D. I still get some vit.D from the cod liver oil, and it seems to be enough. My theory is that too much vitamin D without a proper vitamin K to balance/utilize it can really screw you up, and I firmly believe MK7 is NOT the right vitamin K to be taking.I also tried Thorne's MK4 drops, both sublingually and transdermally (a la Ray Peat), and it did not seem to be as effective as taking Carlson's orally, at least for me.update June 2017I am still taking this, but alternate between Carlson's and Thorne MK4 drops (taken orally). I have also added a high dose vitamin A (NOW foods 25,000 from fish oil) to balance out the vitamin D I am taking (5000iu every other day), financially I can't always buy the fermented CLO, which if taken 3 times a day is approx 30,000iu vitamin A (retinol forms not beta carotene). I learned that the headaches I would get were from an imbalance in the fat soluble vitamins (A, D, K) and perhaps occasional oxalate dumping - BUT I'm not an expert. I just am happy to have smooth teeth. I still strongly believe MK7 is not the correct form of vitamin K to take and believe my teeth really suffered during the time I took it. I've read articles that mention MK7 is much cheaper to produce than MK4 so manufacturers stand to gain much more profit from it. Also, Weston A Price noticed the 'X-factor' only when humans consumed animal by-products and not plant products, the former being sources of MK4 and the latter MK7. I don't doubt the health benefits of MK7 but I don't think it affects the bone/tooth structure the way MK4 does.

As advertised

Arrived in perfect shape

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.