(Edit: See updates at the end.) My primary objection is that it contains alfalfa. I only saw one reviewer complain about this when I was trying to decide whether I should buy or not, and their complaint was about the fact that alfalfa contains Vitamin K1 and not K2. My complain is different, and it wasn't something I understood at the time of purchase. I knew nothing about alfalfa. The actual product contains 100mcg K2 300mg alfalfa per pill and a small amount of Vitamin C (the primary nutrient that boosts iron absorption). What's wrong with alfalfa? Well, it contains a large amount of iron (7% of recommended daily value in 100g alfalfa; this product contains 300mg per pill). What's wrong with iron? Just like Vitamin K2 is under-recognized in our society for its MANY health benefits (including being an anti-oxidant and supporter of calcium utilization / bones), iron is under-recognized as an oxidant and a danger to our health. I found this out the hard way. Before I go into that story, let me just say that our bodies require a delicate balance of iron. Because iron deficiency is so common, iron toxicity goes under the radar as a prevalent health issue. But my research over the past few days as well as consultation with a nutritionist as well as my experience has made me aware that iron is THE primary source of oxidative stress in food, notwithstanding "partially hydrogenated" junk "food." Furthermore, iron is found in significant quantities in nearly all foods and is difficult to avoid, but 21% per pill? That's a LOT! Especially if you're planning on taking 2-3 of these per day!!!!! Unless you're anemic or at risk of becoming anemic soon, you do NOT need to be getting that much iron just in order to consume K2!!! Especially if you are a male or post-menopausal female! Please, let me consume my K2 in PEACE, and consume iron as I choose, separately. Nextly, let me note that I have just done some research and found out that Vitamin K2 is a powerful antioxidant, and this is one of the primary reasons that it's known as a super vitamin. Have you been reading about how Vitamin K2 not only prevents osteoporosis, but prevents WRINKLING, or even heart disease and diabetes? This is due to its antioxidant effect. Iron oxidation promotes free radicals which then damage your cells, your skin, your neurons, your liver, your heart, etc. etc. It also increases diabetes by destroying cells that regulate glucose. I placed an order for this supplement on the same day I got a call from my doctor saying that my blood results were the same as the last two times: slightly small red blood cells and slightly low hemoglobin, although my iron was "normal." She just told me to take a multi, but I'd been doing so, so I was convinced it just wasn't enough. I researched how much an anemic person would take and started taking more. Within just 7 days, even though I wasn't taking a radical amount of iron supplements, I started experiencing dramatic symptoms that correlated to everything I read about iron overload. This product arrived in the mail on the same day that I realized I'd definitely taken too much iron and stopped taking it. I took the K2 pills for 2-3 days before realizing I wasn't feeling better and researching whether the alfalfa contained iron. Then I stopped taking the pills. Yet, I continued to feel worse. I went back to my doctor and got a new blood test. The blood draw made me feel better until I ate dinner, and I just felt worse and worse. I went to the ER a few days later because I couldn't wait for my test results, and I was told my iron was fine and my symptoms weren't related to iron. I reviewed my test results a few days after that and again my doctor said my iron was fine, etc. (Bear with me...) I had by this point found out that I have 6 family members on the Chinese side who have thalassemia minor, a genetic trait causing "small red blood cells," which I probably have. But my doc didn't want to consider it since I had in fact by slightly low in iron - however, my hemoglobin jumped up to 15 (high end), while my blood cells got slightly smaller. I found out that my mom who has diabetes (people with thalassemia have double the rate of diabetes) had been told to take iron pills last year even though she stopped menstruating three years ago. Her doctor said it wasn't working and told her to take more. People with thalassemia are often told to take iron due to their small red blood cells. She started going blind at the same time she started taking this iron last year. My aunt was told to take iron, but it made her sick. My brother took iron and starting bleeding through his urine. I tried to argue with my doctor, what if I have iron overload but it's just not showing up on the test. Why am I getting sicker and sicker even though I have been avoiding iron like the plague, and my doctors keep saying it's not the iron, yet all symptoms match iron overload?!?! THEN I spoke with my nutritionist and told her my body must've been really inflamed because Aleve (anti-inflammatory) was helping and also my veins swelled like marbles in the ER the other night. She said, "Yeah... Iron is an oxidant. Oxidation causes inflammation." And people with thalassemia are more sensitive to iron overload and oxidation for several reasons. I believe some of the symptoms listed for "iron overload" are actually due to iron oxidation. Anyway, today I found out Vitamin K2 is a powerful antioxidant and started taking it again. I took three pills today. Then I started itching again and feeling more heavy-headed (symptoms of iron oxidation and/or overload) right after taking the third pill and then looked up the alfalfa again. Last time I hadn't figured out exactly how much iron was in alfalfa and read conflicting info on whether it was or wasn't a significant source. But the Wikipedia article on alfalfa says 7% per 100mg. Vitamin K2 is an atypical antioxidant in that it doesn't oxidize itself (like Vitamin C or E), but rather it blocks the oxidative stress / free radicals from building up in your system. I think I will keep taking this supplement for at least a day or two in smaller amount than I took today (combined with loads of tea to block iron absorption), but if I don't get better, with this powerful antioxidant and a moderate iron intake, I'm going to blame this supplement for failing me in its antioxidant properties. And then I'm going to order a different product that doesn't contain alfalfa. I might add a star to this rating (rounding up to 4) if I do get better soon, but probably not. I think 3.5 is accurate. Vitamin K2 MK-7 is a wonderful substance, but unless you're low in iron, this product fails. Either way, it loses out on some potential antioxidant effect and potentially becomes more powerful as a dangerous oxidant than as an antioxidant, by adding in the 300mg alfalfa. Why is the alfalfa in there anyway if it only contains K1? to make the pill look bigger? A marketing tactic? For good luck? At least they didn't need to put that much! I just took 63% of my daily value of iron in those three pills!! By the way, women live longer than men everywhere because they menstruate out their iron!! Also, I'm not sure I've noticed any positive effects on my bones or teeth in the short time I've taken this. Excess iron can be bad for your bones and teeth as well - it can actually cause loose teeth not to mention Arthritis. Maybe that's why one reviewer stated that MK-4 supplement did better for their teeth!! I will update here if I notice any significant gains or losses in my teeth/bones that I believe are related to this supplement. Update November 3: I ended up discontinuing the K2 after this review since I continued to feel pretty awful afterward. I have just ordered some new K2 products without iron contents since I don't want to risk it until I can detoxify my body thoroughly. Update November 4: The plot thickens. I have just started researching negative side effects of MK-7, and apparently while there are no recognized studies on this, a lot of people have reported experiencing various negative side effects from MK-7, more so than MK-4, precisely because MK-7 builds up in the body. Its half-life is 3.5 days and so should only be taken once or twice a week at 45-100mcg doses. Most of the symptoms of bodily stress I've been experiencing started the same day I first took this supplement. Now, I had already been eating excessively high amounts of fermented cheeses, as well as natto, while waiting for my MK-7 supplement to come in, so by that point I may have already had more MK-7 than I needed. I thought this supplement would be easier. But I kept reading how there were no known upper limits to K2 consumption and that MK-7 was better because it lasts longer, and I figured the Japanese who eat natto were using MK-7 in their unique osteoporosis treatments, so I thought it was okay. Turns out, upon delving deeper, that the medically prescribed treatment for osteoporosis in Japan is actually MK-4. Anyway, some of my negative symptoms also match up to people's negative experiences of MK-7, so I'm gonna try at least a few days to a week without eating any foods containing significant amounts of MK-7 and see if I start to get better. I know not all of the symptoms are from that, but my combined dietary changes all one after another may have all just made this really, really bad and hard to tell what caused what. Maybe the high calcium intake from cheeses and a small number of calcium tablets plus MK-7 are partly to blame for muscle cramps, chest discomfort, and joint paints. I'm also expecting to get a new blood test in a few days, so together with my doctors and nutritionist, I'll figure this out soon. I may have to lower the rating on this product to less than 3.5 if I find out it's one of the culprits for not only iron contents, but MK-7 itself. Stay tuned. I wouldn't recommend this product in the mean time - at least, don't take it more than 1-2 times a week. Update Nov. 5: Yeah. End of second day off of the MK-7, and I am finally starting to feel better. FINALLY. I feel like a nut job for not figuring out it was the MK-7 sooner. I also am afraid this thing has caused me to start to become hypoglycemic by hurting my liver or pancreas. I changed to one star because the makers of this product are surely either aware of the dangers of the product or are willfully ignorant, and surely they know that the majority of reviewers are taking this way too frequently, yet they give no warning. Do NOT take this more than once a week. If this product hadn't contained alfalfa, I might have figured out sooner that the MK-7 was the culprit. Natto also made me feel way worse the last time I ate it, but I figured that was because of the high iron content of soy. But no, now I'm eating lots of soy again and it doesn't bother me a bit. I haven't itched much all day, so I'm pretty sure the MK-7 was causing that. I'm no longer in need of constant anti-inflammatories, although I still feel like my bones are sensitive as HELL. My chest pain seems to be subsiding, my joints are feeling better, my muscles and veins haven't been throbbing today, and my dizziness/nausea are DEFINITELY decreased. I just hope I haven't done any major irreversible damage in the two months of MK-7 consumption. I will be embarrassed to tell my therapist, doctors, friends, family, and boyfriend that this obscure "miracle vitamin" they've never heard of was the primary thing that was killing me for two weeks and freaking me out rather than iron. I actually recommended MK-7 to two family members and they started taking it the same day I realized this was potentially the culprit. I was too embarrassed to say that this has been the cause of problems, but I did tell them I realized there were some dangers after doing more research and not to take it more than once a week, and told them I'm going to try MK-4 and let them know how it goes. The fact that I recommended it to them is a large part of why I finally figured out it was the MK-7, because I didn't want to recommend something I couldn't really speak for, which made me do more research and gave me doubts. Once every one to two weeks in doses 45mcg is probably the max recommendation anyone should be getting for this. I do NOT know why those foods made me itch before, but not now. Maybe because I ate cheese with most of them. Maybe because they had small amounts of MK-7. Maybe it was the combination of iron and MK-7. I just don't know. I've read that oxidation causes itchiness, so maybe both of them were causing oxidation via excess, for all I know. Not enough is known about MK-7. I think the worse itchiness I experienced was probably in relation to the times I took the MK-7 in pill form, which may or may not be due to the combination of high MK-7 with high iron found in these pills. Brie (which contains 6% DV iron and I think same amount of MK-7 as Gouda) always seemed to cause more itchiness than Gouda (no iron), and I also always ate Brie with bread, which contains iron among other things - but who knows! I will continue to update this review and probably edit it to make it shorter, but for now I'm leaving the whole disgusting thing. ARGH, I hate this salesman mentality wherein people think it's bad salesmanship to actually warn people of the risks of the product unless required by law or unless the business is at risk of lawsuit. I don't want a lawsuit, I just want them to stop making fools of us and helping us to hurt ourselves! Especially when they are marketing a HEALTH product!! Is that too much to ask?!?! My example may be extreme, but it seems like almost everyone who buys this product is destroying their health by taking too much! The fact that there's poor documentation of and awareness of these risks makes it MORE important that the company put a warning on it. Update Nov 12: I thought MK-4 would be better. It wasn't. I've tried other things, including D3 and magnesium. All of these exacerbate my problems. K2 seemed to just deplete my Vitamin D, which I think I'm deficient in. Vitamin D supposedly just depleted my magnesium. Magnesium supposedly depletes my calcium? Calcium supposedly destroys everything without D3 or without enough? Since taking the MK-4 and D3, my memory has gone all downhill, which makes me think I'm deficient in magnesium, but the magnesium so far has just seemed to suck the life out of my bones... I so want to stop all supplements now, but it's like a rabbit hole that's hard to get out of. Someone should've told me to start with magnesium, I guess? It seems like K2 is just the rabbit hole, the one that begins this process of nutrient depletion. I don't know. What I know is that K2 started giving me scary chest pains. It's easier to tell what's going on with MK-4 since it only lasts a few hours in the body. So I can say for sure that it was making things worse. Update Dec 1: Iron may have had a little to do with it, but I'm pretty sure now that the main culprit was some issue between calcium, D3, K2, and possibly other nutrients. I stopped taking all supplements because 3-4 magnesium pills made me feel like I was seriously about to have a heart attack, and gave me other VERY weird symptoms. I felt horrible for three days after that, but then I started feeling much better after 2-3 more days. Clearly the best solution was to get off supplements entirely. After a couple weeks off supplements, my improvement was slowing down so I tried a small D3 supplement and think it probably made me feel slightly worse, but hard to tell. Then 2-3 days later, I took an iron supplement to see what happened... well, that DEFINITELY made me feel super tired and I had to go to sleep and woke up feeling exhausted. So yeah, sick of these supplements. Still believe the K2 was depleting my D3. My body is still pretty out of whack and fragile

We have come to trust NOW brand products in our home. We take Vit. D3 with this product as recommended by my D levels are always great when I get my bloodwork done every six mos. so I know it's working. Thyroid patients are commonly low in D3. This is why I take it. Hubby takes it for joint pain. He says it works for him. I take 1-2. He takes 3-4