Wednesday, July 4, 2018

MK4 vs. MK7 K2 Self-Experiment

N=1 Science: The Great K2 Debate

By Lomeloth - Own work, CC BY-SA 3.0 

Many years ago – 8?? I'm not really sure – I started supplementing vitamin K2. I began taking it for reasons of heart-health. However, after I started supplementing it I discovered it had a noticeable and almost immediate effect on my oral health. Suddenly my teeth were glossy and smooth. They felt like after a professional cleaning. 'Morning breath' was also very noticeably lessened, absent even. After a year or so I even stopped brushing my teeth in the morning, seeing no point to it – I don't eat breakfast except on weekends. I do brush afterwards on days I eat breakfast. I also brush every evening immediately before bed using a Philips Sonicare toothbrush.

I also noticed that if I ever went much beyond a week or so without supplementing K2 I'd be reminded by a combination of my teeth no longer feeling smooth and glossy and a return of “morning breath.” It wasn't bad morning breath by any means, more of a not fresh-in-the-mouth feeling, but compared to nothing at all, which is to say having my mouth feel pretty much the same first thing in the morning as anytime else during the day, it was an unmistakeable difference.

I was aware of what I call the great MK4 vs. MK7 debate since first encountering K2. My first choice of K2 supplement was a “Super-K,” which had K1 and both forms of K2. After discovering the effect K2 had on my teeth, I decided I'd go with Thorne's MK4 oil. It was a bit more expensive as MK4 sources go, but since the vitamin was having an undeniable positive effect on at least one aspect of my health, it seemed money well spent. Also, MK4 being the dairy form, and obviously we humans being mammals, I figured that MK4 was likely to be the most bio-active.

Back in January or February PD Mangan shared a few links from some Japanese studies that indicated MK7 was a superior form of K2. I read through them carefully and found their methods fair and their conclusions compelling. All the obvious criticisms and confounds I could think of were addressed. It made me wonder if I had been wrong about my choice of MK4.

Yet, there was no denying the impact MK4 had on my teeth. Also, no one that I had read, these latest studies included, had make a connection between K2 and oral health. Maybe MK4 was unique in its oral-health effect? Maybe I was better off with MK4 for that reason alone?

Well, as fate had it, a few weeks after Dennis' post I found myself out of K2. This gave me an idea: this time I'd order MK7, wait for the plaque & morning breath to return, then resume supplementing with MK7. I would test how my oral health responded to MK7.

I ended up going a solid four weeks without taking any vitamin K2 supplement. About three weeks in I remember waking up with some bad morning breath and again the next day. I decided I'd give it a few extra days to see just how significant the morning breath would get, and if plaque would become a noticeable issue. As it turned out, those two days of “morning breath” were outliers. I don't think I ate anything unusual the evenings days prior, but perhaps I had. After a whole extra week without K2 supplement, I never had noticeably bad morning breath again. Nor did my teeth ever develop the overtly noticeable plaque that I recalled in previous instances of going over a week without supplementing. Maybe all the years of supplementing had built-up a reserve of K2, or at least whatever K2 does, in my system?

After the week of waiting following the original morning breath incidents and my teeth not getting any more appreciably built-up with plaque, I got bored of waiting and decided I'd break my K2 “fast” by taking two 100 mcg MK7 capsules. (My standard MK4 dose was ~400 mcg, taken twice a week. I have always diluted the Thorne MK4 oil with vitamin D oil and olive oil, since mg-level doses of K2 seem far beyond what anyone could possibly get from diet alone so I have been mindful about over-dosing.)

The next morning my mouth felt about like it always did the last few weeks. Through the day my teeth maybe felt like they were smoother and cleaner, but it certainly wasn't an overwhelming sensation. It definitely was not so strong that I could feel absolutely certain it was not psychosomatic. That evening I took another pair of 100 mcg MK7 capsules. The next morning my mouth again felt about like it always did. However, as the day went on I could definitely tell a difference in my teeth. After my morning coffee with ½ & ½ they felt noticeably smooth. Not freshly-brushed smooth, but smoother than they had been any time in the week prior. It was a similar situation after lunch and on my commute home from work. Whereas I had grown accustomed to them being a little “fuzzy” after meals and at the end of the day, that day, for the first time in some weeks they were definitely smooth as I ran my tongue across them, particularly the canines and pre-molars. “Fuzzy” is probably too strong a word for it. It is really what I considered normal before I'd started supplementing K2. There is a baseline level of plaque that I assume is normal and no one even thinks about it. In contrast, there's an atypically-clean level that, outside of professional cleaning or K2 supplement, at least for myself, I'd never experienced. That is now my new normal, but I'm not sure how one would describe the old normal.

After the two-in-a-row I skipped three days and took one 100 mcg MK7 capsule. At that point I could definitely say that, yes, MK7 was having a similar effect as MK4. Since then I've had two more weeks of taking 100 mcg MK7 twice a week and my teeth are smooth through the day just as they normally were taking the MK4. They are absolutely glossy feeling after brushing (again, I use a Philips Sonicare, which admittedly helps significantly compared to a manual toothbrush), and no noticeable morning breath. Success: MK4 and MK7 both mobilize one's own body in whatever unknown fashion to fight plaque. (In my opinion this is more strong support for the blood-bacteria source of aging and heart disease that Mangan writes about often.)

There's more... soon after I'd ordered a re-stock of my vitamin K2, I decided I should get my parents to start taking some dietary supplements (they are in their mid-60's and retired last year). At the least, I wanted them taking the ones I call the “Big-5.” I ordered: magnesium, vitamin D, vitamin K2, Omega-3, NAC, and zinc. OK, “Big-5” plus 1. I recommended that they take one, 100 mcg K2-MK7 capsule twice a week. After my own experiment, it occurred to me I could do a real, blinded trial on them. At that point, they had been taking K2 for less than two weeks, not multiple years like I had. Plus they had been taking a smaller dose. It seemed doubtful they would have started experiencing any oral-health effects yet. If my experiment with MK7 was valid, then with a bigger dose, they too should experience an immediate and unmistakeable change in their oral health.

I called them up, and without being specific said they should take 2 capsules of the K2-MK7 for each of the next three days and let me know if they noticed any differences in anything health related. Ever the coy one, and wanting to be careful not to bias them I said, “It could be physical, mental, or even nothing at all. Maybe I'm prepping you for something else later. :)” The next week I called them back and asked how it went. My mom said she got really light-headed, as in had to sit down and stop working on dinner, light-headed soon after taking the double-dose of K2 caps on the first day. She hadn't taken any K2 since. My dad didn't take any at all because of her reaction. Well, so much for that experiment. It was a bust.

After some explanation that no, I wasn't trying to kill anyone; that I had taken exactly the same amount myself, more than once; that I had never, ever read or come across anyone having an acute reaction of any kind to vitamin K2 – hey, it's just a vitamin – I said I meant to caution her to back-off her blood pressure medicine now that she was taking magnesium and Omega-3, and maybe the NAC could have an effect on it too. However, K2 was not on my radar of something to watch for with regard to blood pressure. At that my mom mentioned she thinks she might have taken her blood pressure medicine at the same time as the K2. Interestingly, she then added that she had actually started taking half-pills a few months back, after they'd started going to a gym regularly, and that more recently she had almost stopped taking them completely, especially after starting with all the supplements I had sent to them. After joining the gym she also bought a blood pressure cuff to track her blood pressure and it had dropped completely back into the normal range since starting the supplements. Well, for whatever reason, that day she took a full blood pressure pill and the pair of K2 capsules. She couldn't remember whether she took them all together or separated by some hours. Maybe the reaction was entirely from the blood pressure pill, or maybe it was an interaction of the two at the same time.

I gave away that I was testing to see if they would notice a difference in the plaque on their teeth from the K2. She then said, “Oh yeah, you know that tartar you get on the back-side of your front teeth? That started breaking off on Sunday. I thought, wow, that's weird, maybe I'm due for the dentist.” (Her double-dose of K2 was taken on Saturday.) I replied, “Yeah, I get that all the time too. I usually just chip it off with a finger nail every so often when it feels a little built-up.” Funnily enough, I never thought that might be from the K2 as well. And so there it was: after two weeks of 100 mcg twice a week, and 200 mcg in one day, the next day calculus started spontaneously breaking off of her enamel.

And there's still more... about 4 weeks after all that I went to the twice-a-year blood drive that our church has. I've had blood pressure in the 130/70 range for around the last 4 or 5 years that I've been donating blood. This time the nurse had great difficulty measuring my blood pressure and when she finally did measure it, she said it was at the bare minimum to donate. She was a little bit rude, and I couldn't hear her well when she told me what my blood pressure was. I think she said it was 100/50. A quick web search seems to indicate the Red Cross requires at least 80/50. Maybe there is something to this K2 and blood pressure thing?

While I have established, at least to my own satisfaction, that K2 has a marked, positive impact on oral health, and both MK4 and MK7 are efficacious in this regard, the question of MK4 vs MK7 is still an open one in my mind; as is the optimal dose.

The typical recommended dose of MK7 is an order of magnitude less than MK4. However, that could be a cost factor more than anything justified by research. In my own experiment, it did take about an equal amount of MK7 to get the immediate plaque-fighting effects that I experience with MK4. Then again, I wasn't remotely rigorous in trying to determine a minimal effective dose. If it takes a commiserate amount of MK7 to get the results seen with of MK4, then clearly MK4 is the winner, as it is so much cheaper. On the other hand, this would fly in the face of all the research showing MK7's superior serum half-life and the research Mangan found which launched me on this experiment in the first place.

Another issue to be cognizant of is that a lot of vitamins and supplements follow a U-shaped response curve – too much is just as detrimental as too little. Before completely deciding on one form of K2 over another, I'd like to see a more complete explanation for how it works and what it is doing in our body, along with a suggested optimal dose. For now, MK4 feels inherently safer as it is from dairy. With MK7, when you look at where it comes from, it's metabolic half-life in vivo, and the amounts typically supplemented, it is almost an altogether different vitamin from MK4. My inclination for now is to stay with MK4 as my primary source of K2, take MK7 once a week as back-up insurance, and continue to keep my eye out for additional research.

If you've gotten this far (2300 words for anyone counting), thanks for staying with me to the end. I reckon you've found it interesting. Beyond sharing with people the advantage of K2 on oral health, what I'd really like and hope to accomplish with writing and sharing this post is to get researchers interested in investigating the K2-dental connection. Who knows, maybe it will even lead to discoveries on the blood-bacteria front.

All my best,
Allan Folz


  1. Once one understands the role of K2 in human physiology, I'd presume that they would naturally understand the benefit that it would confer to teeth. Seems like a "no-brainer."

  2. Following up, I would also maintain that the vitamin itself doesn't have anti-microbial properties (directly anyhow) so much as it enables for more efficient and comprehensive enamel refortification. The "fuzziness" that you have noticed (I have as well), might just be the acidic breakdown of enamel before remineralization. So, it stands to reason that the K2 would ameliorate such a process with relative expedition.

    1. I've not come across any comprehensive description of K2 in human physiology. The only thing I've seen is a hand-wavy refrain, "it moves calcium from soft-tissue, where it doesn't belong, to hard-tissue, where it does."

      The reason I've been skeptical of that refrain is the effect on my teeth and breath is virtually overnight.

      I won't rule-out enamel fortification. However, a physically noticeable effect in less than 8 hours seems incredibly fast for laying down enamel, nor does it account for the breath aspect.

  3. I thought maybe saliva might be an avenue of more immediate change and searched pubmed. Here's one hypothesis: