Dr. Amy Nett: Ooh, I wouldn’t. I don’t think so. I always have a little bit of reluctance because you never know what we’re going to find in five or 10 years and maybe just a year from now, right? Remember we all used to say “take as much vitamin C as you can,” and then it turns out it is a pro-oxidant at higher doses. If you’re using vitamin K specifically for cardiovascular disease, I think you want to make sure that patients have adequate vitamin D and A on board, but I would still monitor their serum level of vitamin D. I still wouldn’t necessarily go above a serum level of maybe 55 or 60 and similarly vitamin A. I think long term I would have some reluctance. I certainly wouldn’t want to match that high of a dose because if you think about what matching means, you know, vitamin K recommendation for maintenance might be something like 500 mcg, maybe 1 mg, and if you’re doing 30 mg for treatment of cardiovascular disease or osteoporosis, that’s like 30 times higher than the recommended dose. I just wouldn’t want to go anywhere near that much of an increased dose of vitamin A. I would make sure you have adequate levels, and that might just be something like two teaspoons of cod liver oil daily. You could probably even get away with one teaspoon of cod liver oil daily, sun exposure, and also just be aware of timing in terms of when you take those. If someone is taking that much vitamin K, I would probably also think about how you time that. I would have maybe the majority of vitamin K taken with the fattiest meal of the day, so if someone characteristically eats one meal that has the most fat, I would put vitamin K there and also have them take the vitamin D and A there, whether it’s cod liver oil or isolated supplements.
I think Chris Masterjohn, he has a podcast now, and he did one on “ask me anything about fat-soluble vitamins,” and he mentioned the idea of even potentially being so cautious about vitamin A and K timing that you could do some before, some in the middle, and some after the fattiest meal just to mimic how we might get vitamin K in our diets were we to be eating some of these higher vitamin K2 foods. No, I don’t think you need to match the vitamin D and A, but I would think about things such as timing and maybe spacing it over the day, not just doing it in a single bolus dose and making sure you at least have adequate vitamin D and vitamin A, but yeah, I’d be scared to go up that high in vitamin A, but good question because you definitely need to think about all three in synergy.