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Ep66 – The Micronutrients Series: Fat Soluble Vitamins Part 4 (Vitamin K)

Updated: Oct 27, 2023


Hello, you are listening to Katy Bradbury, registered nurse and nutritional therapist. Today’s podcast episode is called The Micronutrients Series, Fat Soluble Vitamins Part 4.


So Hello, good evening, or at least it’s evening, as I’m recording this on a Sunday night as ever here in the UK. I am continuing the talk this week and I’ve been shining over the last three episodes, the light, I’ve been shining the light on a few of the micronutrients. So I’ve been starting with vitamins as they relate to fertility, so been giving a little bit of background, what they found in various facts about them and the things that can impact the status of those vitamins. Now, you may hear, especially if you’re a regular listener, that my voice sounds a bit strange today; I do have a bit of a cold going on. I wondered whether it might be COVID. Actually, I did a COVID test yesterday. Here in the UK, at the moment, COVID is definitely on the rise again. I think it’s about one in 40 people have it; we’ve got a variant of Omicron going around that it’s like superduper transmissible. So loads and loads of people are getting it or getting it again at the moment. But I didn’t actually test positive, so I think it might just be a run-of-the-mill cold. But in any case, I am grateful for your sake as well as mine that today is going to be a relatively short episode because vitamin K, which is the final vitamin in the fat soluble group of vitamins, which covers the A, D, E and K group of vitamins that I’ve already spoken about. So vitamin K, there’s not a huge amount to say about vitamin K. That doesn’t mean it’s not really important. It is important, and I will run through some of the reasons for that today. But it’s not one that I have to go into a huge amount of detail about.


So I have already covered in the last three episodes some information about fat soluble vitamins, genuinely the things that can impact the absorption of fat soluble vitamins. So do go back and listen to those episodes if you haven’t already. If you are a new listener to the show, then perhaps today might not be the best episode to start with. Welcome if you are a new listener. I’m really, really glad to have you here, but starting with a spotlight on vitamin K perhaps isn’t the best introduction to me and to my podcast. So do go back and have a listen to perhaps something that is a little bit more relevant to where you’re at on your fertility journey. There are plenty of episodes to choose from. I think we’re on episode number, oh gosh, 65, 66 now, so there’s lots of stuff. I’m sure you’ll find something that’s pertinent to you and your situation, and then once you’ve gone and listened to some previous episodes and you’re familiar with me and the way I talk and the way I operate, then you know, come to you come back and listen to these this micronutrient mini-series that I’m doing because it is important. I’m just going to pause to do a cheeky sneeze.


Hello, I just gulped down a cup of steaming hot lemon and ginger tea before I started recording the episode in the hopes that it might help my voice of it, but I don’t think it has, so I will spare you having to listen to me for too long because people normally say I’ve got a soothing voice, but I think today I sound more like a, I don’t know a crocodile.


So vitamin K. So really, there are two main things that we associate with vitamin K, and you might listen to these two things and think this has got nothing to do with fertility. Why am I even bothering? But the truth is Vitamin K is an important nutrient for fertility, just as every single vitamin is important for fertility. The reason for that is because vitamins, by their very nature, are essential micronutrients, and an essential micronutrient means that we do not produce enough of that nutrient within our own bodies without any help from an external setting, so we need to get it externally in order to actually get enough of it.


So, with that in mind with that principle in mind, every single micronutrient that I talk about here, every single vitamin that I speak about in this mini-series, is essential. It’s really important for the general functioning of our body and, thus, fertility.


So the main thing that we think about when we think about vitamin K, and you may be aware of this already, is clotting. So vitamin K helps our blood to clot, and we often think about blood clotting as being a bad thing. So blood clots are often thought of as a negative thing. If you’re listening to this for fertility, which you probably are, then you might think of blood clots in terms of your menstrual cycle in getting lots of clotting. So you might think, Oh, actually, I already get a clot. So I don’t want any more of those things. Or you might be thinking about it in terms of cardiovascular disease and thinking about how blood clotting is a risk factor. And that’s absolutely right. It is a risk factor for serious life-threatening diseases. But it’s also life-saving. So just like everything, if you’ve listened to me for quite a while now, then you probably have caught the gist of that. Just because too much of one thing is bad doesn’t mean that too little of it is good. It has to be somewhere in the middle. So blood clotting, what would happen if our blood didn’t clot, and we got a paper cut, for example, or we nicked ourselves shaving, then our blood might not have the clotting factors, it needs to actually stop that bleed. And so we could, you know, we could end up bleeding out for something really simple, like having a cut. So in that respect, blood clotting is there for a reason. We need our blood to clot in those situations. So blood clotting is really important. And you may be aware of the role of vitamin K in newborn infants as well. So if you’re listening to this podcast, and you are pregnant already, or you know you’ve been working with me, and you’re pregnant, or you’ve had a child already, and you’ve got secondary infertility, then you may well be aware that most infants, well all infants really in the UK, are offered a vitamin K injection at birth, or a Vitamin K oral solution at birth. And the reason for that is because a small percentage of, it’s a public health drive, so a small percentage of babies are thought to have depleted stores of vitamin K. And so as a prophylactic measure is a preventative measure to stop them from or to help prevent those small percentage of babies from having a haemorrhage or being at risk of having a haemorrhage, then the Vitamin K is offered, so it’s really quite a potent medication.


Now, really important to note here the vitamin K because of this, this link with blood clotting, is a vitamin that is that does have interactions with medications and potentially supplements as well. So, for example, lots of people that I work with are taking fish oils, and fish oils are a natural anticoagulant, which means it’s a blood thinner. Lots of people, not many of my clients, but lots of people in the UK, in the United States, and in the western world, are on anticoagulant blood-thinning medications. So if that is you, please bear in mind that there can be interactions here, and please always speak to your health care provider if you’re concerned about any of this. Always be sure before you supplement with any, even over-the-counter, supplements. Please always make sure that they are safe and suitable for you. So really important for blood clotting. But just in that respect, really important for foetal development as well. So we want our blood flow to be as normalised as possible during pregnancy because there is one way in, one way out in terms of via the placenta and how we actually how our blood supply reaches our unborn child during pregnancy. And so really important during pregnancy and foetal development that our blood is as normalised as possible in terms of how it’s made up in terms of its constitution.


o the blood clotting is is the main thing that we think of with vitamin K, and the other thing is bone health. And bone health, again, you might be thinking, what has bone health got to do with me? Well, first of all, bone health, again, has got a lot to do with a growing foetus, right. So when you’re growing a baby, when you’re growing a baby from scratch, you’re growing bones from scratch. So we need to make sure that there are enough of all of the nutrients that are helpful for bone health and bone development. Vitamin K is one of those. So certainly, although vitamin K might not directly be associated with egg health and sperm health and all of those other things, the repercussions for newborn babies for foetal development are significant. So we want to be thinking about this stuff now and wanting to be making sure that we are getting an adequate intake of all of these essential nutrients.


So involved in bone support, vitamin K is linked to our bone mineral density. So lots of people get that done as a reading. They get their bone mineral density measured. And whilst it’s true that people, particularly women in their later years, are more susceptible to lower bone mineral density and therefore at higher risk for breaks, fractures, etc. There are certain people in the pre-menopausal years who are also at risk of frequent fractures and bone breaks, etc. So vitamin K may be worth thinking about in those situations.


The other thing, of course, that we linked to bone mineral density is that it tends to deplete in the postmenopausal years and because it links in with our Hormonal Health, right. So lots of people who struggle with infertility struggle because they have suffered from POI, so premature ovarian insufficiency, or anyone who has been told that they are at risk of going into menopause early. This is certainly something to be thinking about just in terms of your long-term health. So definitely something to consider, as I say no direct links to fertility as such, but plenty of things around foetal development and general health.


Now, the final thing I want to say about Vitamin K is that, before I talk about the different sources and how we actually get it, is that it can also be linked to our vitamin D status. So vitamin K is thought to help vitamin D to absorb. Now, if you actually look into the mechanisms of this, it is really, really super-duper complicated. And it’s not in the same way that, for example, vitamin D helps to absorb calcium. Although it is in a similar thread to that, it is a lot more complicated. However, some people do choose to have a vitamin D supplement with a K2 supplement alongside it to help the absorption. So oftentimes, if you’re taking a vitamin D supplement, some people may look at the bottle and say, oh right, yeah, it is. It’s often labelled as like D3 K2. So vitamin D3 and Vitamin K2 that is the typical kind of presentation. Now I’m not going to tell you whether that’s right or wrong because, as you know, as one of my listeners, I do not give supplement advice on the podcast. It would not be safe for me to do so. So I’m just advising you have what is out there.


So, where do we actually find vitamin K? Well, actually, really, really easy to remember. And it’s kale. So vitamin K we can often think of as Vitamin Kale because by far the densest concentration of vitamin K in food form is found in kale. So a cup of kale has over a gramme of vitamin K in it.


But there are lots and lots of rich sources of vitamin K out there as well. So all of your dark green leafy vegetables are fantastic for vitamin K. So your spinach, mustard greens, collard greens, beet greens, Swiss chard, all of those. And then things like Brussel sprouts, broccoli, and parsley, are all really good forms of vitamin K. Even lettuce like romaine lettuce, asparagus, cabbage, bok choy, celery, basil, so just really thinking of those lovely green vegetables in the plant world, but also things like green beans, cauliflower, even to some extent cucumber, tomatoes, green peas, blueberries, so all of those foods have got some vitamin K in them. Also, things like grapes, carrots, squash, and chillies. So lots of different foods do contain some vitamin K, even things like aubergines, plums, melons, peppers, cranberries, and pears. So lots of sources out there.


Now worth understanding that there are three different forms of vitamin K. There is, so I just mentioned before the supplement that might contain K2. Most of the sources that I just recommended are sources of vitamin K1 and K1. Now can I remember what K1 stands for? So K1 is, they’ve all got like really long and complicated names, and I can’t remember what K1 stands for, which is why I’m just stalling while I look up the name. Where are we, vitamin K? I’ve actually got some of my old nutrition college notes up here. I was inspired last week when I spoke about vitamin E, and I found, if you listened to the episode last week, you remember that I found one of my old college essays on vitamin K. And so I just remembered that I have all of these outcome old notes for most studies. And I thought I’d bring that up today. Anyway, that stalling has helped me find what I was looking for, so and to be honest, you really don’t need to know this. I’m just showing off, but phylloquinone is Vitamin K1, and that is the normal dietary source, which is found in most leafy vegetables, and other plant foods that I’ve listed. Menaquinones is K2. Now very, very interesting here, which because we often think about food being our primary sources of certain nutrients, with the exception, of course, being vitamin D, which I spoke about a couple of episodes ago, which we tend to synthesise ourselves from sunlight. But vitamin K2 so menaquinones, I’d love to know if you already know this, because it’s actually really fascinating, are actually synthesised largely not from the foods we eat, not from the sunlight that we absorb for our skin, but through our gut bacteria. So it’s actually, so I always talk about the gut, and I did a mini-series just like this one within the podcast a couple of months ago now about digestion. And so if you go back and listen to that mini-series, if you haven’t already, because really, really important stuff in there and digestive health and gastrointestinal health is superduper important for fertility. And if you don’t know that already, then please do go back and listen because it’s integral to the way that I operate with any of my clients; we always look at the gut first. Now, what is really interesting is that K2 is synthesised by bacteria in our large intestine. So again, it’s a testament to us needing to have the right kind of bacteria in our gut needed to have that great gut health in order for our gut microbiome to do what it does best and produce some of those compounds and other things, I had a mind blank there, other things that our body really needs to reduce inflammation, for homeostasis to take place, for normal hormone production to take place and for inflammation to be reduced. So it’s really important to get that gut health in gear. There is a k3 as well. Mostly the K3 is synthetic, and that would then be metabolised in the body to that K1 form.


So really interesting stuff. I think that there’s a bit of a gap there, there could be more evidence, or there could be more research done on Vitamin K. To be honest, there is some out there, but I would really love there to be a bit more about how the menaquinones, the vitamin K3 that is synthesised by a gut microbiome. I’d love to see a bit more research into how that is actually uptaken and how that is actually used by the body because it’s just fascinating stuff. But if you’re not a geek like me, you might not be as fascinated by that. But hopefully, you’ve at least found it interesting to hear that that’s where some of our vitamin K2 comes from.


So that’s it for me today. Thank you for putting up with my croaky voice if you’ve listened to it all the way to the end. I did want to send a little reminder as well. If you are a regular listener to the podcast, or if you’ve listened to this episode and enjoyed it, please do go and give me a star rating on whichever platform you listen to. Please do give me a review of the show. Let me know what you think. And I will be back to speak to you again next week. Take care

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