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S1E9 The world of vitamin D and other supplements with Dr Conor Kerley

Listen to S1E9: The world of vitamin D and other supplements with Dr Conor Kerley

Many experts believe that vitamin D is a key regulator of the incidence and severity of MS, and this is one of the reasons why ensuring sufficient intake of this critical natural resource is one of the pillars of the Overcoming MS (OMS) 7-Step Recovery Program. So, it’s timely that this episode of Living Well with MS picks the topic apart with a guest well-versed in his own right on the topic, Dr. Conor Kerley. 


Episode transcript

Geoff Allix  00:00

Support for the Living Well with MS podcast is provided by Overcoming MS, a global charity registered in the United States, United Kingdom and Australia, whose mission is to educate, support and empower people with MS in evidence based lifestyle and medication choices that can improve their health outcomes. Please visit our website at to learn more about our work and hear directly from people around the world, about the positive impact Overcoming MS has made on their lives. Now on to today’s episode. In today’s episode, we’ll be talking about the world of Vitamin D and other supplements. Joining me today is Dr. Connor Kerley. Connor was diagnosed with Multiple Sclerosis in 2003, at the age of 15. Up to that point, Connor was a healthy athlete and student. Inspired by his own circumstances, Connor went on to receive a bachelor’s degree in Human Nutrition and Dietetics from Trinity College, Dublin in 2010 and a PhD from University College, Dublin in 2016. Connor has worked in diverse research and clinical settings in Ireland and Washington DC. Currently, he is developing an all natural nutrition preparation to deliver key nutrients directly to the brain. Now, Connor is symptom free, relapse free, medication free and still playing several sports, demonstrating the power of lifestyle choices. So Connor, why is Vitamin D important in general to the general population?


Dr Connor Kerley  01:34

Yeah, so Vitamin D, like all vitamins is absolutely essential for humans and originally it was thought to be only really important for bone health. One of the major roles the Vitamin D is to increase our absorption of calcium and we know that calcium is extremely important, for example, for bone health, but we know that Vitamin D has lots of additional roles and we’re finding new applications of Vitamin D all the time. So it turns out there is Vitamin D receptors in every single cell in the body, and you know; within the brain, within the spinal cord, within the breasts and the prostate and why else would it be there except if it had a function and we’re discovering these functions on a daily basis, well, maybe not daily, but on a regular basis. In terms of specific to MS, we know that Vitamin D has a huge role in regulating immune function, so the way I like to explain it to my patients is almost making the immune system smarter, not as strong or working harder, it actually works smarter. So it kind of does more of the right thing.


Geoff Allix  02:35

So we know that people with MS tend to have low Vitamin D levels, but could it be a cause and effect situation? Could it be that MS causes low Vitamin D rather than low Vitamin D causing MS?


Dr Connor Kerley  02:51

Yeah, it’s a great question. I suppose Vitamin D has an added layer of kind of complexity because unlike most vitamins the major source of Vitamin D for almost all humans on the planet is from sun exposure, not directly from food. Whereas most vitamins, or all vitamins really we get mostly from food and so this means that anybody for whatever reason, who doesn’t get a lot of sun, whether it be, because of where they live, or because of their lifestyle, or maybe because their illness prevents them from getting sun, they can have low Vitamin D levels, but of course that’s the disease causing low Vitamin D levels. So a simpler example could be you know if somebody’s bed bound and you know maybe with severe MS or you know, whatever else it is, they are unlikely to be getting a lot of sun and thereby their Vitamin D levels can be low and we’ve seen that almost every disease has been linked to Vitamin D levels, but actually providing Vitamin D supplementation does not provide benefit in many diseases. However MS being a little bit different and being an autoimmune disease associated with a dysregulated immune function, It does actually seem that Vitamin D is particularly important in autoimmune diseases and especially MS. So although it is possible that you know someone with MS and disability may not go outdoors or maybe dressed up and not expose their skin when they do go outdoors, it does seem that Vitamin D is important directly for MS.


Geoff Allix  04:24

For people who’ve got children who obviously got an increased risk of getting MS. Is it worthwhile that they supplement, is there a potential that they could lower their risk of getting MS by supplementing with Vitamin D?


Dr Connor Kerley  04:43

Yeah, it’s a really interesting question again, and there is some really good data showing that Vitamin D, higher Vitamin D levels are protective against MS. So I think this is certainly if somebody you know, if there was a genetic history and somebody’s worried about their children being at risk of MS, It’s certainly worth considering Vitamin D supplementation and at the very least having Vitamin D levels measured. One of the initial studies from Harvard, from probably about 15 years ago at this stage, showed a 40% reduction, which is minimal Vitamin D supplementation in terms of MS risk, so 40% decrease risk of MS, by taking 400 units of Vitamin D, on a daily basis, a Harvard study showed that and lots of studies have kind of shown the same thing, since I suppose, as I say because the major source of Vitamin D is sun exposure and this means that in modern lifestyle when people maybe don’t get as much sun as we would like, and also, you know, I’m here in Ireland, where we don’t get a lot of sun, and that Vitamin D can be certainly a nutrient of concern. But you know, thankfully, it’s easy to measure and it’s also easy to correct and taking that targeted supplementation, which is really quite safe.


Geoff Allix  05:58

And how would you go about measuring your Vitamin D level?


Dr Connor Kerley  06:02

Yeah, so there are two ways to measure Vitamin D in the blood. Turns out one of these is the hormonal form, which we don’t really want to, that’s not really what we want to look for, we want to look for a form called 25 Hydroxyvitamin D and this is often abbreviated as 25OHB and most physicians can measure this very easily, whether it be your primary care physician, or your general practitioner, or your hospital based physician, they can measure this really quite easily and quite cheaply and I would usually recommend getting this checked twice a year for somebody with MS or at risk of MS, maybe once towards the end of summer and once towards the end of winter it will kind of give that person a good handle on, you know, if they’re getting enough Vitamin D, and if not, what strategies they can take.


Geoff Allix  06:51

Is it quite quick to react? So if you took a lot of vitamin, so over the summer, if you had a test in September, it will have reacted to the Vitamin D you’ve got? Is it on a daily basis, weekly, monthly?


Dr Connor Kerley  07:05

Yeah, so I mean, if you took a huge amount of Vitamin D today, you probably could see a fairly significant change in your blood level tomorrow, but generally, we don’t really want to look at daily changes. What’s really fascinating is multiple studies, including some of my own here in Ireland have shown that the highest level of Vitamin D will be in September time, in other words, at the end of summer, and for our colleagues in the southern hemisphere like Australia, that would be the inverse; at the end of March, would be the highest levels at the end of their summer and vice versa, then the lowest levels for in Ireland and the UK and North America would generally be in March time, whereas in Australia, the lowest levels would generally be in September at the end of their summer.


Geoff Allix  07:52

So you do build it up over a period of time?


Dr Connor Kerley  07:55

Absolutely. So Vitamin D is what we call a fat soluble vitamin and this means that we can store it. It turns out that what we call it in science terms, you call it the half life of Vitamin D, in other words, if your level is 100, after about 30 days, that will reduce to about 50. If you don’t get any extra Vitamin D from any source, after another 30 days will generally decrease by another 50%. So in other words, we go from 50 down to 25, and so on and so forth. And this kind of demonstrates that if you have a high level at the end of summer, and that throughout the winter, there will be a store you won’t end up with a deficiency, but you may end up with low levels of Vitamin D which can impact things like your bone health and your immune function.


Geoff Allix  08:40

Okay, and what’s, you mentioned sort of levels, so what would a healthy level of Vitamin D be?


Dr Connor Kerley  08:46

Yeah, so, in general, this can be a little bit controversial because there’s different societies, medical and scientific societies around the world. But generally, in terms of avoiding deficiency we’ll generally look to be above 50 nanomoles per litre. In, places like America, the reference range changes, that will generally be 20 nanograms per milliliter, so there are two different ways to talk about Vitamin D levels, but that’s to avoid deficiency. If we want to look at optimal immune function, we’re probably looking at above 75 nanomoles per litre and in fact, Overcoming MS recommends above 150 nanomoles per litre, and that’s 60 nanograms per milliliter in the US.


Geoff Allix  09:41

And is there an upper limit? Would you say, if you’re 175 do you think well okay, that’s fine. But then if you were 275, would that cause a potential issue? Would you worry about having it too high?


Dr Connor Kerley  09:56

Yeah, absolutely. So I mean Vitamin D is a fat soluble vitamin which basically, you know, for the terms of toxicity means that we can store it in our body and in theory, it can build up over time and be stored in our fat tissues and cause toxicity. In terms of a blood level, we’re probably looking at a level of about 350 nanomoles per litre for Vitamin D toxicity. However, what we need to consider is what is the benefit? And what is the risk of having a high Vitamin D level, like around 250 nanomoles per litre, or 100 nanograms per milliliter in the US, to my mind there is a potential of harm, and there is not a proven benefit. So I wouldn’t advise people to go quite that high, but in around 150 nanomoles as Overcoming MS does seem to be really quite safe.


Geoff Allix  10:51

So I actually tried to keep mine between 150 and 200 and that seems that’s a reasonable amount is it?


Dr Connor Kerley  10:59

Yeah,  I think, you know, in around 100 to 150, is probably a pretty good place to be, and you know we do know from studies looking at populations who live, for example, as hunter gatherers in the original sort of circumstances that their blood levels are generally higher than 100 nanomoles per litre and they certainly don’t have any problems at all and interestingly, their Vitamin D comes solely or mostly from the sun.


Geoff Allix  11:34

And there’s more than one type of Vitamin D. So what what type of Vitamin D should we be taking?


Dr Connor Kerley  11:41

There are, so the main two forms of Vitamin D, are Vitamin D2 also to called Ergocalciferol and Vitamin D3 also called Cholecalciferol. So it turns out the Vitamin D3 is the form of Vitamin D our bodies make when we get sun, and this is also the form of Vitamin D which is an animal based foods like fatty fish; like salmon. It also turns out that Vitamin D2 is the kind of the plant based form which we can find in certain mushrooms and certain supplements. But research has shown that Vitamin D3 is much more effective, both in raising Vitamin D levels, and also in actually having a clinical effect, for example, on the immune system and sort of if a person has a choice, I will always go Vitamin D3 over Vitamin D2.


Geoff Allix  12:31

Okay, and what about getting Vitamin D directly from the sun, are you saying that’s how you get vitamin, you make vitamin D when you get sun exposure? So what about sun exposure as a means of getting Vitamin D?


Dr Connor Kerley  12:44

Yeah, so with my patients, I recommend getting moderate, sensible sun exposure. So what do I mean by moderate and sensible? So really, Vitamin D, would in terms of the sun, we should never burn, or the aim is not to burn to redden our skin and cause skin damage. But certainly, I advise my patients to get some moderate sun and that’s what I practice myself. So there’s there’s a very simple rule and that any listeners can maybe take heed of and it’s basically you want to look at your shadow, If you’re outside in the sun, and it’s sunny, you can see your shadow on the ground, you want your shadow to be the same size as your body or smaller. So in other words, if the sun is quite high in the sky, your shadow will be quite short and this means that you can make Vitamin D. But if your shadow is quite long, this means the sun’s quite low in the sky and it’s not very strong and you’re not going to be able to make Vitamin D. What’s interesting is we generally need to expose, I always say naked skin, but I’m not advising people to walk around naked, but naked skin. So in other words, clothes block the effect of sunlight on Vitamin D production. Similarly, there is some good data showing that sun screen blocks it as well and that’s been a little bit controversial, but it does seem that sunscreen can in fact block Vitamin D production from sunshine. Similarly, being in the shade, being behind glass, all of these factors can certainly influence Vitamin D production from the sun. So for example, if somebody can get out and read a book for 20 minutes and you know if they can go for a walk on the beach or in the park for 20 minutes, and just expose some skin. Again, what I usually advise for my patients is to expose more skin for less time. In other words to go out in shorts and a vest or a swimming suit or whatever for maybe 20 or 30 minutes, as opposed to going out with less skin like just your face and arms showing for maybe an hour or two hours. Because really interestingly, it’s each unit of skin has a capacity to produce Vitamin D and once that unit of skin for example, let’s say your hands, once your hands have made enough Vitamin D, it doesn’t matter if you leave your hands out for one hour or two hours, the Vitamin D is produced. Whereas if you roll up your sleeves, and then exposure arms, your arms can then start producing Vitamin D. So as I say, you want to have a short shadow, and you want to expose more skin for less time. And the final thing of interest for anybody who’s following the Overcoming MS program, is that it does seem that certain foods can help protect the skin from within and these have been mostly things like fruits and vegetables and tea, and things like that and can protect the skin from the inside.


Geoff Allix  15:37

So to protect the skin from sun exposure?


Dr Connor Kerley  15:41

Yeah, from sun damage as such. So we know that, you know, certain nutrients are picked up by the skin, and again from within, and can contribute to healthy skin and protecting the skin against harmful ultraviolet radiation and of course, sun like anything can be abused and can be harmful, but you know, again, I would often say something like water, if we drink, you know, 20 gallons of water, that could be really, really harmful. But nobody says don’t drink water, so again, with sun, we just need to have a little bit of science and not overdo it. But certainly, I think some sun is quite healthy.


Geoff Allix  16:20

So with the fact that suncream probably has an effect in blocking Vitamin D production, does it make sense to go out in the sun, so you’re on holiday, rather than the traditional, if you like, where you put your sun cream on, before you leave your apartment? Many advice actually was to let it soak in sort of 5 or 10 minutes before you go out in the sun at all you’d have you’d be fully covered in factor 50, would you say it makes sense to say go out for 20 minutes and then put some cream on?


Dr Connor Kerley  16:20

Yeah, so unfortunately, this is where it gets really complicated, because you know, someone’s on holiday trying to chill out and enjoy themselves, are they gonna go out for 20 minutes, and then come back in and then put on the sunscreen and then go back out again? That’s the way I would do it and you know, does that always suit each person’s, you know, preferences and so on and their schedule. Unfortunately, there is no easy answer and but you know, what you’ve just mentioned would be a fairly good strategy, but of course, it gets complex in terms of actually doing it. What I would just mentioned is that for someone with kind of light caucasian skin, you know, 20 minutes of sun exposure in a bathing suit can produce about 20,000 units of Vitamin D and that’s really quite a lot, for example, a glass of milk, which is fortified with Vitamin D might contain 100 units. So 100 units in a glass of milk, or 20,000 units from 20 minutes of sun, I know which one I’d rather. So for example, if someone’s on holiday, maybe they can go out in the sun, maybe twice a week with no sunscreen for about 20 minutes and then put the sunscreen on but maybe not have to worry about it the other days, and you know, people generally will will have to think about their own strategy. But your body won’t naturally overproduce, you said once an area of skins, like produced it’s amount, it will stop. But if you said, after 20 minutes, you actually produce 20,000 units, I presume your body wouldn’t actually give you any form of toxicity from having too much? Yep, you’re absolutely right and again, this is this is really interesting, from kind of an evolutionary point of view. So it turns out that It was we mentioned briefly before that, you know, it is possible to get Vitamin D toxicity from inappropriate supplementation, but it’s not possible to get excess Vitamin D from sun exposure. So, you know, being out in the sun all day, everyday may not be very good for your skin, but it’s certainly not going to contribute to your Vitamin D levels going too high.


Geoff Allix  18:57

And when were you saying you you’re in each area of skin will have a maximum amount, when does that get reset? So does it sort of overnight?  In the UK certainly, I don’t if this applies everywhere, but they, traditionally it’s changing somewhat in the last couple of years, but traditionally, we’re happy with quite low levels of Vitamin D, like much, much lower than we’re talking about, and then if you were at this very, very low levels, if you sort of the people with 25 nanomoles per litre, and then they would say oh you should supplement you know, 1000 iu, to try and bring that up, they seem to be very reticent to go with high levels and certainly I mean my neurologist, he’s quite forward thinking was still talking about oh, you should probably supplement 1000 iu a day, and really he finds anything above that extraordinary. When you see, when you hear a lot of people on the OMS protocol on 5,000, or 10,000 iu’s a day. So should we follow the doctor’s advice? I mean, a general protect practitioner, would you say, Okay, well, they seem to know what they’re talking about, I’ve got a level of 25 nanomoles and they’re saying take a 1000 iu’s, is it safe to go off and do our own thing if you like?


Dr Connor Kerley  19:58

It seems to be roughly within about a 24 hour period of time, and roughly about 24 hours. I mean, I would be a little bit cautious of going off and doing your own thing all the time, it is possible to overdo it on Vitamin D. In terms of Vitamin D response to supplements, generally, the lower your level, when you start, the more pronounced the response. So if someone who started 25 nanomoles per litre, and takes 1000 units, and you know, they might quickly go up to 60 or 70 nanomoles per litre, whereas if somebody started out, you know 75 nanomoles per litre on top of taking 1000 units a day, it probably would have little impact. What’s really interesting about Vitamin D is the response seems to be very individualised. So for example, I did a study here in children with asthma and giving them 2000 units per day, these were children not adults, so 2000 units was quite a decent dose and some children’s level went up quite significantly, some children’s level didn’t change, but some children’s levels actually went down. So they were taking 2000 units a day and their level went down and when we measured their level at the start and the end of the study, and the reason I’m telling you that is because you know, everybody’s response can be individualised and that’s why it can be important to keep an eye on your blood level. And, you know, if I was to take 1000 units, today, I might increase by up to 10 nanomols or something like that up to, let’s say, 80, or 90, but somebody else may not increase at all, and somebody else maybe decrease, and so on. That’s kind of the value of, of knowing your blood level.


Geoff Allix  20:38

So you’re saying it’s worth checking every six months. But to start off with until you get to a sort of happy, stable level, would you check, just to see what it is initially, okay, what is after a month of supplementing, maybe, just to try and tailor it, it needs to be personally tailored I take it to, to each individual?


Dr Connor Kerley  22:00

So generally, what I would recommend is maybe getting a check every two to three months, once you start a supplement regimene. There’s very little benefit to be had from measurement to more much more often than that, for example, if somebody was to take 1000 units per day, it might take two to three months for the levels to stabilize. So if you measure it after a month, it’s not really telling you the full response, It’s just telling you where it’s getting, where it’s going to go to, you know, it’s going to be increasing all the time, potentially at least. And so if somebody out there is just starting Vitamin D or has just changed their Vitamin D dose or something like that, I would say stick to a consistent dose on a daily basis, and measured maybe after two to three months.


Geoff Allix  23:08

Okay, and is there anything else we should know about Vitamin D before we move on?


Dr Connor Kerley  23:12

Yep, there is a couple of interesting things I just wanted to point out about Vitamin D. So as i say Vitamin D is fat soluble and that means that it’s best absorbed when you take it with a meal, which contains some some fats. So I know a lot of people on the Overcoming MS program, maybe taking flaxseed oil, or maybe taken some oily fish or maybe eating some seeds and nuts, so just generally having a breakfast, lunch or dinner, including some of these fats, that’s the best time to take Vitamin D. So that’s one kind of interesting thing about Vitamin D. The second thing I just wanted to mention about Vitamin D, was that, as I mentioned at the very start, Vitamin D increases absorption of calcium and generally, you know, a lot of medical practitioners will consider Vitamin D and calcium together. However, if your Vitamin D level is quite high, and if you’re taking quite a lot of Vitamin D, this obviously is going to increase how much calcium you’re absorbing and if you’re having quite a lot of calcium in the form of supplements, this can actually push your calcium level too high. We’re actually aware of some cases where people with MS have been taking high levels of Vitamin D, but also high levels of calcium and this has caused quite a lot of harm. So if anybody out there has taken quite a lot of Vitamin D, I would advise caution, taking high dose calcium supplements specifically, as I say Vitamin D helps you absorb that calcium and if you’re taking a lot of calcium, and you’re gonna absorb it even even better than you would without the Vitamin D, then that can quickly lead to problems with too much calcium and that can be quite problematic. The last thing I just wanted to mention about Vitamin D is it does seem Vtamin D is important and we still have lots of questions that we need answers to about Vitamin D and general health as well as MS health, but it certainly is not a magic pill. So a lot of people say to me; well, I know my Vitamin D levels are high, I take Vitamin D all the time, and I’m still not getting the benefit, I expect. Vitamin D is only one aspect of health, It’s not the be all and end all.


Geoff Allix  25:21

And talking about that, there are other supplements that someone with MS should be taking?


Dr Connor Kerley  25:25

So there is a huge amount of supplements available for all sorts of indications. In general, it’s in the names so a supplement should supplement a healthy diet, if the diet is good enough there should be very little need for supplements. And if the diet is not good enough, the person should try and change their diet before they resort to supplements. However, there are some exceptions, and we’ve just talked about Vitamin D, as I say Vitamin D is very difficult to get from your diet, from your diet alone and that’s why supplements are a very good, very good alternative to eating, you know, maybe two or three portions of fish every single day, of fatty fish like salmon every single day. In terms of supplements in MS, there are some interesting evidence coming out about Biotin. Biotin is actually a B vitamin, a B vitamin like Thiamine, or Folic Acid,. It turns out that some of these studies have used a very high dose of  Thiamine, but what’s interesting about Vitamin B is that, in contrast to Vitamin D, they’re water soluble vitamins, and what that means is you can’t build up a store. So if you take lots of B vitamins, you generally will excrete them in your urine and this is the same for Biotin. So the first thing to say about Biotin is it seems to be very safe and that’s including in the studies with MS, where it seemed to be very well tolerated with very little side effects. One side effect does seem to be that it can interfere with some blood tests, including thyroid tests, which is something to be aware of. But just to put it into context, so the recommended daily allowance for Biotin is about 300 micrograms, and these studies used up to 300 milligrams, which is 1000 times more than the recommended daily allowance.  The food sources of Biotin would be things like seeds, sunflower seeds, and flax seeds, sweet potato, interestingly, is a good source as well as are green vegetables. So, you know, green vegetables seems to be one of the best types of vegetables, things like spinach and broccoli and also salmon, fatty fish, like salmon contain lots of biotin as well. What’s interesting is Biotin and we generally don’t see any deficiency issues with Biotin, because it’s found in so many foods, we only need a very small amount of of Biotin.


Geoff Allix  28:09

Another one, flaxseed oil is encouraged on the OMS protocol, isn’t it?


Dr Connor Kerley  28:14

Yeah, it is. Part of the reason or a lot of the reason is because flaxseed oil contains Omega 3 fatty acids and I know a lot of the listeners will know quite a lot about Omega 3. So Omega 3 is an anti inflammatory fatty acid which we can get we need to get from the diet it’s essential fatty acid we need to get it from the diet and flaxseed oil is quite high in Omega 3 fatty acids. Flax seeds are a good option as well as are walnuts, but flaxseed oil contains a higher concentration of Omega 3 than the whole flaxseed, because obviously the oil is extracted. And and we know that Omega 3 does seem to be of importance when it comes to inflammation, autoimmunity as well. So flaxseed as a source of Omega Three seems to be good option and quite interestingly, most people do not get enough Omega Three, including those with MS.


Geoff Allix  29:20

Okay, so that’s definitely worth adding in. Another one that came up relatively recently was Vitamin K2 and how that might have some connection with Vtamin D as well and whether it’s worth supplementing with K2 as well?


Dr Connor Kerley  29:36

So Vitamin K is very, very interesting. So it’s a little bit similar to Vitamin D. It turns out that Vitamin K is a fat soluble vitamin, and again, not too dissimilar to Vitamin D. There are two main forms of Vitamin K, there’s Vitamin K1 and Vitamin K2, and we know that Vitamin K1 is really important for helping the blood to clot, and if any of your listeners are on medications like Warfarin, they will know all about Vitamin K, and it’s important for blood clotting, however Vitamin K2 does seem to have additional roles in the immune system for bone health and so on. It turns out to be get lots of Vitamin K1 from green vegetables and sources such as lentils, some fruits as well, whereas Vitamin K2 is a lot rarer in the diet. It’s made by bacteria, and it’s found in some fermented foods and some animal foods. So an example of a fermented plant food will be something like Natto, which is a fermented soy product. Also, things like sauerkraut, tempeh, and kombucha are a good source of Vitamin K2. But yet, you mentioned Vitamin K2 working together with Vitamin D, it turns out that many vitamins work together really all over the body, we call this kind of nutrient synergy and this is part of the problem with taking an individual supplement that, you know, if you say, you know, let’s just pick randomly like you say Vitamin C is good, well just taking a Vitamin C supplement is not the same as eating foods rich in Vitamin C, but also containing a lot of nutrients which help VItamin C work better. And just to bring it back to MS, there has been some recent data showing that Vitamin K levels are lower in MS than those who don’t have MS, but we’re not sure yet of the effects of increasing Vitamin K2 in MS. So it’s definitely an area to keep an eye on and for the moment what I would advise is certainly eating lots of green vegetables for Vitamin K, but also for lots of other reasons as well.


Geoff Allix  31:47

And you mentioned sort of the vitamins interacting with each other. So is it better to take a multivitamin tablet rather than taking specific vitamins?


Dr Connor Kerley  31:58

Yeah, so it’s another good question. I’m in general, I don’t really advise multivitamins. This is because there are some nutrients we know can be harmful in supplementation form and these nutrients might include something like Beta Carotene and if I’ve got time, I’ll very quickly tell a little bit of the backstory. So Beta carotene is the precursor to Vitamin A and it’s found in orange, and on brightly coloured fruits and vegetables, like carrots and sweet potato, and so on. So in the past, it was noted that those who had lots of Beta Carotene in their blood actually had a lower risk of lung cancer. So what scientists did was to find people at high risk of lung cancer, for example, people who smoke and they gave some people Beta Carotene supplements and some a placebo. And they actually found that those who took the Beta Carotene had a much higher risk of cancer and heart disease than those who took the placebo. And that’s been shown several times with Beta Carotene, and with other isolated nutrients. And so I don’t recommend a blanket multivitamin for most people, I recommend a good diet, such as recommended by Overcoming MS and then targeted supplementation of things like Vitamin D. You know, things like flaxseed oil, potentially have a role as well, as well as maybe thinking about Vitamin K2, and things like that. But I don’t think a bit multivitamin is the best strategy.


Geoff Allix  33:26

And who should be taking Vitamin B 12? That’s another one that gets mentioned quite a lot.


Dr Connor Kerley  33:30

Yeah, so Vitamin B 12. It is really, really very interesting. So the first thing to say about Vitamin B 12, is quite a lot of people following the Overcoming MS protocol, decide to forego all animal products, including fatty fish. Vitamin B 12 the only reliable sources in the diet; are animal foods. So anybody who’s following a vegetarian, vegan, or even a heavily plant based diet needs to be aware of Vitamin B 12, and ensure that they either take it on a daily basis in their diet or a supplement. Quite interestingly, in my clinical experience, lots of people who eat lots of animal products still have issues with Vitamin B 12 and that’s because it’s quite difficult to absorb. So if anybody has any issues with their tummy, or is on certain medications, for example, acid medications, this kind of factor Vitamin B 12 absorption. Luckily, it’s very easy to measure Vitamin B 12 and also luckily we only need a very, very small dose. We also know the Vitamin B 12 is really, really important for the central nervous system, including the brain and the spinal cord and hence it’s important for MS. So if anybody is concerned at all, or maybe as I say follows a plant based diet, it’s worth having your Vitamin B 12 level checked. And the final thing to say about Vitamin B 12 is because we need such a small amount we have a store in our bodies and within our liver which can last for about three years, so really if you get checked on your level is okay, I maybe would check it once a year, or once every 18 months.


Geoff Allix  35:05

Okay, and we’ve talked quite a lot about vitamins. What about minerals as well? Is there any minerals that we should be worried about or should consider supplementing?


Dr Connor Kerley  35:13

So minerals sometimes take a backseat to vitamins but minerals are obviously really important too. So minerals including things like calcium, are really important for bone health for heart health as well. Also things like potassium are really important for our blood pressure and for our nerves. But one which seems quite interesting for MS is magnesium. So it turns out magnesium is really important for a huge amount of reactions in the human body, but luckily, we can get it from food and this is what I would recommend. So really good sources of magnesium in the diet include things like nuts, green vegetables, and also lagumes and whole grains. And these are the backbones of a plant based diet, such as Overcoming MS recommends. So the amount of magnesium we need on a daily basis is about 300 to 400 milligrams depending on whether we’re male or female, and what age we are. But it turns out that the serving of any of these foods from nuts, green vegetables, beans or whole grains, even including good old fashioned potatoes, they probably provide about 80 milligrams, so you need about three to four portions, minimum of nuts or greens or beans or whole grains. And generally most people on the Overcoming MS program should be able to meet that target, so three to four portions there should get all the magnesium you need.


Geoff Allix  36:35

So largely, we’re pretty much covering our vitamin and mineral requirements apart from Vitamin D. But if we’re following the OMS diet, we’ve pretty much got everything else covered?


Dr Connor Kerley  36:49

Yeah, so it’s still a good idea to have an idea of what nutrients you might be short on, and what sort of foods contain those. But in general, you know, I just say a well planned diet should should provide all nutrients, one exception being Vitamin D, for example. Another nutrient which is coming out and quite interesting results, specific to MS is Vitamin A. Again, Vitamin A like Vitamin D is fat soluble and we can get in sources such as fatty fish like salmon, but we can also as I managed to get the precursor called Beta carotene in lots of plant foods, like carrots, like sweet potatoes, like mangos, and your green vegetables again, and it turns out these foods contains a huge amount of Vitamin A, or its precursor Beta carotene. So as long as we’re consuming those on a regular basis, we won’t have an issue with Vitamin A and again, I would recommend getting it from plant sources as opposed to getting it from supplements.


Geoff Allix  37:49

Is there any sort of future or current research into supplements there anything that could be changing?


Dr Connor Kerley  37:55

So I think the whole Biotin area is definitely something interesting to look out for, especially because some of the research done on Biotin, specifically to MS has looked at Primary Progressive MS, which is a an area which is certainly lacking. In terms of supplements and MS it’s certainly a really, really interesting area, specific nutrients, specific combinations and we know that for example in MS, things like inflammation and immune system are certainly affected and we know that not lots of nutrients have effects here. So part of what I’ve been working on, what my research team here in Dublin is looking at nutrients which can get into the brain and very briefly, we have a barrier within our body which stops most things from getting in or outside of the brain. This means though, that beneficial nutrients that we get from lets say an apple will very rarely reach the brain. But there are some nutrients which can reach the brain but they’re not found in a lot of foods, and they’re generally not foods we would consume regularly, like on a daily basis. These nutrients would have an anti inflammatory and antioxidant effect within the brain, assuming they can get into the brain. So our research team have been formulating a whole food product which can deliver these nutrients and then the next step would be to see does it actually get into the brain? And then does it have a beneficial effect? So although it’s still in the early stages of its planning, this is a really exciting area, a really exciting time for us on our research team, and certainly something I would be delighted to keep in touch about.


Geoff Allix  39:32

Okay, so it’s not just a static thing, it is actually a moving area of research as well?


Dr Connor Kerley  39:38

Absolutely. Science in general, is never static, but specifically when it comes to food and MS there was a huge amount that we know but there’s a huge amount we don’t know and there’s a huge amount going on to try and figure out things that we don’t know.


Geoff Allix  39:54

Okay, thank you very much for that. I think with that we’ll wrap up and that was very interesting information I think for everyone who’s is following the OMS diet or is considering healthier lifestyle.


Dr Connor Kerley  40:07

Great and thank you for your time.


Geoff Allix  40:12

With that, I would like to thank you all for listening to this episode of Living Well with MS. Remember, there is a wealth of information at, including show notes and an archive of all Living Well with MS episodes. Once again, that’s There you could also find OMS friendly recipes and exercise tips, connect with other OMSers in your local area through our OMS Circles program, and learn about the latest research going on in the MS world generally, and related to OMS specifically. I encourage you to register on the site and stay informed about the latest news and updates. I also encourage you to subscribe to this podcast, so you never miss an episode and please feel free to share it with others who might find it of value. Let us know what you think about the podcast by leaving a review and if you have ideas for future episodes, we’d love to hear from you. So please contact us via our website Thanks again for listening, and for joining me on this journey to Overcoming MS and Living Well with Multiple Sclerosis. I’m Geoff Allix and I’ll see you next time.


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Dr Conor Kerley's bio:

Conor was diagnosed with MS at the age of 15 and fully expected to be forced to curtail his active lifestyle. He was surprised at the lack of focus on diet and lifestyle in his medical consultations, so he undertook his own research, eventually finding OMS and making the necessary adjustments to his diet and lifestyle that have kept him active, symptom-free and relapse-free to this day. Inspired by his experiences, he went on to study human nutrition and dietetics, and received his PhD from University College Dublin in 2016.