Heather: Vitamin D is essential for us to be healthy, and we could obtain from sunlight,
certain food sources, and supplements. I want to know how much of that can we get from each
of those three. How much sunlight do we need, how many hours for example? How many mushrooms
would we maybe need to eat? Do supplements really work? It's quite a debated topic,
so today I am going to be speaking to a nutritionist to answer all the questions
around this very vital vitamin. [music]
I am excited to find out more about vitamin D. I know as humans that we can't survive without it.
If you have a deficiency as a child, it could lead to something called rickets.
Although, thankfully, extreme deficiencies like that are very rare in the modern world.
Although, we could be lacking vitamin D without even knowing it. As athletes,
any small imbalances are always exacerbated due to the stress that we put on our bodies.
Today, it is the athlete perspective that I'm looking at this problem with, and it all arose
from a conversation I had with Mark when he was just talking about, in the winter months
he religiously takes vitamin D as a supplement and really finds that it makes such a difference to
him. Whereas, I, on the other hand, have only taken supplements through one winter and that
was as a result of the nutritionist insisting we took it and it was just easier to go along with
it rather than argue. I want to find out if it is just a placebo, or are there measurable effects
from taking a supplement? [music]
I must admit, I have recently topped up my levels of vitamin D and I've cheated a little bit,
I've had some winter sun and I feel brilliant.
Although, that could in part be due to the fact that I've had a few weeks off
work with it. However, before we delve into the conversation around supplementation, I want to
find out a little bit more exactly what vitamin D does to our health and our bodies as a whole.
I expect most of you are aware of vitamin D's importance when it comes to bone health. It's
actually used to help our body absorb calcium and phosphorus, which is needed
to build stronger bones. Earlier I caught up with nutritionists, Renee McGregor, who actually
started off by explaining that vitamin D plays a far bigger role in our health than I realized.
[music] First things first, Renee, what does vitamin
D actually do? Why is it so important for us? Renee McGregor: Vitamin D, I mean, obviously, for
triathletes, runners, cyclists, it's important on so many levels. Firstly,
we know that vitamin D is really important for our immune health. There's been loads
and loads of links that have shown that, for those individuals where vitamin D is below
par, it can really depress your immune system. We saw, definitely, prior to the science coming out
about vitamin D, that those athletes that had low vitamin D tended to have a much higher prevalence
of particularly respiratory tract infections in the winter months. Then by giving them vitamin D,
through the winter, and then them topping up over the summer with sunshine and
exposure to the sun, the following year, their incidence of illness went down. So,
vitamin D is really what for immune health. The other thing that a lot of people don't
realize is that it's also really important in muscular recovery. The more training you do, the
more vitamin D you're going to utilize. This is, I think, why sometimes people are really surprised
that they might be taking a low dose vitamin D, or maybe they've spent the summer outside and
they're like, "I don't understand why my levels are still so low." If you're an athlete that's
training really hard, actually, your body will be draining that source alongside quite quickly.
One of the symptoms you might notice is, if you haven't got enough vitamin D is, that
recovery between training is poor. Also, that you might notice you get a lot more muscle soreness
and sometimes you can even get myalgia, that real muscle lethargy and pain,
in severe cases that can happen. We've identified quite a lot of athletes
that we work with where they're presenting with these symptoms of severe tiredness,
they're walking through treacle, quite like pain as if there's some autoimmune thing. Actually,
when we've done their blood tests, their vitamin D levels are just really, really low.
Vitamin D is really important for that. Then obviously, the other reason why vitamin
D is so important is for your bone health, which I think most people are aware of, and probably the
only thing people are really aware of and not the other two features. It's a really, really vital
nutrient in an athlete's diet? Heather: How much do you actually need,
Renee? If you had a blood test, how much should you have? Are there any numbers?
Renee: Ideally, for athletes, or people who are physically very active, should we say,
you want that number to be above 90. That's quite rare actually. Depending on where you're at in
the scale, so if you are, say, between 50 and 90, then you probably need a dose of about a thousand
international units a day, particularly through the winter months. If you're much below 50,
then we'd be probably giving you slightly higher dose, maybe something like 4,000 international
units a day. If you're in the 20s, which I have had some athletes, they're in the 20s, then you
probably need some proper medical intervention and you need some really pretty high dose
supplements, which your doctor can give you, and should be under medical supervision.
It does depend on where you're at in that scale. Heather: A lot of our viewers, obviously aren't
going to be having regular blood tests. How would you know how much
you need if you're not having a blood test? Renee: It's really tricky but I generally say to
people, especially between the month of September and April, I would probably just have a low-level
dose; so I'd go for the thousand international units a day. It's very hard--
Although there are some people who can overdose and they can get very, very high levels,
it's very rare. In my practice and in my experience, I've only seen
two athletes with very high levels, and that was just because they were taking
really high doses and had also been in the sun and just didn't need to do it all. It's quite
hard to overdose, I'd say a basic dose would be about a thousand international units.
If you maybe notice some of the other symptoms that we were talking about earlier,
then I would encourage you to go and get a blood test somehow or even use one of
the biomarker companies that can just detect the vitamin D on its own,
then at least that way, it's not too big cost out but you have an idea of where you're at.
It's also slightly genetic to a certain degree as well, certain ethnic groups, for example, the
darker the skin you are, the more vitamin D you're going to need. Some people just don't have the
ability to absorb vitamin D very well. It's being mindful that there's there are situations where
you might be taking it, but you're still not getting enough. That's where, it would be useful
to know where your numbers are. I know personally, my numbers always run quite low, so, I basically
take vitamin D all year round because of that, but that's because I know my numbers run low.
Heather: You've touched on it there, the ability to absorb it. I know some people even
argue that you can't absorb it as a supplement. Are there anything that you can
do that can actually help you absorb it? Should you take it with a certain food or drink?
Renee: It's a fat-soluble vitamin so you should, ideally, try and take it with something that's
going to help you absorb it, so fat, things like peanut butter on toast, when you have your vitamin
D could be quite useful. We do recommend that you try and have your vitamin D in the morning and
not in the evening because it does interfere with your production of melatonin. Some people tend to
take it in the evening and then wonder why they can't sleep, so definitely, try and take it in
the morning. I actually take it first thing in the morning and usually take it first and then I eat,
which tends to be the best way to do it. Heather: If you're not a fan of supplements,
I've never been a fan of supplements, and I don't actually take vitamin D.
Obviously, in normal years, I do go away quite a lot than I've been away now. Are there some
foods that we can eat that can actually help supplement us, or is it, in your mind,
do you think everyone should take vitamin D? Renee: It's a really good question. I think
it's a difficult one. We know as a population study, majority of people, particularly in
the Northern Hemisphere, probably do need to take a vitamin D supplement through the winter months.
There's quite a lot of good data on that. Obviously, some people
who go away, maybe they're living in different parts of the world, they might not need to.
There are some foods that do give you a vitamin D but it's just quite hard to get the amounts
you need. The foods that you would be relying on would be things like an oily fish, the bony oily
fish because that's very, very high in vitamin D. Some dairy products are fortified with vitamin D,
so that can be quite useful. But there's not an awful lot of food that's going to give you
vitamin D which is the tricky bit. That's why-- I don't tend to recommend supplements in general,
but it's the one supplement that is quite tricky to get through your diet if you're not careful.
Heather: Yes, it was the one supplement that our nutritionist, as pentathletes, insisted
we had to take and it was non-negotiable, which I struggled with but had to accept. Obviously,
in the summer you're saying we don't necessarily take it and sunlight is a big factor but,
are there any kind of-- I know it's such a broad spectrum because we've got people watching in
all parts of the world or different latitudes and longitudes and different times of year,
but is there a guidance as to how much sun and what angle or time of year that you need?
Renee: Yes. What they say is that to absorb the right amount of sunlight, it should be between
the hours of eleven and three, which already makes it problematic for most office workers and people
who are working, from the months of April to September is what we say obviously in the UK.
Ideally, for about 20 minutes is a minimum and you want that without any sun cream on. You want
to be sat outside and you want exposure of it to your face and your forearms, is what they say.
It's actually quite tricky. Unless you're outside working and then you remember to put
your sun cream on, because obviously that's another aspect of it. I actually found that
even though Australia has so much more sunlight, because of the amount of sun cream that they're
always encouraged to use, their levels of Vitamin D were still very low. It's quite an interesting
one. I think it's quite tricky to get it right and I haven't yet found a formula to-- I think perhaps
the key is trying to get out in a break, like a lunch break or something, during those months,
sit outside for 20 minutes and then go back in and then put your sun cream on,
is the only thing I can recommend. Heather: It's a difficult one, isn't it? Because
then you've got the doctors who are talking about skin cancer and skin care, but the health that
you need Vitamin D. It sounds very tricky, but a great guidance there, Renee, thank you very much.
A big thanks to Renee for her time and her knowledge on that topic. It just goes to
show how important Vitamin D is. Maybe I shouldn't have been less reluctant on taking that supplement
back when I was an athlete. I know you guys live all over the world and some of you will be lucky
enough to have enough sunshine to get your requirement of Vitamin D. Just make sure you
do so carefully, please. If you're stuck in the UK like us, then it's unlikely that the few day light
hours we do have are going to give you enough, so, you might want to consider taking a supplement,
but of course that is up to you. It's just so hard to know if you're having enough because,
who feels great at this time of year? I know I don't but if you do have the resources,
then a blood test could be interesting. If you have had one in the past and you've found
some interesting results or maybe you were really struggling with training and you started taking
Vitamin D and found a notable difference in how you felt and how you could train, please do let
us know. I think it's a really interesting topic, so share your thoughts and your comments in the
comments section below. Hopefully, you've enjoyed this, you've learned something like I have,
give us a like if so. Remember, you can follow us on our social media channels and you can also
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