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How are your vitamin D levels?

You may think spending time in the sun in summer and supplementing in winter may be enough to give you optimum vitamin D levels. But this may not be the case!

Vitamin D is a fat-soluble vitamin also known as the 'sunshine vitamin' because we produce most of what we need by the action of sunlight on our skin. Although some foods contain small amounts of Vitamin D, relying on eating oily fish or fortified fats isn't enough to get Vitamin D to optimum levels. Vitamin D aids the absorption of calcium and phosphate in the body and is vital for keeping bones and teeth healthy. 


A little Medichecks experiment 

Here at Medichecks HQ during the beautifully hot summer we experienced this year, our Marketing Manager Bella and I decided we would embark on a little experiment to see how the sunny weather would affect our vitamin D levels.

In December of last year, my Vitamin D levels were at an incredibly low 15.5 nmol/L - classed as a deficient result. During the winter months this year I spent 12 weeks travelling around Australia where average temperatures were around 30 degrees Celsius every day. 

When I returned home in June, I decided to retest my vitamin D to see how this time in the sunshine had affected my levels. My result came back as 55.6 nmol/L which was certainly an improvement on December, but was still surprisingly on the lower side of the normal range. Bella, on the other hand, had spent the winter here in the UK and her vitamin D in May was 45.6 nmol/L, a result classed as insufficient. 

During the summer I did not go abroad again but got plenty of sunshine here in the UK during the scorcher of a summer we had. Bella took every opportunity to top up her tan, by travelling abroad several times and attending a few festivals here in the UK. We both tested our levels again in August - mine had only risen slightly to 60 nmol/L whereas Bella’s had increased greatly to 124 nmol/L, a healthy vitamin D level. 

As the warm weather here in the UK disappeared and the cold weather crept in, neither of us were outside anywhere near as much as we were in the summer and we decided to test our levels once again. In October my result had fallen slightly to 58 nmol/L and in November Bella’s level was at 77 nmol/L. Both of these results lie at the lower end of the normal range and had dropped since our earlier testing in August. I had expected my October result to be much lower than my previous result, but I have over the last few months been incorporating more oily fish into my diet so this could have had an impact on my levels.  

We recognise that this was not a properly conducted trial but the results are informative nonetheless! Neither of us have supplemented so far and our vitamin D levels have started to drop - even with a summer full of sunshine, our levels were still on the lower end of the normal range. To avoid our vitamin D levels becoming insufficient or even deficient, we will both be supplementing vitamin D over the winter months to keep our levels topped up and will retest in the new year to see what effect this is having.

Bella's results

Emily's results

How are your levels?

Can’t we just assume that if we spend enough time out of doors and possibly top-up with a supplement in winter that we will have optimum levels? Well no, we can’t because unless you know your starting point it is difficult to know what level of supplementation you need if any.

Many people in the UK do not produce enough Vitamin D, especially in the winter months with fewer daylight hours. Vitamin D deficiency is very common, especially in the winter months when sun exposure is reduced. 

Our advice for optimum Vitamin D is to take the guesswork out and start with a Medichecks Vitamin D Blood Test. If you haven't been supplementing then it could provide the incentive you need to start, and if you are supplementing then it will tell you whether you are getting enough. Then we advise you to retest after a few weeks to see whether the supplement you are taking is strong enough or whether you need to adjust the dose