Vitamin D has been in the news a lot over the last few years, so let’s have a look at it.

After my blood tests showed I was deficient in vitamin D as well as iron, I decided I’d write a post about it at some point, particularly as it’s been suggested that it can reduce the severity of Covid 19. As it was trending on Twitter a couple of days ago and popped up several times on my Instagram feed I took that as a sign that now was the time!
So..what is vitamin D?
Vitamin D is actually a family of related substances, the most common of which are D2 and D3.
Why do you need it?
It promotes the absorption of calcium and helps regulate the levels of calcium and phosphate in the blood.
It helps to regulate bone growth and repair.
It reduces inflammation.
It modulates processes such as cell growth, neuromuscular and immune function, as well as glucose metabolism.
In short, it’s really important for our bones, teeth and muscles. A deficiency in vitamin D can lead to rickets in children and osteomalacia in adults. Sufficient vitamin D and calcium also help to protect against osteoporosis.
Where do you get it from?
Vitamin D is a fat-soluble vitamin and the D3 form occurs naturally in some foods, predominantly fatty, animal-sourced foods.
- oily fish – such as salmon, sardines, herring and mackerel
- red meat
- liver
- egg yolks
- fortified foods – such as some fat spreads and breakfast cereals
Vitamin D2 occurs in a very small number of sources, mainly in mushrooms that have been grown in UV light, yeast and some fortified foods, so it can be particularly difficult for vegans and vegetarians to get enough purely from their diet.

Should I take a supplement?
Luckily, we also produce Vitamin D ourselves when exposed to enough UV light but in the UK, in autumn and winter, we cannot make enough. NHS guidelines state that everyone should consider taking a supplement during these months.
However, there are some groups of people who should take a supplement all year round, including –
- people who get outdoors much – e.g, anyone housebound or frail.
- anyone in an an institution such as a care home.
- anyone who covers most/all of their skin when they’re outside.
Additionally, anyone with dark skin may not make enough Vitamin D and should consider a supplement too.
So, there you go. That’s pretty much everything you need to know and, as it’s pretty grey and windy in most of the UK at the moment, you might want to keep taking your Vitamin D tablets for at least another month or two!