Are you getting enough of vitamin D, the sunshine vitamin?

Sunlight is the major source of vitamin D, putting most of us at a high risk of deficiency because of our weather
Sunlight is the major source of vitamin D, putting most of us at a high risk of deficiency because of our weather

As you read this, we are feeling the aftermath of Storm Agnes, on top of having already experienced a number of dark and gloomy autumn days.

At this time of year, with the seasons changing, we all need a reminder that most of us could do with a little top up of the sunshine vitamin, vitamin D, especially as it has been severely lacking in recent months.

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Vitamin D is produced in the skin when we are exposed to sun. It is a fat-soluble vitamin that is essential for supporting bone health and a healthy immune system.

The major source of vitamin D is sunlight, which puts most of us at a high risk of deficiency, considering where we live and how few sunny days we had this summer.


Vitamin D has lots of important functions in the body. It is essential for bone health, helps to regulate our immune systems and is required for cardiovascular heath, brain function and muscle health.

It helps calcium absorption, so any function in the body that requires calcium needs vitamin D in sufficient supply too.

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In recent years various studies have suggested a link between low vitamin D levels and Covid-19 symptoms. We know that vitamin D has proven to have some effect protecting against other respiratory tract infections like colds and flus, so it could be an important part of your nutritional immune support coming into the autumn and winter.

Many people with autoimmune conditions like MS, rheumatoid arthritis and lupus take a vitamin D supplement regularly, as research shows that a vitamin D deficiency can be a risk factor in the development of these conditions.

As well as supporting our physical health, vitamin D is also important for our mental wellbeing. A deficiency can lead to low mood and depression, and may be a factor in SAD, seasonal affective disorder.


Although the main source of vitamin D is through sunshine on our skin, it is found in small amounts in food too. The best dietary sources are:

  • Fortified foods
  • Oily fish like trout, salmon, mackerel and tuna and cod liver oil
  • Liver
  • Egg yolk
  • Mushrooms – leave them on the windowsill as their vitamin D levels will increase if they are exposed to light
It is recommended that we take a vitamin D supplement between October and May
It is recommended that we take a vitamin D supplement between October and May


As vitamin D comes from food, sunshine and nutritional supplements, the best way to know if you are getting enough is to have your levels checked.

You can buy a simple pinprick blood test that you can do at home. Pick one up over the counter from chemists or online. Most of the tests will give you an indication of how much you should supplement to increase your levels if you need to too.

Some people are at a higher risk of developing a vitamin D deficiency than others.

The main risk factors for vitamin D deficiency are:

  • Lack of daylight exposure/staying indoors
  • Having darker skin
  • Being older
  • Family history/genetics
  • Being overweight
  • Using sunscreen

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It is recommended that we take a vitamin D supplement between the months of October and May and for most adults, 2,000iu is the recommended level.

Most supplements provide somewhere between 400iu (the minimum requirement to prevent deficiency) and 2,000iu (the suggested optimum level).

Just make sure your vitamin D is in the D3 form and not D2; most of the supplements are in the D3 forms these days.

Ideally, take vitamin D3 alongside vitamin K2 to help improve calcium absorption and make sure the calcium gets to where it is needed.

Dietary sources of vitamin K2 include sauerkraut, dark chicken meat, pork and full fat dairy, or as a supplement along with vitamin D.


Yes –and in the case of vitamin D, more is not better.

Vitamin D toxicity is rare, but symptoms include nausea, vomiting, weakness, dehydration, constipation, muscle weakness, bone pain and kidney stones.

And if all else fails, book yourself a holiday and jet off to sunnier climes...