Everything You Need to Know About Vitamin D

Dr Hilary Jones
By Dr Hilary Jones

Dr Hilary qualified in 1976 at The Royal Free Hospital in London having studied art subjects at A-Level then converting to a six year medical degree.

Vitamin D Deficiency has reached endemic proportions in many parts of the world.

It is estimated that about 60% of Brits are Vitamin D deficient.

A new Government-commissioned report by Public Health England has advised that all Britons take a minimum of 10 micrograms (400IU) of Vitamin D supplements daily to prevent Vitamin D deficiency and to protect bone and muscle health.

We need Vitamin D to help the body absorb calcium and phosphate from our diet which helps keep bones, teeth and muscles strong.

Over the last two decades, we have had strong and robust evidence to show that Vitamin D is important for almost every single aspect of health.

Vitamin D used to be considered a nutrient essential for bone health and it was conventionally thought that if you had enough Vitamin D you wouldn’t get rickets and osteomalacia.

Now a spectacular collection of evidence shows that Vitamin D is essential for protecting against everything from heart disease and cancer to inflammatory disorders, Multiple Sclerosis and much more.

Vitamin D is known as the Sunshine Vitamin. We need to make vitamin D every day and we do this with the help of sunshine.

But in the UK we don’t get enough sunshine in the Autumn and Winter months due to our Northerly Latitude leaving up to 60% of people deficient.

What is Vitamin D?

How can you get Vitamin D?

Most people get about 90% of their Vitamin D from sunshine and 10% from their diet.

We can make Vitamin D through regular sun exposure for 10-15 minutes a few times a week in the summer months in the UK.

In the winter months, we cannot make enough Vitamin D through sun exposure as the UV Index isn’t high enough.

Your body can’t make Vitamin D when you are sitting indoors in the sun because UVB doesn’t pass through glass and it's UVB that helps our bodies make Vitamin D.

If you cannot make enough Vitamin D from sunshine then some foods are a good source of vitamin D.

These include oily fish like salmon, mackerel, herrings and sardines and some red meats and eggs.

The problem is many of us don’t eat salmon and eggs every day in sufficient amounts.

Another problem is that Vitamin D is only stored in the body for 1-2 months so by mid-winter most people are deficient as stores have been depleted.

How effective are vitamin supplement's


Experts agree that if you can’t get enough Vitamin D through sun exposure or your diet then supplements are a good idea.

Many experts believe that Vitamin D should be consumed in far high doses than is currently recommended because of its powerful cardio-protective and anti-inflammatory effects.

If you are following Public Health England’s advice on Vitamin D supplementation levels at 400IU per day or 10mcg then you will be missing out on many of the great health benefits of Vitamin D.

I always advise1000 – 2000IU of D3 for anyone concerned they are not getting enough from the sun and dietary sources.

Take Vitamin D in its D3 form in your supplements as it's more effective and bioavailable than the D2 form and is more constant in the bloodstream.

Research has shown that D3 is about 80% more potent and produces 2-3 times more storage than the D2 form.

At-Risk Groups:

  • Anyone over 55 (less efficient at making it)
  • Anyone with darker skin e.g.Asian, Mediterranean, Afro-Caribbean
  • Anyone who covers up in the sun or who wears sunscreen
  • Teenagers who don’t get out much
  • Those on restricted diets – vegan, vegetarian, no fish
  • Post weight loss surgery, gastric bands
  • Housebound people
  • Infants and children

Practical Tips:

  1. Allow sunshine onto your lower arms or legs (without sunscreen) from late March to late September 11-2pm when UVB is at its highest. After 15-20 minutes most people will have achieved the exposure they need so apply sunscreen to protect the skin.
  2. If you have darker skin you will need to spend longer in the sun unprotected to make the same amount of Vitamin D as someone with lighter skin.
  3. In the UK the winter sun doesn’t generally contain enough UVB for us to make vitamin D so you need to take it in your diet or as a supplement.
  4. Children under 5 should supplement their Vitamin D – See Your Gp.
  5. Anyone with dark skin (Mediterranean, Asian, Afro-Caribbean) who doesn’t get much sun exposure should take Vitamin D supplements all year round.

Your Doctor can perform a blood test to check your Vitamin D levels. Ask for a test of 25 Hydroxy Vitamin D test as this is the most accurate blood test.

Ideally, you want your levels to be between 50-70ng/ml or 70-100ng/ml if you have heart disease.

I strongly recommend that each and every one of you request a Vitamin D blood test check with your Gp.

Vitamin D supplementation is one of the simplest and most profound measures you can take to improve your overall health and wellbeing.

How can your doctor help with vitamin supplement's

Many thanks to the author of this blog Dr Hilary Jones who is a GP, TV Presenter, Medical Broadcaster, Author and Public Speaker.

Dr Hilary qualified in 1976 at The Royal Free Hospital in London having studied art subjects at A-Level then converting to a six-year medical degree.

In 1979 he worked for a year as the single-handed medical officer on Tristan da Cunha, the most isolated inhabited island in the world.

In 1981 he worked as a troubleshooting GP and Emergency Doctor for the oil industry at Sullom Voe in Shetland for Offshore Medical Support.

Thanks to the author

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