Vitamin D Factsheet

  • 29 Oct 2019
  • Posted by Samantha Varriale
  • Nutrients
  • Comments

Vitamin D deficiency is extremely common in the UK and has been linked to the following health issues:

  • Poor immune function - getting sick often
  • Low mood & depression
  • Fatigue & tiredness  
  • Constipation
  • Low bone mineral density
  • Hormonal imbalance
  • IBS


What is vitamin D?

Vitamin D is a fat-soluble vitamin, meaning it’s absorbed by the body through fatty tissue and then stored in these tissues or the liver

It is made in the body from cholesterol when the skin is exposed to natural sunlight (without sunscreen)

Unlike most vitamins, vitamin D functions more like a hormone: every cell in your body has a receptor that allows it to absorb the mineral


What does vitamin D do?

  • activates cells that fight infection and reduce inflammation 
  • maintains and builds bone strength by aiding the absorption of calcium from your gut and kidneys,


What foods contain vitamin D?

Vitamin D is found mainly in animal products such as:

  • Fish such as salmon, mackerel, sardines and tuna
  • Eggs
  • Milk, butter and cheese
  • Fortified foods
  • Mushrooms

If you are vegetarian or vegan, it’s likely that you’ll need to supplement to get the right level of vitamin D.


Other vitamins linked to Vitamin D

  • Magnesium assists in the activation of vitamin D in the body
  • Vitamin D stimulates the absorption of calcium, which is important for bone health


Vitamin D deficiency symptoms - who is at greatest risk?

  • Anyone who lives in the northern hemisphere - that includes the UK
  • If you spend most of your time indoors
  • Those who eat very little fish or dairy


What are the UK guidelines?

The NHS recommends that from October to March, everyone should consider supplementing with Vitamin D.  For children the advice is:

breastfed babies from birth to 1 year of age should be given a daily supplement containing 8.5 to 10 mg of vitamin D

formula-fed babies shouldn’t be given a vitamin D supplement until they’re having less than 500ml (about a pint) of infant formula a day, as infant formula is fortified with vitamin D

children aged 1 to 4 yrs old should be given a daily supplement containing 10 mg of vitamin D


The link between vitamin D and overall health:

Some studies have shown that low levels of vitamin D have been linked to a number of medical conditions including: 

  • Heart conditions
  • Autoimmune disease
  • Type 2 diabetes
  • Depression
  • Dementia and Alzheimer’s

It is not possible to say that Vitamin D deficiency causes any of the list above, but there is a scientific rationale to keeping your vitamin D levels optimised. 


If you have any questions about Vitamin D or want to book a health screen with Dr Shilpa, book an appointment at or call 0203 303 0326.